Patent Application
20140255984
The invention generally relates to the inference of threats from the collation of results of detected micro-organisms across an extended area, to the culture and analysis of micro-organisms in order to determine the threat, both in the laboratory and in the field, and the collation of results from multiple instances of analysis to allow the drawing of the inference.
More particularly the invention relates to the detection and enumeration of multiple differing micro-organisms from changes in the colour of a culture medium in which the organisms are immersed, the tracking of populations of these microbiological organisms in certain locations and tracking of the occurrence and spread or decline of spatial populations of microbiological organisms.
Additionally the invention relates to the standardisation of a growth medium and adjuvants for micro-organisms in an analyte, and the medium to render such an analyte biologically inert after analysis.
More particularly the invention relates to the provision of a portable relocatable device for culturing micro-organisms, analysing the results and reporting these to a remote point for collation of data.
Dye reduction tests are known but are not considered to be reliable indicators of the type of microorganism or the quantity present. They provide a rough guide to indicate the presence or absence of bacteria.
The following is an extract from Atherton, H. V. and Newlander, J. A. 1977 Chemistry and Testing of Dairy Products. 4th Edn. AVI, Westport, Conn. cited at http://www.foodsci.uoguelph.ca/dairyedu/resazurin.html
“The methylene blue reduction test is based on the fact that the colour imparted to milk by the addition of a dye such as methylene blue will disappear more or less quickly. The removal of the oxygen from milk and the formation of reducing substances during bacterial metabolism causes the colour to disappear. The agencies responsible for the oxygen consumption are the bacteria. Though certain species of bacteria have considerably more influence than others, it is generally assumed that the greater the number of bacteria in milk, the quicker will the oxygen be consumed, and in turn the sooner will the colour disappear. Thus, the time of reduction is taken as a measure of the number of organisms in milk although actually it is likely that it is more truly a measure of the total metabolic reactions proceeding at the cell surface of the bacteria.
The resazurin test is conducted similar to the methylene blue reduction test with the judgment of quality based either on the colour produced after a stated period of incubation or on the time required to reduce the dye to a given end-point. The resazurin test may be a valuable time saving tool if properly conducted and intelligently interpreted, but should be supplemented by microscopic examination.
Results on the reliability of the resazurin tests are conflicting. One study in comparing the resazurin test with the Breed microscopic method on 235 samples found the test reliable. Other reports state that the resazurin test is an unreliable index of bacteriological quality in milk. A major criticism of the method is that the resazurin reduction time of refrigerated bottled milk at either 20° or 37° C. is much too long to be of any value in evaluating bacteriological spoilage of stored milk.
Standard Methods notes that under no circumstances should results of either methylene blue or resazurin tests be reported in terms of bacterial numbers. The two dye reduction procedures are described in more detail in Chapter 15 of the Thirteenth Edition of Standard Methods compiled by the American Public Health Association.”
There have been many attempts to develop tests to identify the bacterial species or to determine the extent of contamination. Most such tests require samples to be couriered quickly (preferably in a chilled state) to a laboratory, where the samples are cultured for 24 to 48 hours (typically on agar plates) and the resulting cultures examined by microscope to determine the amount and type of bacteria present. Typical turn around times for such tests is 3 to 5 days, which is far too long to provide adequate warning of contamination in waterways or on beaches. Resulting in the closure of beaches long after the contamination has passed. The time delays in completing and reporting such tests for foodstuffs especially for shellfish, means that either the batches have to be recalled after dispatch or held in store for 5 days until clear test results have been received. Similarly lengthy bacteriological testing of poultry and of dairy products, among others, has enormous economic consequences. There is clearly a need for a far more rapid yet accurate testing system for the presence and type of bacteria so that any contamination can be dealt with promptly and the source of the contamination can be determined so that remedial action can be taken. This is especially so in food processing plants, but applies also to marine farms.
It is known to measure the occurrence of microbiological organisms such as coliform bacteria in the environment by taking samples of organisms, culturing the samples in a suitable medium and measuring the number of organisms in the medium after culturing. It is also known to repeatedly sample particular locations, for instance swimming beaches, to provide an indication of the continuing state of the current population of an organism of interest. In this way the level may be monitored on a more or less continuous basis.
It is known to provide portable analysis devices for analysis of chemical substances, such as gases in the air, trace contaminants in water and metal particles in oil. Such devices are generally distinguished by low power requirements allowing the use of small batteries.
Unfortunately current methods for the culture of micro-organisms requires that the culture be kept at a constant temperature for a period of at least 24 hours. Maintaining a culture at a constant temperature for such a long period in a location where the device has no mains power supply is highly dependent on the ambient temperature, in that if the ambient temperature varies much from the required culture temperature the device will require an impractical battery size to give the required endurance. Additionally some method of accurately detecting the micro-organism count is required.
Ever since the creation of instruments able to test a sample for the presence of an analyte of interest, a need for containers for aiding in the collection and testing of the samples has existed. Accordingly, sample containers have been made that permit a user to take a sample, bring the sample to the lab, and then either transfer the sample to another container for testing, or use the container directly in the testing process. Although these previously developed containers are adequate, the containers are not without their problems. Moreover, it has been found that existing containers often require excess handling by human hands, often requiring the opening and closing of the container multiple times during sampling and testing, which often leads to the introduction of contaminates into the sample, and needlessly exposes the users to potentially harmful substances and micro-organisms. Also, once the testing has been done, often the testing container and its contents must be properly disposed of as hazardous waste as the contents may still contain substances or micro-organisms that may be harmful to humans or the environment.
Examples of prior art tests can be found in the following documents:
The Applicant has described a novel test machine and method based on machine detectable changes in the colour and transmissivity in a growth medium as a function of the number of micro-organisms initially present in the sample, as described in the applicants NZ patent 539210. Typically the growth medium is a liquid which contains a micro-organism growth promoting adjuvant and an indicator such as resazurin which is reduced by the action of the micro-organisms, thereby changing the colour of the growth medium. The colour changes are due to changes in the indicator, changes in other chemical molecules in the liquid, and changes in the reflection of light from particles, such as organisms or organism clumps, in the liquid. Turbidity may be one of the factors affecting the overall transmission of light through the medium.
While it is possible to measure the growth of organisms optically as in the above patent application it is not possible to differentiate between organisms if there is more than one organism in the sample. The growth curves for populations of two or more organisms form one result and observation does not give any indication of which organism predominates or is most important from the user's viewpoint.
In such circumstances it is normally necessary to resort to growth and inspection on agar plates in order to differentiate the micro-organisms.
Therefore a need exists for a solution to the problem of tracking populations of micro-organisms in one or more locations and predicting from the measurements the past and future populations of the micro-organisms.
There still remains the problem of tracking the occurrence of a micro-organism over an extended area, detecting the progression of the population both in terms of area and level of occurrence, and predicting the future population.
Further, if a population or incipient population is to be monitored over an extended physical area, the human effort required to do this is high, involving repeated measurement in many places.
