‘Covid-19 peak likely in July-August’: Dr SK Sarin

Would this mean that we will continue to see an increase in the number of cases?

The lockdown has only delayed the peak, which is likely to come maybe in July or mid-August.

At present, the country is seeing an ascent in the number of Covid-19 cases. It will remain so as long as the reproductive number is more than 1 (meaning each infected person transmits the virus to more than one person). The plateau will come only when one person infects one person, the decline will start when one person is infecting say 0.5.

What is the worst-case scenario for Delhi and is the city prepared?

We are already in the second scenario that the committee had talked about of 500 cases being reported in a day. And, Delhi is prepared for the third scenario of 1,000 cases being reported in a day as well.

It is really one of better controlled and monitored cities with a very well organised reporting and testing system. We are doing almost 5,000 tests a day now, which was anticipated for this scenario. And, it can go up to even 10,000 when required.

Delhi is doing well but it is a very vulnerable city due to movement of people from other states. And it will remain a vulnerable state for a year or year-and-a-half. The people of Delhi will have to be extra cautious.

So, what is the way forward?

Ideally, the lockdown should have lasted 12 weeks as we learnt from Wuhan, China but we had it for about nine weeks. I think it was only possible and people were accepting of it because it was done in an incremental manner.

We have to be extra-cautious for a surge in cases mainly because of the travelling migrant workers and slightly early easing of the lockdown restrictions. There will be a surge but is acceptable. The numbers are not a cause of concern, the deaths are.

Also, at any given time in a community 30 – 50% is the hidden number of cases. So, as a way forward I strongly suggest that antibody tests be done.

How will antibody testing play a role in opening up the lockdown?

Today’s green zones are probably the most dangerous zones for tomorrow because there is no exposure in people living in these areas and they will drive the future waves of infections. Today, red zones are probably better because more people have been silently exposed and they would have developed the antibodies to fight off the infection.

Now, to understand whether a red zone can be more open tomorrow or a green zone become restricted we need to do antibody testing. It will help us identify the areas where we have to pay more attention next month or the month after.

Apart from the antibody testing, do we need to test more as the restrictions are eased?

Our testing strategy needs to improve. And that would include making the swab tests available at all major hospitals rather than the samples being sent to certain specified labs.Delhi is already doing about 5,000 tests a day and this can be increased up to 10,000.

Apart from the RT-PCR {Reverse Transcriptase-Polymerase Chain Reaction} nasal swab test, our testing strategy will have to include blood antigen test. If you are going to test a large population, the test has to be cheap, rapid and feasible. The current nasal swab tests are not that friendly and feasible.

It should be available in the next few weeks’ time. Plus, we also need the antibody test like I have said earlier.