Dr. Soumya Swaminathan, Chief Scientist at the World Health Organisation, tells The Hindu in an interview that the fight against COVID-19 is likely to be long-term, and lockdowns alone cannot be effective unless combined with other health measures. Dr Swaminathan, who has worked in research on tuberculosis and HIV for 30 years, was Director-General of the Indian Council of Medical Research from 2015 to 2017. Edited excerpts:
What do we know so far about how SARS-CoV-2 is spreading around the world?
Viral evolution and transmission dynamics can be studied by analysing genetic sequence data. There are over 4,500 viral sequences currently deposited in the GISAID platform, with around 10 Indian strains. What we see is, that over time, there is some variability in the strains. That is to be expected, as all viruses develop mutations as they transmit from person to person. What is not being observed so far is any mutation on any of the important sites of the virus, such as the spike protein or in the RNA polymerase or protease enzymes, which are relevant for drug targeting and vaccines. So we believe whatever strategies are now being used to develop both therapeutics or vaccines are not threatened by any changes in the virus.
What does the evidence tell us about the effectiveness of lockdowns as a strategy?
The WHO has laid out quite clearly that physical distancing, of which one extreme form is a lockdown, does help bring down the transmission of the virus in the population. What they saw in China [