Methods of Pool Testing During the Pandemic

The pool testing method is a testing process used in tackling the COVID-19 pandemic. It is used after the Food and Drug Administration (FDA) approval. Pooling samples facilitates testing labs to speed up testing inefficiency and number while using fewer testing tools. It is certainly a cost-effective method and can be widely used during COVID-19 pandemic waves to help fight the infection with full vigour. Pool testing strategies rely upon the origin of infection in the community, thus reducing test tenderness. Hence, the pool testing method needs to understand its usefulness in this COVID-19 pandemic fight. 

What is Pool Testing? 

Pool testing is a method wherein biological samples such as blood, urine, tissues etc., taken from various subjects are collated and tested in a singular test. This testing method considerably leads to the betterment of public health efficiency, screening and population-stage inspection of diseases. The pool testing method was Introduced in the 1940s and has been applied to various applications like screening donated blood or regional human immunodeficiency virus (HIV) inspection.

Now, the samples collected through this method of pool testing of COVID-19 allow the doctors and researchers to protect material and human resources, specifically people working at testing labs and public health avenues. Even developed countries such as the U. S. have been facing an acute shortage of testing facilities such as kits and pre-analyzing testing supplies, licensed lab personnel working for testing centres equipped with required credentials. Resource conservation is noted to be a strong point of pool testing strategy in regards to the continuous hike in covid cases throughout the COVID-19 pandemic. 

Pool Testing Method:

The pool testing method is a process basically used for making the testing for communicable diseases of large numbers of people cost-effective. Simply, pool testing functions by grouping a large bunch of separate samples into a common pool and then conducts tests on the samples figuring out negative and positive results accordingly and following the process of contact tracing or other methods to constrain the transmission chain. Thus, this method of pool testing is quite efficient and direct in detecting active cases out of a particular sample. 

The following example very well explains the pool testing methodology using the best pool size: 

A prevalence of 0.5 % active disease shows that there are 50 active cases in a population of 10,000 people. Now, if we attempt to test the 10,000 in 50* 200 pools wherein all the positive patients are alone in their pools, we would anticipate 50 of the 200 pools to test positive. But if the covid cases are grouped, the results would be a lower number of positive pools. Next, some addition is done: 50 positive pools are found, so now, 1,700 tests would be conducted to obtain results for 10,000 people, i.e. an 83% decrease in the number of tests performed. 

Pool Testing Sample:

The method of pool testing samples includes blending multiple samples in conjunction in the form of a batch or pooled sample, which is then placed for testing using diagnostic tools. The pool testing method certainly facilitates increasing the count of individuals being tested within limited resources. If we see an example, multiple tests, maybe four or five, could be carried out together using the resources of a single test. On the contrary, the pool testing method also has a negative aspect: more false-negative results due to sample dilution resulting in lower genetic and viral constituents. Nonetheless, this method of pool testing works pretty well during lower levels of cases where greater negative results are expected. 

The Food and Drug Administration (FDA) believes that pool testing samples may be standardised and authorised in some specific COVID – 19 testing with required reduction and validation. The Food and Drug Administration (FDA) has given out certain approval recommendations for tests which intend to use pool testing samples in the Emergency Use Authorization (EUA) Templates.

Therefore, it is much needed for the test developers who are seeking approval for their tests for use collated with pool testing samples should approve their test for such use, keeping in mind the validation recommendations mentioned in the Emergency Use Authorization (EUA) templates, and submit an Emergency Use Authorization (EUA) request to the Food and Drug Administration (FDA).

Conclusion

Pool testing can be considered an apt attempt in regions with lower levels of COVID-19 disease. This method is quite handy in places where the testing facilities might expect a large majority of the population to turn out to be negative but the case might not be so. Controlling the spread of the virus requires testing infectious people and tracing contacts for anyone expected to be exposed to infected people, followed by isolating the former. Thus, the pool testing method is quite effective in managing the COVID-19 wave at a particular level with much efficiency.