It would be desirable to provide a portable device for in-situ analysis of micro-organisms and remote reporting to allow simple detection of biological contamination at remote sites, or the spread of organisms, as for instance in a “red tide”. It would then be possible to provide unskilled staff with the devices to carry into the field to be placed at a desired location, supplied with a sample to culture, and left to report the results of the culturing to a central point. This would allow the rapid delineation of a microbial threat and the relatively simple tracking of the area of its expansion or contraction.
This rapid deployment and return of results allows the creation of a method of providing a response to biological contamination in many foodstuff supply situations.
A number of such applications are listed below. All of these are industries or services which can occur within a physical catchment or series of catchments.
Each industry or service can be viewed in the same way by identifying each stage of the supply or production of a foodstuff at which biological contamination could take place and providing for testing at these stages. For instance with a dairy farm, the milking process, the transportation, the processing, the distribution and supply chain all provide opportunities for contamination. Just as the water in a large physical catchment flows through the landscape possibly degrading on its journey, so too does the milk from the farm to the consumer face similar biological challenges.
In each case a catchment for a food product is inter-related and affected by human intervention. In each of the supply services below a possible point of contamination is identified. At each of these points a contamination test could be made.
Accordingly, there exists a need for an improved testing container that has one or more of the following characteristics: reduces the potential of contaminates being introduced into the container during sampling or testing, reduces the potential that the contents of the container will cause harm to humans or the environment during or after sampling or testing is complete, is more reliable, is less expensive to manufacture, has less parts, is easier to use, and is more reliable.
The present invention provides a solution to this and other problems which offers advantages over the prior art or which will at least provide the public with a useful choice.
It is acknowledged that the term ‘comprise’ may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term ‘comprise’ shall have an inclusive meaning—i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term ‘comprised’ or ‘comprising’ is used in relation to one or more steps in a method or process.
Within the specification reference is made to colour “frequencies” and colour “bands”. The reference to “frequency” is to the general frequency of light of a particular colour and to “band” as light extending over a range of frequencies but of one general colour.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein; this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
It is an object of the invention to provide a testing method for aiding a user in the collection and testing of an environmental sample that ameliorates some of the disadvantages and limitations of the known art or at least provides the public with a useful choice.
It is a further object of the invention to provide a method of automatically carrying out tests of environmental samples and reporting them back with the possibility of collating continuing results to produce an indication of any threat from the environment.
It is a further object of the present invention to provide a solution to this and other problems which offers advantages over the prior art or which will at least provide the public with a useful choice.
In a first aspect the invention provides a portable micro-organism detection apparatus comprising:
Preferably the incubator has a transmitter to send the results to a base station.
In another aspect the invention provides a method of detecting micro-organisms from changes in the colour of a growth medium in which a sample potentially containing micro-organisms is immersed, by sealing a sample from a location in a rigid substantially transparent fluid container with at least one light path through the container, placing the container in an incubator, transmitting light into the fluid container over time from at least one light source mounted on or in an incubator; detecting light of at least one colour which has passed through at least part of the fluid from the at least one light source by at least one light sensor mounted on or in the incubator, sending data from the at least one light sensor to a micro-processor having a comparator which analyses the light changes over time resulting from a sample in the rigid substantially transparent fluid container being incubated in the incubator, by comparing the detected light changes with stored calibration information to determine the presence or absence of at least one particular micro-organism; and stores the results of the comparison for the sample in a data logger together with location information and a date and time stamp for that sample.
Preferably the results are transmitted to a base station and stored in a database.
Preferably a plurality of samples is analyzed and the results transmitted to the base station for analysis by a computer.
Preferably rate of growth over time of the micro-organism(s) within the sample is assessed to enumerate the number of micro-organism(s) detected at the location.
Preferably the computer analyses the occurrence or spread or decline of spatial populations of microbiological organisms from the sample data and location and date time stamp of each sample.
Preferably the rate of growth over time is matched against stored calibration information for differing micro-organisms to determine the closest match.
Preferably the growth medium is optimised for E. coli.
Preferably the growth medium contains lactose, Casitone, NaCl, KCl, CaCl2, and MgCl2 as growth adjuvants.
In a further aspect the invention provides a method of detecting micro-organisms from changes in the colour of a standardised growth medium containing one or more indicator dyes in which a sample potentially containing micro-organisms is immersed, by sealing a sample from a location in a rigid substantially transparent fluid container with at least one light path through the container, placing the container in an incubator, transmitting light into the fluid container over time from at least one light source mounted on or in an incubator; detecting light of at least one colour which has passed through at least part of the fluid from the at least one light source by at least one light sensor mounted on or in the incubator: sending data from the at least one light sensor to a micro-processor having a comparator which analyses the light changes over time resulting from a sample in the rigid substantially transparent fluid container being incubated in the incubator, by comparing the detected light changes with stored calibration information of different micro-organisms which have been calibrated by incubating known micro-organisms in the same type of container with the same amount and type of growth medium and same type of indicator dyes to determine the closest match or matches and report the presence or absence of the different micro-organisms.
Preferably the results of the analysis of the sample are stored in a data logger together with location information and a date and time stamp for that sample.
Preferably the results are transmitted to a base station and stored in a database.
Preferably a plurality of samples is analyzed and the results transmitted to the base station for analysis by a computer.
Preferably rate of growth over time of the micro-organism(s) within the sample is assessed to enumerate the number of micro-organism(s) detected at the location.
Preferably the computer analyses the occurrence or spread or decline of spatial populations of microbiological organisms from the sample data and location and date time stamp of each sample.
Preferably the growth medium contains lactose and growth adjuvants.
In a yet further aspect the invention provides a method of detecting and enumerating micro-organisms from changes in the colour of a growth medium in which a sample potentially containing micro-organisms is immersed, the recording of the enumeration of these micro-organisms in known locations from this enumeration the tracking of the occurrence and spread or decline of spatial populations of microbiological organisms characterised in that the growth medium is initially sealed within a container in which the sample is deposited, that the growth medium is released into the sample, that at least the transparency of the growth medium is monitored optically with time and that an enumeration of at least one micro-organism dependent on the elapsed rate of growth of the organisms within the sample is reported for recording at a remote location.
Preferably the transparency is monitored over at least one colour band.
Preferably the transparency is monitored separately over several colour bands.
Preferably the turbidity is monitored in addition to the transparency.
Preferably the elapsed rate of growth is matched against that for differing micro-organisms to determine the closest match.
Preferably a comparison is made by normalizing a record of transparency of a sample with time and comparing the normalized record with those of known micro-organisms in the same growth medium under the same physical conditions.
Preferably the elapsed rate of growth is matched against multiple micro-organisms within the one sample if no match is found against any one of the micro-organisms.
Preferably the growth medium sealed in the container is optimised for a particular micro-organism.
Preferably the growth medium is optimised for E. coli.
Preferably the growth medium contains lactose, Casitone, NaCl, KCl, CaCl2, and MgCl2 as growth adjuvants.
Preferably Casitone is present at a concentration of between 0.1% and 1% by volume.
Preferably lactose is present at between 0.5% and 10% by volume.
