A private sector initiative is conducting a study that will assess the viability of pooled swab testing for the coronavirus, as an alternative to individualized but pricier swab testing.
At a press briefing on Friday, Iloilo Rep. Janette Garin said the study was being conducted by the Philippine Society of Pathologists Inc. and the Philippine Children’s Medical Center under the watch of Project Ark, the private sector effort led by businessman Joey Concepcion, the presidential adviser for entrepreneurship.
Garin, a former health secretary, is helping Project Ark as chief implementor of its RT-PCR (reverse transcription-polymerase chain reaction) tests.
In pooled testing, one RT-PCR kit—recognized as the “gold standard’’ for detecting the presence of genetic material from the new coronavirus—can be used to test multiple individuals instead of just one.
Drawbacks
Laboratories combine samples taken from several people and test the multiple specimens together. If a batch tests negative for COVID-19, all those patients are cleared. If a batch tests positive, the specimens must be retested individually or in smaller groups.
Such tests could be used to quickly clear groups of people who are not likely carriers, such as students returning to school, or individuals in areas with relatively low active COVID-19 infection levels.
If the disease is prevalent in a community—more than around 10 percent, according to the American Association for Clinical Chemistry—pooled testing stops being useful because so many follow-up tests are likely to be required.
Pooled tests may also result in an increase in false negatives because combined samples are diluted, making it more difficult to pick up the virus material, according to the US Food and Drug Administration.
Reducing cost
Other countries are either implementing or at least considering this procedure. In China, the city of Wuhan, where the virus originated, was able to pool-test 6.5 million so far, according to a New York Times report.
According to Project Ark, pooled testing could make RT-PCR testing more affordable and accessible while producing faster results.
Garin said the study was expected to come up with the costing, the mechanism and the dissemination of research results among 21 laboratories by the end of July.
In an earlier briefing, she said the study was aimed at lowering the cost of RT-PCR testing to P350 from the present P2,000 to P3,500 in public hospitals, and P4,000 to P12,000 in private hospitals.
Should pooled testing earn the approval of the Department of Health, it can already be implemented in the second week of August, Project Ark said in a statement. —With a report from Reuters