Its a method called pool testing, or pooling, and its aimed to provide better insight on exactly where the coronavirus hotspots are and arent for a communityits not a better way to test you individually. If a community knows there are cases, it can enact appropriate precautions quickly. Thats important in this very communicable disease.
How does pool testing work?
Also known as batch testing, pool testing is different than other testing methods since it takes the testing samples from many people at once and tests them for coronavirus together. This is how it lowers the need for supplies (like the reagents required to do the test) and time.
If the test comes back with the presence of a positive reading for the virusamongst the group as a wholethen each person in that testing pool would have to be tested individually and have their results analyzed to see whose sample amongst the group has the positive result.
If the test is negative, then the testers are done with that group and can move on to the next.
What are the benefits of pool testing?
Whats the draw? If everyone is negative, then youre done, Ashish Jha, director of the Harvard Global Health Institute at Harvards T.H. Chan School of Public Health, told The Washington Post .
Pool testing was first used back during World War II, when people were being tested for STDs such as syphilis and HIV. And now it could come in handy again, to help provide much-needed speed and insight on where and how the pandemic is spreading.
You are able to target many more people at once to test, which is a major pro, yet there are some drawbacks that come with pool testing, too.
What are the drawbacks to pool testing?
The trade-off is that theres reduced sensitivity. Its kind of a balance, said Benjamin Pinsky, director of the Clinical Virology Laboratory at Stanford Universitys School of Medicine also told The Washington Post. Samples with low viral loads are more likely to pass through undetected when in a pool than through individual testing methods, he explained.
Researchers have suggested that pool testing works best for groups that are between three and 50 people. The larger the pool, the more likely a positive case with a low viral load will be too diluted to lead to a detection of the virus within the results. Researchers are still working to improve methods and find ways to make diagnosing a positive case from a pool easier.
So, does pool testing work?
Pool testing could work due to the benefits of reducing need for resources and time, but there are the drawbacksthe pandemic is too vast and has infected too many people, so its likely a large amount of individual testing would still need to occur.
Pool sampling works best in large populations in which the infection rate is lowand there may not be that many of them at this point. If you are working with a large group where a number of people may be positive, its not helpful to group them together, because the group will be positive and then individual testing still needs to be done.
Right now, some labs are now preparing to undergo clinical pool testing, pending approval from the FDA. It remains to be seen how those efforts pan out and whether its a useful strategy to strategically roll out in the US.