Major flaws in PCR testing process
The findings of a study by the Epidemiology Unit of the Health Ministry, the Sunday Times learnt, have caused serious concerns at the highest levels of the Government.
The main finding -- 91 percent of the tests for COVID-19 victims were “Exit PCRs”.
The process is explained by health officials as follow- up tests ten days after a person in a household is confirmed afflicted with the coronavirus. Such tests, they point out, should have been carried out in 21 days instead, if positive results were to be achieved.
The position was also highlighted by the Sri Lanka Medical Association in a letter to President Gotabaya Rajapaksa this week. It said that Exit PCRs "do not measure the extent of transmission in the community" -- a major contributory reason for the uncontrollable spread of COVID-19.
The study was done from May 21 to 31 this year. During this period, the study revealed that there were 34 deaths a day and that there is a slight increase of daily cases compared to the previous week (in the last two days cases exceeded the 3,000 range).
During the period in question, two studies were conducted to find out the increase of cases that could be due to Exit PCRs.
On May 21, a total of 1,981 cases were used for the study and the results were that 1,808 (91.27 percent) were Exit PCRs. Another study conducted on May 31, using 2,752 cases, revealed that 2,269 (82.45 percent) were Exit PCRs.
Following the studies it has been highly recommended to extend the quarantine from 14 to 21 days and conduct exit PCRs on the 21st day of the quarantine as more than 80 percent cases were reported during exit-PCRs.
A study of the lab reports also indicated there are still about 7,000 PCR samples pending as of now. Therefore, it has been suggested to immediately clear the backlog of PCR samples as a matter of priority to allow real-time data analysis by discarding sample taken more than 72 hours before the tests.
Among the recommendations is to segregate community samples into exit PCRs, random samplings, ILI /SARI (hospitals) or otherwise so that the assessments can be fine-tuned.