Preferably the growth medium contains bile salts as an inhibitor of other non-specific micro-organisms.
Preferably the growth medium contains a redox dye indicator.
In another aspect the invention relates to a micro-organism enumerator including:
Preferably the container also includes a sealed biocide, releasable into the sample and growth medium.
Preferably the release is manually accomplished.
Preferably the sample transparency is measured by light passing through the container.
Preferably the light is originated in the incubator and detected by optical sensors in the incubator.
Preferably the sample transparency is measured and compared for a single colour of light.
Preferably the sample transparency is measured and compared for multiple colours of light.
Preferably the sample turbidity is additionally measured and compared.
Preferably the container may contain a growth medium for selectively growing a single micro-organism genus or species.
Preferably the container may contain a growth medium for selectively inhibiting the growth of one or more micro-organism genera or species.
Preferably the container growth medium is standard among all containers targeting a specific micro-organism.
Preferably the incubator reporter may contain a radio transmitter reporting the probable match.
Preferably the incubator radio transmitter is a cell phone.
Preferably the incubator is portable and self-contained as regards power for at least one sample growth cycle.
Preferably the container is transparent in at least those areas adjacent and opposed to the optical sources of the incubator.
Preferably the container is additionally transparent in those areas laterally perpendicular to the optical sources of the incubator.
Preferably the incubator includes a GPS receiver allowing self-identification of the location of the unit.
In the specification we have made reference to “location detection system” or “location detection means”. The most practical way of achieving this at the present time is to use a GPS chip (a chip set that accesses the global positioning satellite system in order to provide coordinates of the location based on triangulation from the satellites). This may be an off the shelf GPS receiver which is connected to the microprocessor, or it may be a chip set which forms part of the microprocessor.
Alternatively, other location detection systems may be used. For example the portable incubator could include a display screen, and a set of stored maps, and it may allow the operator to enter the location manually on the map stored in the incubator, or the incubator may include the coordinates of particular sample sites, which have been predetermined, and which have been identified on the map, or identified in some other way, so that the operator can then take the sample from that particular predefined location, and identify it by suitable reference to the sample number of sample location.
Preferably the incubator allows input of a desired geographically referenced location.
Preferably such a geographically referenced location may be remotely input.
In a further exemplification the invention relates to a method of cumulating and displaying the results of analysis for specific micro-organisms within a physical area by providing within that area multiple micro-organism analysis units, culturing samples from a known location within the physical area in a micro-organism analysis unit, providing remote from the physical area a central location capable of receiving results from analysis units, receiving at the central location from remote analysis units the results of analyses and the location of the analysis sample, displaying the results on a micro-organism count versus time basis on a map of the physical area, identifying from a time/count reversion a sub-area of the area as the tentative origin of the increase in micro-organisms, relocating at least analysis units to locations within the identified sub-area and repeating the method until the tentative origin is confirmed.
Preferably the remote analysis units are units as referred to above.
Preferably the step of identifying a sub-area includes as inputs the physical factors affecting transfer and propagation of the specific micro-organism.
Preferably the identification of a tentative origin may include the step of providing to the remote analysis units a new location of selected remote analysis unit.
Preferably each remote analysis unit includes a GPS location identifying unit and an audio and visual output identifying the route to the new location.
Preferably the results received from the analysis units include the time of sample collection.
Preferably multiple samples are collected from the same location over time and the method includes comparing information from the same location at different times to measure the change in occurrence at a specific location with time.
Preferably the comparison reveals the bacterial occurrence at locations within a specified area over time.
Preferably the growth trend is depicted on a map in both space and time.
Preferably the growth trend includes an output of a predicted population.
In another aspect the invention provides a method of tracking bacterial occurrence by:
Preferably each unit includes a GPS component capable of storing the GPS co-ordinates at the time of the sample collection.
Preferably each unit is set to store an identification of the person taking the sample.
Preferably each unit uses a standardised population growth test where the samples are each grown in a standardised nutrient solution in a defined sample container in each unit (where the unit acts as an incubator and an a light recording device to detect and compare changes in light transmission and reflection within the sample under test with reference samples for known populations the data of which is stored in each unit.
Preferably the information is transferred by radio transfer of a data stream.
In a further exemplification the invention consists in a portable analysis device capable of receiving an at least partially transparent culture container containing a culture medium and including: a culture medium temperature control capable of maintaining the culture medium at a specified temperature; an optical transmissivity measuring means capable of measuring the optical transmissivity of the culture container and medium and detecting changes in the transmissivity indicative of the growth of at least one micro-organism in the culture; a data logger storing data representative of the detected changes; a transmitter transmitting the logger data to a remote location; and a power source capable of powering the device to a either a desired culture end point where a significant level of a micro-organism to be detected is present or for a time beyond that required to reach that level where the micro-organism is not present.
Preferably the portable analysis device includes a location detecting system.
Preferably the location detecting system is a Global Positioning System receiver.
Preferably the transmitter transmitting logger data is a GPRS, CDMA or other cellphone protocol transmission.
Preferably the optical transmissivity is measured over at least two pathways through the medium.
Preferably the reflectivity of the medium is also measured.
Preferably the portable analysis device has a disengageable battery pack.
Preferably the culture container is contained within the device in an insulated surround.
Preferably the culture container may be heated or cooled within the surround.
In an alternative embodiment the invention consists in a method of culturing micro-organisms in a portable analysis device comprising placing into an at least partially transparent culture container a sample, a culture medium and an indicator of micro-organism growth, placing the container into a portable device capable of maintaining the container at a substantially constant temperature, measuring the optical transmissivity of the medium at at least one optical wavelength, from changes in transmissivity detecting the presence or absence of a micro-organism desired to be detected, storing information on the presence or absence of the micro-organism, reporting to a remote point the stored information and powering the portable analysis device from an internal power source capable of powering the device to a micro-organism detection end point.
The illustrated embodiment of the present invention relates generally to a sample testing container used in aiding a user in the collection and/or testing of a sample.
Referring now to
The units may be recharged and read on a regular basis, for instance weekly, and can thus provide a measure of micro-organism numbers over time.
Readings will fluctuate with time, temperature, etc. but a persistent source of the target micro-organism could, for instance, be seen to be originating from site 112.
Readings from the analysis units are entered into a database, typically at a remote central location, and may be then correlated with environmental factors to allow determination of the source of a target micro-organism and prediction of it continued expansion or contraction. Thus in the example shown the current down the streams should be known as a function of previous, current and expected precipitation, the tidal flow in and out of the estuarine lake is known, the current along the coast is known, and the daily wind vectors are tracked, the historically expected wind vectors are known, the daily temperature is tracked, the historically expected temperatures are known, the forecast temperatures, wind and precipitation are known. An initial plotting at chosen locations provide only tentative identification of the source of the micro-organism and to identify the precise source of a particular micro-organism reversion predictions based on the data received may be used to indicate sub-areas within the main area to which analysis units should be moved for better resolution of the source.
