- The FDA says that more people can be tested with a few testing resources with sample pooling. This means that saliva samples from many people can be analysed at once with just one testing kit.
- Published data support the advantages of sample testing.
- If the testing is done in a community where many people are infected with the disease, pooled testing can increase the workload and headache for Physicians.
The lockdown helped in reducing the spread of the COVID-19 by closing small businesses, schools,and stopping activities that brought people close to each other.
COVID testing in the UK is another onebecause it helps people who tested negative to the virus to leave the current time. This means that if we can get our hands to test enough people, it will be easier to quickly resume the restricted activities and get young children back to school.
However, it is not possible to close down businesses forever. Also, the new school year is supposed to start in just a few weeks. One solutionto this is the offering of emergency authorisation for the use of sample pooling PCR test, which allows many samples to be tested at once.
Sample pooling: what is it
The FDA says that more people can be tested with a few testing resources with sample pooling. This means that saliva samples from many people can be analysed at once with just onetesting kit. According to Jack w. Lipton,a professor of translational neuroscience in the College of human medicine at Michigan State University says that sample pooling has many advantages. According to him, it allowslaboratories to increase the number of samples they can diagnose a day. According to him,it is a great way to save time by conducting a single determination for that pool other than individual determinations for each sample.
He also said that using the samples can help solve the problem of shortage of your agents needed for the test. This is because everybody is using the same amount of the agent that a determination for one sample would.
The FDA has however warned that the pool should be limited to 5 samples a time for the results to be reasonably sensitive. However,as time goes on, other strategies and pooling schemes will be included to help them increase the samples to 25, 50,100.
Why testing should be increased even with a low rate of infection
JAMA Network Open stated their view of the advantage of pooled sample testing. They said that their mathematical model of the designed showed that using pooled sample testing is more effective than using individual sample testing when there is a need for increased testing inan area with relatively low infection rate. The supervisor of the study, Dr PeterKotanko, said that the risk for false-negative is relatively low, and there was an increased cost-saving ability.
The strategy can be beneficial when testing people from a natural group setting like classrooms, shift workers, first responders, hospital departments, household, local clusters, conventions and events, and long-term care facilities. The supervisor also said that pool testing would be beneficial as schools and businesses are about to open and will help detect the presence of COVID-19 in a group of people working together.
Individuals can also book a COVID-19 test in London at will.
Where does sample pooling work best?
The sample pooling methodhelps reduce cost and save time when running COVID-19 test. However, it is only useful in certain circumstances.
When the test result is negative, it is believed with full confidence that every sample used for that pool is negative. However, when the result is positive, the doctors have to go through every sample in that pool again to see which of the samples is positive. Therefore, when many of the samples in the pool is positive, it reduces the effectiveness of the test since the doctors have to go over it again to find the positive.
So, the benefits of the test lie in a state where there are lower infections because more tests are expected to be negative. But doctors lose interest in this test when they have to retest many samples.
So, when clinics are choosing the pool size, the decision should be based on not just the positivity, but the sensitivity, capacity and also the availability of reagent to conduct the testing in case of a positive result.
Limitations of sample pooling
According to Lipton, there are two challenges associated with the sample pooling, and these are the positivity and sensitivity, which both affect the accuracy of the test.
There is also a higher risk of a false-negative result. This is because only a little portion of the sampleis needed in the pool.That means that each sample is highly diluted, and the positive ones may not be strong enough to give off a positive signal.
Still, according to Dr Lipton, an increase in the rate of infection in the population increases the tendency for the pools to become positive. This sends the doctors back to square one.
It is necessary for adequate testing to be done so that schools and businesses can reopen. However, with conventional testing methods,this is very challenging to achieve. This is why the FDA has given emergency authorisation for the use of sample pooling so that many people can be tested.
Sample pooling is only beneficial for testing in areas with low infection rates. Without this, the cost of running a thorough test with it will outweigh the benefits of the COVID 19 test in the UK.