To gauge the spread of the SARS-CoV-2 virus across the city amid the second wave, the BMC has decided to conduct around 35,000 to 45,000 covid-19 tests daily which was done since mid-February. Civic officials said for the past two weeks there has been a drop in the number of cases and Covid testing, due to which the daily positivity rate is below 10%. They are increasing it to check whether the virus has loosened its grip in the city.
According to the BMC dashboard, 5,24,348 individuals have been tested of Covid-19 in the last 20 days, which means on an average 27,597 tests per day. While an average of 50,000 tests was conducted per day in Mumbai during mid-April, they have now come down to an average of 20,000-25,000 daily.
Suresh Kakani, BMC additional commissioner said there is no doubt cases have decreased over the last two weeks. The Covid testing has reduced due to the strict restrictions implemented in the city. “We have to increase the Covid testing to understand the spread of the virus in the city. The cases are coming down, but we cannot assume the second wave is over. Earlier, the ratio of tests was RT-PCR and Rapid Antigen Tests was 60:40 which has now been reduced to 70:30 due to restriction,” he said.
About 35-40 per cent of the tests conducted per day are rapid antigen tests, which on average have a lower positivity rate than RT-PCR tests. Dr Om Shrivastav from Maharashtra Covid Task Force, said, “We can’t look at Mumbai in isolation. The cases have come down, but cases in the rest of the state or country have not. So what happens when restrictions are lifted? To say that the second wave is declining, we should wait till September end and then take a relook at the figures.”
Experts believe the city needs to keep up high testing numbers despite the lower positivity rate. Dr Rahul Pandit, another member of the task force, said, “I have always said we need to keep testing in large numbers even if the number of cases per day begins to drop. We may record a lower positivity rate during this time, but until we have a positivity rate below 5%, testing in high numbers is a better strategy.”
“This can be done by contact tracing in large numbers during the first 24 hours. We can target areas which have reported a higher number of cases, for example certain wards or localities in Mumbai. Eventually, we will not report cases in clusters and will see isolated positive cases. Even though numbers show an improvement in the situation, we cannot consider this and become slack.” Dr Pandit added.