Normally such mapping is a slow process since obtaining sample culture results typically takes some 14 hours. Using the apparatus of New Zealand patent 539210 results may be obtained within 2 hours, drastically reducing the time taken to map the advance of a micro-organism and allowing one sample to be cultured while the apparatus culturing the sample is moved to the location at which the next sample is to be taken.
To make the best use of this rapid analysis each unit has an inbuilt GPS unit. This has two advantages. Firstly the precise geographical reference of the location of each unit can be automatically advised to the remote central location, and secondly each unit can be remotely programmed from the central location with its next preferred location. A relocation function allows the display screen to run a typical GPS route direction visual display with audio accompaniment to allow the remote unit bearer to be directed to the next location.
Referring now to
Lid 404 may be lowered into place and secured by rotation to form a weather tight seal with the top of the incubation compartment which will contain a standardised transparent container with a standardised analyte containing a sample from the environment. A cover (not shown) may be placed over the lid to provide additional weather protection.
On the base plate 412 of the module are a connector 409 for supplying power and output connections to the incubation module and a locating and locking projection 410 with a release washer 411 which mates with the power and communication module.
The side view of
The LED light sources may operate on different optical wavelengths, for instance white, red, green, yellow and infrared wavelengths. Each sensor may be filtered to respond only to a restricted waveband.
A ribbon cable 1002 interconnects the circuit boards including that carrying the touch sensitive keyboard and LCD display 102.
While the present example shows heaters it is equally possible to also provide Peltier effect cooling devices where the ambient temperature is expected to exceed the required incubation temperature.
The GPS does not need to be on all the time and would normally be switched on only at the start and end of the analysis to provide an initial location and a confirming location for the final report, however it may be turned on at regular intervals so that any change in the desired location for the module can be remotely downloaded from a central location and used to prompt a transfer in the location of the incubation module.
The results of the location report are taken at 1205 and stored at 1206, normally using flash RAM (random access memory) to retain the data. At step 1205 also the illuminating LED's are switched on and a reading taken of the transmissivity or transparency and reflectivity of the sample at the requisite wavelengths. At 1207 it is determined whether the sample has reached an end point and identified the level of micro-organism presence in the original sample. If so the final result is stored at 1208, reported at 1211 via the remote communication from module 1203 and then the whole device is closed down at 1212.
If no end point is detected a check is made at 1209 to determine whether the longest possible time within which a result could be expected has expired and if so a nil result is stored at 1210, and again a final report and close down takes place.
After these checks the temperature in the sample chamber is checked and if at 1213 it is found to be too low the heaters 601, 602 are switched on at 1216. Similarly if the temperature is found at 1214 to be too high the heater is turned off at 1215, and then the measurement cycle repeats, typically at intervals of approximately one minute to conserve power.
In use a sample is placed in a transparent sample container and a culture medium containing a micro-organism sensitive indication component is added to the sample and agitated. Typically the indication component changes colour when the culture medium reaches a sufficient level of concentration of the target micro-organism. Such a component is resazurin, but others are well known.
The sample is then placed in an incubation and power/communication module assembly and the keyboard and LCD display are used to choose the required time/temperature program, which is specific to the micro-organism to be detected. The keyboard is then used to start the analysis, at which point the unit can be abandoned if necessary. It is programmed to report via the radio or cell phone link, giving its location as retrieved by the GPS, and its current settings. This information may be automatically entered into a remote database to allow future verification of the unit.
Data from the on-going development or otherwise of the micro-organism within the culture medium in terms of transparency, optical transmissivity or turbidity as an indicator of an elapsed rate of growth is logged to the incorporated data logger and eventually one of two things will happen. Either there will be no appreciable change in the growth medium indicator, indicating that the micro-organism is not present in the sample, or there will be a change in colour, transmissivity or reflectivity of the sample which can be interpreted as a measure of the existence of one or more micro-organisms. When the changes reach a desired end point the analysis unit informs the communications module which will send the logger data and an indication that it is closing down to sleep mode. In this latter state a cell phone call to the embedded cell phone number will allow the unit to be rewoken and remotely controlled if required.
Because the optical waveband sensing method gives results earlier than any other known method of determining the presence of specific types of micro-organisms it is feasible to provide a battery powered device remote from any power source which is usable by comparatively unskilled personnel, since all that is required is that a sample be properly loaded into the device, and the device be properly initialised.
While the version shown is not water resistant it is possible, for instance, to provide a freely floating version with batteries recharged by solar cells which will automatically suck a portion of the medium in which it is floating into a culture medium, incubate it to term and then provide results on its position at the time the culture was loaded so that a continuing record of micro-organism of interest is provided at current or tide driven locations. For continuing results each completed sample and culture run may be ended by dosing the culture medium with a biocide, flushing the medium from the culture chamber, cleaning the chamber with a flush of water and then placing more culture medium in the chamber and loading a sample.
While the version of the device shown is comparatively large because it is intended for a sample container which is easily handled manually it is feasible to miniaturise the sample, sample holder and incubation device, for instance by using nano-etching capabilities. This in turn results in a reduction in the size of the batteries required because less volume must be heated or cooled, resulting in a considerable reduction in size of the total device.
The figure shows superimposed growth curves for organisms such as E. coli, strains 0111, 0117, 2091, 2250 and for other micro-organisms such as En. sakarazakii and for control curves such as the medium without added micro-organisms as “WC media”. It should be noted that while many of these do not detectably react either at all or much in the particular growth medium or adjuvant used in the plot shown or with the particular frequency of light used, others provide very specific growth curves.
In
E. coli produces a rapid change in the medium colour from a time which is dependent on the initial count of organisms in the medium, but which in the example shown is approximately 4 hours onwards. The media then slowly clears until it stabilises after the 14 hour mark. The various E. coli show very similar curves, E. coli 2091, for instance, shows a similar curve initially, but after an initial growth spurt demonstrates a plateau of stability in medium colour before again continuing a regular change in turbidity. E. coli 0111 also shows a later onset, but here an initial slow change is followed by a period of more rapid change before slowly declining. En. Sakazakii, by contrast, shows an initial gradient close to that of E. coli before illustrating a notable upward gradient and then an eventual downward curve.
A large number of micro-organisms show no particular reaction in the medium illustrated and the light band illustrated, but these show different growth patterns in other media, at other temperatures and in differing light bands. The difference is sufficient that it can be said that there is some medium, temperature and light band which will allow almost any micro-organism to be differentiated from any other.
To compare the growth curve with those taken from known organisms the start point of the curve is first regularised, i.e. the point at which any growth curve starts is detected since this may vary with number of organisms initially present. The new curve is then scaled along the horizontal axis (time) for the best fit (on the assumption that the temperatures or numbers of organisms may have been different) and then scaled on the vertical axis (quantity) for the best fit (on the assumption that the growth medium may not be identical). This process may be recursive and will provide as an end result a measurement of the degree of match of the body and end point of the compared growth curves. All of the available growth curves are matched against the new growth curve for a best fit and the closeness of the fit recorded.
If only a single organism is present it may be possible to get a very close match for at least one of the stored growth curves, however if more than one organism is present in the sample and grows in the medium the match will not be close and a second step takes place.
