Breaking: Over 50% of Delhi is seropositive for COVID. @ndtv @divyanshu @rishika625 @GargiRawat @nramind @bimalarya

This supports my earlier thread on protection through cross reactive immunity. Otherwise the loss of life would have been 50 times higher. https://www.ndtv.com/india-news/coronavirus-over-56-in-delhi-have-developed-antibodies-against-covid-19-says-fifth-sero-survey-2361847

The population of Delhi is 20 million. So far estimated deaths is 10,000. If 10 million have had COVID, we cannot reconcile the two numbers.

What are the factors besides lower age, less obesity, & underreporting that results in so much asymptomatic & mildly symptomatic COVID? https://twitter.com/vincentrk/status/1294404193294442502

Of these 4 factors, low viral dose is likely not operational in India because of the lack of masking and the impossibility of social distancing.

There is also no special reason why innate immunity will be stronger & no data on unique genetic factors that protect Indian people.

Which leaves us with cross reactive immunity from prior corona virus infections. I had raised this issue in August, and since then I have just become more and more convinced. https://twitter.com/vincentrk/status/1296404093343326209

It’s pretty hard to explain the two figures below when social distancing and masks have gone down dramatically in India in the last 3 months. And considering India has a population 4 times that of the US living in 1/4th the space. @FT @DrEricDing

At a time when LA is struggling for ICU beds, nothing close to this has been seen in recent months in major Indian cities.

So while we can discuss accuracy of numbers and talk data all day, the differences are so stark and essentially “unhideable”

And it’s not due to New Zealand style control of COVID by preventing the virus from setting foot in the country.

This thread is to explain an observed phenomenon with a hypothesis for which we have supporting data & new data that I heard is soon to come.

People in India must continue mask/distancing precautions and get vaccinated. Cross reactive immunity may not protect from mutant COVID. https://twitter.com/psampathkumarmd/status/1280875999547269122

Vaccines are absolutely essential and urgent even though the number of cases and deaths have decreased all across India. Vaccines can protect you from COVID including mutant variants of the virus, prevent spread, and provide more enduring protection. https://twitter.com/mayoclinic/status/1356323460637552640