What is pool testing and why is it being used?
What is pool testing and why is it being used?
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Pool testing, distinct from individual testing, tests a pool (or group) of people at the same time and is a form of testing that has been used for diseases like HIV/AIDS before the current COVID-19 pandemic. Normally, when a COVID-19 test is done using a nasal swab on a patient, that sample is then tested individually to determine if the virus is present, and this can take anywhere from 15 minutes to several days, depending on the abilities of the lab running the test. With pool testing, anywhere from roughly 3 - 50 samples are combined and all of the swabs are tested at once. If the test result from that pool test is negative, then all patients in that pool do not have the virus. If the result is positive, then each swab must then be tested one-by-one. Pool testing, also called "batch testing," is currently being used in order to test many more people for COVID-19 than individual tests alone. This is because instead of testing patients and then analyzing their samples individually to determine whether or not one patient has been infected with COVID-19, pool testing combines many samples and tests them at the same time. Pool testing has gained popularity in recent months due to surging numbers of COVID-19 infections around the world. This method gives laboratories the ability to save time, test greater numbers of people, and use their resources most efficiently. These tests are most useful in places with large populations but a lower number of COVID-19 cases within that population, including group settings like schools or workplaces. In places with with a high rate of infections, this testing strategy would not be as beneficial since most patients would be tested individually either way. Another potential hurdle is that pool testing might lead to more false-negative tests. This is because if a patient does have the virus and it is present in their individual test sample, that sample will be diluted when it is combined with the rest of the samples from the larger group, possibly to the point where the viral load is undetectable.
Pool testing, distinct from individual testing, tests a pool (or group) of people at the same time and is a form of testing that has been used for diseases like HIV/AIDS before the current COVID-19 pandemic. Normally, when a COVID-19 test is done using a nasal swab on a patient, that sample is then tested individually to determine if the virus is present, and this can take anywhere from 15 minutes to several days, depending on the abilities of the lab running the test. With pool testing, anywhere from roughly 3 - 50 samples are combined and all of the swabs are tested at once. If the test result from that pool test is negative, then all patients in that pool do not have the virus. If the result is positive, then each swab must then be tested one-by-one. Pool testing, also called "batch testing," is currently being used in order to test many more people for COVID-19 than individual tests alone. This is because instead of testing patients and then analyzing their samples individually to determine whether or not one patient has been infected with COVID-19, pool testing combines many samples and tests them at the same time. Pool testing has gained popularity in recent months due to surging numbers of COVID-19 infections around the world. This method gives laboratories the ability to save time, test greater numbers of people, and use their resources most efficiently. These tests are most useful in places with large populations but a lower number of COVID-19 cases within that population, including group settings like schools or workplaces. In places with with a high rate of infections, this testing strategy would not be as beneficial since most patients would be tested individually either way. Another potential hurdle is that pool testing might lead to more false-negative tests. This is because if a patient does have the virus and it is present in their individual test sample, that sample will be diluted when it is combined with the rest of the samples from the larger group, possibly to the point where the viral load is undetectable.
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What our experts say
Pool testing, distinct from individual testing, tests a pool (or group) of people at the same time and is a form of testing that has been used for diseases like HIV/AIDS before the current COVID-19 pandemic. Normally, when a COVID-19 test is done using a nasal swab on a patient, that sample is then tested individually to determine if the virus is present, and this can take anywhere from 15 minutes to several days, depending on the abilities of the lab running the test. With pool testing, anywhere from roughly 3 - 50 samples are combined and all of the swabs are tested at once. If the test result from that pool test is negative, then all patients in that pool do not have the virus. If the result is positive, then each swab must then be tested one-by-one.
Pool testing, also called "batch testing," is currently being used in order to test many more people for COVID-19 than individual tests alone. This is because instead of testing patients and then analyzing their samples individually to determine whether or not one patient has been infected with COVID-19, pool testing combines many samples and tests them at the same time.
Pool testing has gained popularity in recent months due to surging numbers of COVID-19 infections around the world. This method gives laboratories the ability to save time, test greater numbers of people, and use their resources most efficiently. These tests are most useful in places with large populations but a lower number of COVID-19 cases within that population, including group settings like schools or workplaces. In places with with a high rate of infections, this testing strategy would not be as beneficial since most patients would be tested individually either way. Another potential hurdle is that pool testing might lead to more false-negative tests. This is because if a patient does have the virus and it is present in their individual test sample, that sample will be diluted when it is combined with the rest of the samples from the larger group, possibly to the point where the viral load is undetectable.