Taking the closest match to the current curve a second growth curve of known organisms is combined with the first curve to provide a combined growth curve. Again the curve from the second is scaled both on the time scale and on the quantity scale for best fit and a multitude of comparisons made from the stored growth curves to determine the overall best fit. If this is not within an acceptable range of fit (normally held as a difference in area of the current and the matching curves) the process may be repeated with the next most likely fit.
Eventually either one or more matches within the required standards are found, and a report of the best matches within the acceptable parameters are provided, with an indication of which is best and therefore most likely, or otherwise a failure report will issue, and a match by the dilution process which produced
The comparison process may be carried out on a computer, either with the aid of a GUI interface and user assistance with the scaling, or totally under software control, preferably using “fuzzy match” algorithms in known manner to determine the best match.
In some instances simply the initial slope of the growth curve may be sufficient to allow classification. This is particularly so where, while there may be multiple organisms in the medium, only one of them is required to be identified. Thus the comparatively distinctive initial growth curve for E. coli can be distinguished early and unless the other organisms in the medium must be identified an indication of the presence of E. coli can easily be provided.
While the process as described above assumes a single growth curve the measurements may be made at multiple different bandwidths of light, and the matching process may occur for all of the bandwidths used in the process or for combinations of them. This may be required because the growth curves for differing wavelengths may be very different for some micro-organisms and this allows them to be confirmed or eliminated as being present in the measured sample. Similarly even if a measurement at a single band is made that band may be chosen to best show the organisms which are being preferably sought.
Because the detection of organism growth is optical and by either transmitted light or reflected light it is necessary that the container for the organisms and the medium or analyte is consistent as far as distortion of the optical path and absorption of the various wavelengths concerned. Thus the container should be transparent at the wavelengths concerned and the area through which the optical beams pass should have consistently shaped walls which do not appreciably distort in normal use. The container should be packaged such that the area through which the optical beams pass is not easily contaminated on the outside by the user. At the same time the containers are single use items, so cost is a factor, and hence polyethylene terephthalate with a polyvinyl alcohol coating to reduce oxygen absorption is used. An alternate choice may be an acrylic (styrene-acrylonitrile) container.
To this end
It can be seen that over the period from 360 to 540 minutes after the start of the culture period large changes take place in both the turbidity and colour of the culture medium. To extract repeatably detectable events from these curves representing the growth of organisms within the culture a sequence of changes uniquely identifying a particular organism must be detected. In the culture growth pattern shown a series of events may be identified as:
A change in the ratio of blue to red colour (since these are the indicator colours for Resazurin).
A change in the turbidity of the culture.
Within these changes certain critical points can be mathematically identified, and in particular the inflexion points of the growth curves, as more clearly shown by the first and second differentials, are useful. One such set of critical points is identifiable by the sequence:
This equates to: detecting the existence of a negative slope on the normalised blue−red comparison, then detecting the next upward swing in the comparison, then detecting a rise in the scatter detected after the first point detected. If these requirements are met then E. coli are present and predominant in the culture.
This pattern can be followed for other organisms, namely a first colour set by the indicator in use, a final colour set by the indicator in use, an initial turbidity in the culture, a final turbidity in the culture. There will be a distinctive hue change event, normally gradual but not necessarily so. Portions of the hue change will exhibit variations which are of a constant pattern for that organism. In addition to this, as the cultured organism grows the turbidity of the medium will increase, however this increase will not be at a linear rate, rather, as the organism grows the saturation curve will exhibit changes which may be rapid and which may reverse. This is currently thought to be due to stages of growth in the organism in which some organisms tend to group or clump, and in so doing temporarily reduce the turbidity.
In
At 1904 the first hue inflection point of a current growth curve is selected, and at 1905 the second hue inflection point. At 1906 the comparison enters a loop in which the selected inflection points are compared against the values for each of the stored organisms by selecting at 1907 from any matches the next inflection in either hue or saturation at 1908 and comparing the relative time difference of this third point relative to the first two at 1909. If an approximate match is found at 1910 the match is stored as a potential match at 1912. If the comparisons are not completed at 1913 the relative spacings of the selected inflections is compared with known trace inflections for a merely adequate match at 1915, and if one exists it is marked and the comparisons continued until the selection is exhausted. For each potential match found the spacing of all inflections is compared with the current culture under examination at 1914 and where a match is found a result is returned at 1917. If no match is found a further classification process (not shown) utilising combinations of the organisms in similar manner to that of
Detection of the flexion and inflexion points in the curves of light transmission and reflection may be mathematically quantified to allow automatic detection of the points on the curves which can act as indicators for the organism(s) which are present.
Detection of the times at which this occurs in relation to the overall growth curve, in combination with irregularities in the change of hue provide a distinctive signature which is amenable to solution.
The samples are grown in a medium which has been standardised and calibrated against known organisms. Preferably the growth medium is held in a dry state in a rupturable container or pouch inside a sterile transparent plastics container of the type described in PCT/NZ2005/000139. Suitable growth media are described below. Whatever growth media is chosen it should be constant across a series of standard test containers and calibrated against known organisms so that the graphs shown above can be reliably used to ascertain the identity of micro-organisms from an environmental sample by comparing the growth pattern with the pre-calibrated graphs and machine readable data. To ensure reliable detection of a class of organisms, all the parameters (media, type of container, light source, optical filters or wavelengths chosen, incubation temperature, and the volume of the liquid sample) should be kept constant so that the only variable is the identity and quantity of the micro-organisms in the sample.
It should be noted, that these growth media compositions may be altered to allow for the specific growth and detection of various micro-organisms; the present examples relate to the detection of coliform bacteria (Table 1 and Table 2) and staphylococcal bacteria (Table 3).
One preferred growth media composition contains an indicator (e.g. Resazurin), an inhibitor (e.g. Bile Salts) of non-specific micro-organisms (i.e. those micro-organisms not being tested for), a protein source (e.g. Casitone—pancreatic digest of casein), an energy source (e.g. lactose), and at least one salt (e.g. NaCl). An example of this composition is described below; Table 1. In addition, a range of the percentage of each component of the composition has been given within which the detection of coliforms may still be carried out under the present invention. Another growth medium composition suitable for testing for the presence of coliform bacteria (including E. coli) is given in Table 2.
An example of the range of components used in a growth medium composition which may be used to support the growth and detection of staphylococcal bacteria is given below in Table 3.
It should be noted that the components of the composition of Table 1, 2 or 3 may be varied depending on the type of tests to be carried out. Where meat samples are to be tested the composition of Table 1 preferably contains no salt. In addition, alternative redox dyes or other indicators may be utilised. Further, the protein, salt, and energy sources of the compositions herein described may be altered to support the growth of various alternative micro-organisms.
The calibration graphs illustrate the growth (and death) patterns for coliform bacteria including specific E. coli species grown in vials or other containers containing a standard growth media (standard in the sense that a set of containers for testing environmental samples for the presence or absence of coliforms would contain identical amounts of the identical growth media composition (whatever is used as the reference media for the calibration graphs for that family of micro-organism).
