More testing imperative

Experts say adequate samples not tested in third phase as cases spike

Of the 1,003 cases of COVID-19 diagnosed till May 27, 777 were imported — or those with travel history — and the rest contacts of the imported cases. The tally may increase as most of those who have got infection from the primary cases will be in the incubation period at present.

In the second phase of the disease that began with a cluster of cases in Pathanamthitta on March 9, most of the imported cases were expatriates. In the third phase from May 7, with the easing of travel curbs, the imported cases included those coming from other States as well. When there were 502 positive cases till May 7, it doubled in just 20 days.

Medical professionals aver that though the number of positive cases has increased in the third phase, the samples tested are not correspondingly high. Till Wednesday, testing was done in only those with symptoms at the end of two weeks’ quarantine. As most COVID-19 patients are asymptomatic or have mild symptoms, this strategy is likely to miss these patients who may spread the disease in the community.

The State had shied away from testing more numbers till now and an analysis of the data on the State website indicates the State is going down from what has been a relatively good control over the disease, says Padmanabha Shenoy, clinical immunologist and rheumatologist.

The positivity rate has gone up over the days as the number of cases increased while the testing has not gone up from the average of 1,500 tests a day. Unless more people with mild symptoms or may be asymptomatic are tested in a scientific random manner, the State is likely to lose control over the spread of the virus, Dr. Shenoy says.

Even though the Chief Minister on Wednesday indicated that the government will be conducting 3,000 more tests, there is much to catch up on, he adds.

IMA president Abraham Varghese has urged the government to make transparent all data regarding the disease, especially epidemiological analysis, to enable professional bodies to conduct studies for a better understanding of the disease.

The Health Minister had indicated that there are cases for which linkages have not been established, which is worrisome. In the new spiral of the disease too, the disease transmission in certain patients has been a worry for health authorities.

The sentinel surveillance in the State is expected to pick up these very cases that had puzzled surveillance. A health official told The Hindu that 40% of asymptomatic expatriates would be tested in this strategy in a scientific manner.