Pool testing, distinct from individual testing, tests a pool (or group) of people at the same time and is a form of testing that has been used for diseases like HIV/AIDS before the current COVID-19 pandemic. Normally, when a COVID-19 test is done using a nasal swab on a patient, that sample is then tested individually to determine if the virus is present, and this can take anywhere from 15 minutes to several days, depending on the abilities of the lab running the test. With pool testing, anywhere from roughly 3 - 50 samples are combined and all of the swabs are tested at once. If the test result from that pool test is negative, then all patients in that pool do not have the virus. If the result is positive, then each swab must then be tested one-by-one.
Pool testing, also called "batch testing," is currently being used in order to test many more people for COVID-19 than individual tests alone. This is because instead of testing patients and then analyzing their samples individually to determine whether or not one patient has been infected with COVID-19, pool testing combines many samples and tests them at the same time.
Pool testing has gained popularity in recent months due to surging numbers of COVID-19 infections around the world. This method gives laboratories the ability to save time, test greater numbers of people, and use their resources most efficiently. These tests are most useful in places with large populations but a lower number of COVID-19 cases within that population, including group settings like schools or workplaces. In places with with a high rate of infections, this testing strategy would not be as beneficial since most patients would be tested individually either way. Another potential hurdle is that pool testing might lead to more false-negative tests. This is because if a patient does have the virus and it is present in their individual test sample, that sample will be diluted when it is combined with the rest of the samples from the larger group, possibly to the point where the viral load is undetectable.
Context and background
There have been many headlines in the news about "pool testing" for COVID-19. Pool testing for COVID-19 has already been implemented or is currently being considered in several places, particularly where there are large populations as well as limited time and supplies for testing. For example, Chinese health officials have used this method in Wuhan and Beijing to quickly test large numbers of people. U.S. federal health officials have also been discussing the potential for pool testing, informed by how this has been implemented in the Nebraska Public Health Laboratory when it was running low on testing reagents in March 2020 and has since reported 50-60% savings in reagents along with 20-30% savings in labor. Most health officials believe that the savings from pool testing will be limited outside of areas where the virus is rarely present. While pool testing alone is not expected to resolve the current bottlenecks in testing, this form of testing can be a helpful tool in some situations.
There have been many headlines in the news about "pool testing" for COVID-19. Pool testing for COVID-19 has already been implemented or is currently being considered in several places, particularly where there are large populations as well as limited time and supplies for testing. For example, Chinese health officials have used this method in Wuhan and Beijing to quickly test large numbers of people. U.S. federal health officials have also been discussing the potential for pool testing, informed by how this has been implemented in the Nebraska Public Health Laboratory when it was running low on testing reagents in March 2020 and has since reported 50-60% savings in reagents along with 20-30% savings in labor. Most health officials believe that the savings from pool testing will be limited outside of areas where the virus is rarely present. While pool testing alone is not expected to resolve the current bottlenecks in testing, this form of testing can be a helpful tool in some situations.
Resources
- Multi-Stage Group Testing Improves Efficiency of Large-Scale COVID-19 Screening (Journal of Clinical Virology)
- Group Testing and Sparse Signal Recovery (2008 42nd Asilomar Conference on Signals, Systems and Computers)
- Pooled testing with replication: a mass testing strategy for the COVID-19 pandemics (medRxiv)
- What is pool testing and how does it work? (Washington Post)
- Coronavirus Test Shortages Trigger a New Strategy: Group Screening (Scientific American)
- Pooling Coronavirus Tests Can Spare Scarce Supplies, But There's A Catch (NPR)
- Multi-Stage Group Testing Improves Efficiency of Large-Scale COVID-19 Screening (Journal of Clinical Virology)
- Group Testing and Sparse Signal Recovery (2008 42nd Asilomar Conference on Signals, Systems and Computers)
- Pooled testing with replication: a mass testing strategy for the COVID-19 pandemics (medRxiv)
- What is pool testing and how does it work? (Washington Post)
- Coronavirus Test Shortages Trigger a New Strategy: Group Screening (Scientific American)
- Pooling Coronavirus Tests Can Spare Scarce Supplies, But There's A Catch (NPR)