The following description will describe the invention in relation to preferred embodiments of the invention, namely a testing container for assisting a user in manually taking and/or testing a sample. The invention is in no way limited to these preferred embodiments as they are purely to exemplify the invention only and it is noted that possible variations and modifications are readily apparent without departing from the scope of the invention.
Turning to
Disposed inside of the container 2000 is a sample collection member 2012 that may be removed from the container 2000 and used to collect a sample which potentially may contain the analyte of interest. Once the sample is collected, the sample collection member 2012 is returned to the container and intermixed with the liquid 2002, in conjunction with the reagent additive 2004 which is released via the compromising of the first barrier 2008. The contents of the container are then tested. Once testing is complete, the prophylactic additive 2006 is released via compromising of the second barrier 2010 to reduce the hazard presented by the contents, permitting the container and its contents to be disposed of with reduce risk of harm to humans or the environment.
In light of the above general description of the container 2000, the structure of the container 2000 will now be described in greater detail. The container 2000 may include a vessel 2014 capable of storing a substance 2016 (i.e. the contents of the container) in a leak proof environment. The vessel 2014 may be subdivided into a main compartment 2018, a first auxiliary compartment 2020, a second auxiliary compartment 2022, a first barrier assembly 2024, a second barrier assembly 2026, a first release assembly 2028, a second release assembly 2030, a cap assembly 2032, a filter assembly 2034, and a sampling assembly 2035. Each of these assemblies will now be described in detail.
The main compartment 2018 may be a generally cylindrically shaped structure having a first open end 2036 and a second open end 2038. The main compartment may be made of any suitable rigid or semi-rigid material, one suitable example being plastic, and is preferably made of a transparent or semi-transparent material. The main compartment 2018, when the first and second open ends 2036 and 2038 are blocked off, is adapted to hold a predetermined quantity (volume) of liquid 2002 without leaking. Although this amount of liquid may be any desired amount, in the illustrated embodiment, the predetermined volume of liquid 2002 is between about 50 ml and 1 litre, preferably between 100 and 500 ml, and most preferably about 120 ml.
Preferably the first and second open ends 2036 and 2038 each include attachment assemblies 2040A and 2040B for permitting the attachment, in either a permanent manner, or a removable manner, of the cap assembly 20132 and the first auxiliary compartment 2020 to the main compartment 2018. The attachment assemblies 2040A and 2040B may include threads, snap fit connections, quick-to-connect fittings, friction fit connections, and/or fasteners to permit the coupling of the cap assembly 2032 and the first auxiliary compartment 2020 to the main compartment 2018.
The first open end 2036 may include a lip 2042. The lip 2042 is preferably inward facing and annular in shape. The lip 2042 may be used to receive and retain a seal 2044 in place, the purpose of which will be described in greater detail below. Further, the main compartment 2018 may include an annular channel 2046. The annular channel 2046 may be used to receive and retain a filter 2048, the purpose of which will also be described in greater detail below.
The first auxiliary compartment 2020 may be a substantially cylindrical structure having an open end 2050 and a closed end 2052. The open end 2050 preferably includes an attachment assembly 2054 for cooperatively engaging and attaching to the attachment assembly 2040A associated with the main compartment 2018. Preferably the attachment assembly 2054 is adapted to non-removeably attach the auxiliary compartment 2020 to the main compartment 2018, although it is noted that it alternatively may removeably attach the auxiliary compartment 2020 to the main compartment 2018. The attachment assembly 2054 may include threads, snap fit connections, quick-to-connect fittings, friction fit connections, adhesives, and/or fasteners to permit the coupling of the cap assembly 2032 and the auxiliary compartment 2020 to the main compartment 2018.
The auxiliary compartment 2012 is adapted to store the reagent additive 2004 therein. The reagent additive 2004 may be any substance or compound, whether a liquid, solid, gas, or combination thereof. Preferably the reagent additive 2004 is a solid, and most preferably is a substantially dry powder. The reagent additive 2004 may be any substance or compound that provides at least a perceived benefit in the testing of the contents 2016 of the container for the presence of the analyte of interest. A few suitable examples of a reagent additive 2004 are a dye, an acid, a base, a chelating agent, a pH indicator, a growth media, oxidant, reductant, etc.
The cap assembly 2032 preferably includes a cap 2058. The cap 2058 may be a substantially cylindrical structure having an open end 2060 and a closed end 2062. The open end 2060 may include an attachment assembly 2064 for removeably coupling the cap assembly 2032 to the main compartment 2018. The attachment assembly 2064 may comprise threads, snap fit connections, quick-to-connect fittings, friction fit connections, and/or fasteners to permit the coupling of the cap assembly 2032 to the main compartment 2018.
The first barrier assembly 2024 is preferably disposed in the first auxiliary compartment 2020. The first barrier assembly 2024 may at least partially and preferably fully define the boundary between the main compartment 2018 and the first auxiliary compartment 2020. The first barrier assembly 2024 includes a barrier 2008 which may be used to seal off the second open end 2038 of the main compartment 2018. The barrier 2008 is preferably impermeable and water proof. The first barrier 2008 may be attached to the end of the main compartment 2018 by any suitable means, one example being by adhesive as is done in the illustrated embodiment, and another example being by mechanical means or fasteners. The first barrier 2008 is preferably designed to be selectively compromised, such as by rupturing or piercing, or by providing a mechanical opening (one example being rotation of the barrier to align apertures in the barrier with other apertures), to permit the contents 2002 of the main compartment 2018 to mix with the contents of the auxiliary compartment 2020. The barrier 2008 may be permanently installed in the container 2000.
The second barrier assembly 2026 is preferably disposed in the cap 2058. The second barrier assembly 2026 at least partially and preferably fully defines the boundary between the main compartment 2018 and the second auxiliary compartment 2022 and their respective contents. The second barrier assembly 2026 includes a second barrier 2010 which may be used to seal off the first open end 2036 of the main compartment 2018. The second barrier 2010 is preferably impermeable and water proof. The second barrier 2010 may be attached to the cap 2058 by any suitable means, one example being by adhesive as is done in the illustrated embodiment, and another example being by mechanical means or fasteners. The second barrier 2010 is preferably designed to be selectively compromised, such as by rupturing or piercing, or by providing a mechanical opening (one example being rotation of the barrier to align apertures in the barrier with other apertures), to permit the contents of the main compartment 2018 to mix with those of the second auxiliary compartment 2022. The second barrier 2010 may be permanently installed in the container 2000.
The first release assembly 2028 is designed to be activated to compromise the waterproof integrity of the first barrier 2008 and thus, initiate the mixing of the contents of the compartments 2018 and 2020. In the illustrated embodiment, the release assembly 2028 is disposed within the first auxiliary compartment 2020. The release assembly 2028 may include one or more piercing members, such as the teeth 2066 illustrated, which may be moved from a retracted position (shown in solid lines) to an extended position (shown in phantom lines in
The sampling assembly 2035 may be disposed in the cap assembly 2032. The sampling assembly 2035 may include a sample collection member 2012. The sample collection member 2012 may be any device useful in collecting a sample 2056. A few suitable examples of sample collection devices 2012 are swabs, sponges, pads, and liquid collection devices (i.e. small test tubes, scoops, eye droppers, etc.). In the illustrated embodiment, the sample collection member 2012 is a sponge of a non-natural (synthetic) nature. The illustrated collection member 2012 may take any shape, one suitable example being the hollow cylindrical shape illustrated. The sample collection member 2012 may be adapted to be removed from the container and used to collect a sample 2056 for testing, and replaced in the container 2000 for testing of the sample collected, as will be described in greater detail below.
The sampling assembly 2035 may include a sample collection member housing assembly 2078 disposed in the container 2000, the sample collection member housing assembly 2078 adapted to house the sample collection member 2012. The sample collection member housing assembly 2078 may include at least a first portion 2080 and a second portion 2082 adapted to sealingly engage each other to fully encompass the sample collection member 2012 in a sealed/enclosed environment.
The first portion 2080 may be adapted to removeably hold the sample collection member 2012. More specifically, first portion 2080 may include an attachment structure 2084 that removeably holds the sample collection member 2012 to the first portion 2080. Preferably, the attachment structure 2084 holds the sample collection member 2012 to the first portion 2080 such that the sample collection member 2012 can be released without the user having to touch the sample collection member 2012 and potentially contaminating the sample collection member 2012. In the illustrated embodiment, the attachment structure 2084 is in the form of a hollow cylindrical structure that is sized and configured to receive the sample collection member 2012 in a friction fit/interference fit manner.
The first portion 2080 may include a graspable member 2086 which is adapted to be grasped by a user. The graspable member 2086 is adapted to be grasped by the user to permit the user to remove the first portion 2080 from the container 2000, contact a surface or substance to be sampled with the sample collection member 2012, and replace the sample collection member 2012 in the container by brushing the collection member 2012 against the seal 2044 to knock the sample collection member 2012 off of the attachment structure 2084. The sample collection member 2012 then falls into the container 2000. The user never needs to touch the sample collection member 2012 thereby reducing the risk the sample collection member 2012 is contaminated by the user's touch.
The second portion 2082 may include a sealing surface 2088 or flange adapted to sealingly engage the seal 2044. The second portion 2082 thereby serves to at least partially and preferably fully seal off the main compartment 2010, thereby keeping the container dry above the height of the meeting of the seal 2044 with the second portion 2082. The second portion 2082 may be removeably disposed in the end of the main compartment 2018, and may be held in position by any suitable means, one example being by compressing the second portion 2082 into the seal 2044 by a compressive force applied by the cap 2058.
The second release assembly 2030 is designed to be activated to compromise the waterproof integrity of the second barrier 2010 and thus, initiate the mixing of the contents of the compartments 2018 and 2022. In the illustrated embodiment, the second release assembly 2030 is disposed within the second auxiliary compartment 2022 and the cap 2058. The second release assembly 2030 may include one or more piercing members, such as the teeth 2072 shown, which may be moved from a retracted position (shown in solid lines) to an extended position (shown in phantom lines in
Turning to
Preferably the container 2000 is subject to a predetermined minimum amount of ionizing radiation to sterilize the container. The predetermined minimum amount of ionizing radiation depends on how “clean” the manufacture wishes the container to be and is preferably greater than about 1, 2, 5, 10, or 20 kGy. Most preferably, more than about 20 kGy is used.
Referring to
Turning to
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Referring to
Turning now to
Preferably, the second auxiliary compartment 2022 is filled with a prophylactic additive 2006 that reduces the potential of the mixture 2016 to harm the environment or human health, to among other things, facilitate the disposal of the container 2000. For instance, as described more fully above, the prophylactic additive 2006 may be a disinfectant that kills any harmful bacteria that may be present in the sample, making the container 2000 suitable for disposal as non-hazardous waste. Alternately, the additive 2006 may be a second reagent needed to be added to the mixture 2016 to facilitate testing of the mixture 2016.
Of note, preferably the contents of the container 2000 are not mixed nor the protective layer 2090 removed, until just prior to sample collection. Accordingly, by following this procedure, and sterilizing the container at the end of the manufacturing process, the container 2000 can have an extended shelf life which preferably spans greater than a predetermined duration, a few suitable examples being greater than one year, two years, three years, four years, five years, six years, and even as much as greater than seven years.
In some instances it may be preferred to accommodate more than one sample within a container, perhaps because a smaller sample will still allow detection of contamination at the level required, perhaps because exactly identical development times are required for a comparison.
In such a case an insert capable of maintaining several samples separate through incubation is required, while yet allowing all of the cultures to be easily sterilized at the end of process.
A container formed in accordance with the present invention will exhibit one or more of the following advantages:
Increased shelf life;
Contains safe, substantially contaminate free or sterile water;
Easy to use;
Less expensive;
Reduced potential of contaminates being introduced into the container during sampling or testing;
Reduced potential that the contents of the container will cause harm to humans or the environment after sampling or testing is complete;
Container can be disposed of as non-hazardous waste;
Reduced handling and opening of the container required during testing;
Less exposure to handlers to the contents of the container;
Easy to manufacture.
While the invention is described in relation to water testing the invention is suitable for any material which may be dissolved, suspended or otherwise cultured in any fluid. Thus in the testing of crustacean a shellfish may be added whole or macerated to the water with an additional growth medium and indicator for the micro-organism concerned if desired. In the testing of milk powder the powder may be dissolved in water with added growth adjuvant and an indicator.
The apparatus itself may be readily portable and self-contained, and this together with the comparatively rapid response allows its use in situations where a normal laboratory result would be too slow to be useful, as for instance in determining whether flooding has caused a pathogen problem. For use in bulk testing situations an apparatus containing multiple vials, each with a light source and detector, may be provided. The outputs are sequentially monitored by a processing and recording apparatus.
While the optical system described provides white light and is sensitive in only three colour bands it is possible to substitute a system in which a variable narrow band filter is applied to either the source or the detector, allowing a continuous scan across the ultra-violet, visible, and infra-red spectrum.
Those skilled in the art will appreciate that in order to test for other micro-organisms that other growth media would have to be used and calibrated against known species of micro-organisms. Those media would contain reagents that favoured the growth of the micro-organisms to be tested but selectively inhibit the growth of other micro-organisms. (This is the function of the bile salts in the medium of Example 1).
It is to be understood that even though numerous characteristics and advantages of the various embodiments of the present invention have been set forth in the foregoing description, together with details of the structure and functioning of various embodiments of the invention, this disclosure is illustrative only, and changes may be made in detail so long as the functioning of the invention is not adversely affected.
For example the particular elements of the mechanism for measuring the optical reflection from the medium and contents may vary dependent on the particular application for which it is used without variation in the spirit and scope of the present invention.
Similarly the wave bands of light which illuminate the medium for the measurements may be white light with colour sensitive sensors or they may be sequentially applied bands of different coloured light with wideband sensors.
In addition, although the preferred embodiments described herein are directed to the measurement of micro-organism growth curves using multiple wave bands of transmitted light and a single reflected light band, it will be appreciated by those skilled in the art that the teachings of the present invention can be applied to other systems such as those using multiple differing bands for the reflected light and a single band for transmitted light, without departing from the scope and spirit of the present invention.
In addition, although the preferred embodiments described herein are directed to analysis of micro-organisms in an estuarine system, it will be appreciated by those skilled in the art that the teachings of the present invention can be applied to other systems such as water quality monitors, without departing from the scope and spirit of the present invention.
For instance the system may be adapted to provide checks throughout the supply chain of any perishable foodstuff. In such instances the foodstuff is handled as batches and samples are taken at each step in which the foodstuff batch is handled. Thus samples may be taken of all the inputs to the primary collection point (for instance for a seafood supplier of oysters: of the storage or wash water and the raw oyster flesh at packing), at the secondary distributor (if a batch is broken: swabs of the new container, of the decanted oyster fluid), at the final destination (at a hotel: sample of the oyster fluid as decanted, swab of the storage environment).
The source may, for instance, be a dairy farm 2705 supplying milk, a fishing boat 2706 supplying fish, oysters or squid, a market gardener 2707 supplying vegetable or a beef farm 2708 supplying beef or veal. The sources send the foodstuffs to what can be considered the primary source of supply such as a dairy factory 2709 supplying milk, cream or cheese, a seafood market 2710 supplying fish, surimi or smoked salmon, a produce market 2711 supplying potatoes, lychees or salad vegetables and an abbatoir 2712 supplying lamb, beef or alpaca carcases.
The product is from the primary supplier is bought by a secondary supplier such as a supermarket 2713, a hotel 2714, which may store the product in their cool room, a meat distributor or butcher at 2715.
The end product may be purchased from a supermarket shelf at 2716 and might be prepared in a hotel kitchen at 2717 or a consumer kitchen at 2718.
Shown at the bottom of the diagram is the water supplier 2719. The water supply is normally a critical factor at every stage since products may be washed or sprayed at several points in their travel or preparation. Continual tests of water quality at each stage may be essential element in a train of causation.
Naturally it will probably be impossible to culture a sample before the next step in the chain takes place, but at each stage the results of each test, identified against the batch number and by the type of test, are transferred to a central database. The central database is itself traversed by an application identifying those samples which exceed a maximum contamination level and can provide alerts to the supplier of the test results, the occupant of the tested location and any appropriate authorities.
Information on supplier or client such as their physical location, their contact, the details of the products they sell the level of alarm which should be provided if contamination is found and any other relevant details are entered at 2805. At 2806 are entered the details on the body or bodies which supervises the quality of the product or products which the supplier or client provides. This may for instance be a government body, a local body, a contracted authority or some other regulative authority. This information is then stored at 2807.
At 2808 the results from a remote self-reporting analysis unit may be received and automatically entered, at 2809 results may be hand entered at a call centre or an office, at 2810 the data on a known form may be scanned and OCR'd for entry and at 2811 the data from a cross-border database or other documentation database capturing information equivalent to a form may be interrogated and extracted. Such documentation may take the form proposed by UN/CEFACT (United Nations Centre for Trade Facilitation and Electronic Business)
The data received is processed by extracting or looking up at 2812 the GeoTech location of the test, the time the test was started, etc. At 2813 information on the supplier, the substance tests, the particular batch number concerned and the type of test is extracted and at 2814 the test results themselves are extracted. Once all the information is verified as correct the data received is stored in the database at 2815.
Once stored the information is subject to a continually running analysis process interrogating the data within the database. This process will, for instance, check at 2816 for newly stored data, check at 2817 that the batch results do not exceed the alarm level for that product, and if they do raise an alarm at 2818 which will result in the issuing of an automatic alert to the supplier and possibly to the regulatory authority concerned at 2819.
If no instant alarm is provided any previous analysis relating to that batch is checked at 2820 and any historical trend towards the alarm level as the batch has proceeded through the various supply points is identified. If the product trend is such that the next report on that batch is likely to exceed alarm levels then again an alarm is raised at 2821 and an automatic alert issued at 2822 to the supplier and possibly to the next destination for the batch if this is known from the information in the database.
If no such alarm is raised then at 2823 the product is checked for an unusual upwards trend level and physical proximity at one stage to other similar products which currently have an alarm indicated. This allows an alert to be raised at 2824 to allow an automatic alert at 2825 to a regulatory authority of possible future problems.
In this way a continual check may be kept on either a supplier or a particular batch of product from a supplier or a number of supplies in the same geographical area.
In the same way the results of tests for biological agents spread by other than foodstuffs may be made, for instance the system may be used for the detection and tracking of air spread or commerce spread pathogens and infections.
It is to be understood that even though numerous characteristics and advantages of the various embodiments of the present invention have been set forth in the foregoing description, together with details of the structure and functioning of various embodiments of the invention, this disclosure is illustrative only, and changes may be made in detail so long as the functioning of the invention is not adversely affected. For example the particular manner of implementing the method may vary dependent on the particular application for which it is used without variation in the spirit and scope of the present invention.
Although the invention has been described with reference to a portable incubator suitable for carrying out the method of testing of this invention, where the incubator can be taken to different locations, and samples taken and analysed on the spot, it is equally applicable that the incubator could be positioned at a fixed location for example in a factory or food processing plant, and the various sample bottles taken at different points of the food processing plant, and then carried to the incubator, and incubated. In such a factory application, the data base may be operated by a stand alone computer connected to the incubator.
However in most cases it is preferable that the database is remote from the various incubators, so that a number of incubators and samples can be taken across a large geographic area, and the results can be mapped by suitable analysis of the data stored in the database.
By storing the data in a database, it is also possible to track the spread of micro organisms, over a spatial area, but it is also possible to track occurrences of micro organisms over time not only in particular areas, but to track mutations, and other changes to populations to micro organisms. Throughout the specification reference is made to location information and date and time stamps of samples, and will thus be appreciated that the database or mapping aspects of this invention effectively rely on coordinates in four dimensional space time, which can be analysed in different ways as outlined above.
In addition it should be noted that a separate aspect of this invention is the fact that the same sample containers and incubator can be used to detect different types of micro organisms in the same sample, and this differentiation of the detected micro organisms can be used with the mapping applications, but can also be used as a stand alone test to determine the different types of micro organisms detected at a particular site, and where time permits, the enumeration of this different micro organisms at that site.
Throughout the description of this specification, the word “comprise” and variations of that word such as “comprising” and “comprises”, are not intended to exclude other additives, components, integers or steps.
It will of course be realised that while the foregoing has been given by way of illustrative example of this invention, all such and other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as is hereinbefore described.
The portable methods and apparatus of the invention are used in the testing of potentially harmful samples within the health industry. The present invention is therefore industrially applicable.
| Number | Date | Country | Kind |
|---|---|---|---|
| 593660 | Jun 2011 | NZ | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/NZ2012/000103 | 6/21/2012 | WO | 00 | 5/16/2014 |
