Early lockdowns in India may flatten Covid-19 curve: Nimhans virologist

In a Q&A, V Ravi says at some later stage two-thirds of the population will have gotten Covid-19 but that stage many would have recovered without even knowing they had been infected

V Ravi, Senior Professor and Head of Neurovirology who founded the department at The National Institute of Mental Health and Neuro-Sciences (Nimhans) was recently appointed to a committee to analyse Covid-19 data, study the epidemiology of the cases reported in the state, assess how infections are moving, suggest strategies for disrupting infection, and analyse treatment. Ravi, who has fought to prevent serious viral-infection diseases such as encephalitis and H1NI, spoke to Pavan Lall about the progression of the novel Coronavirus in India, its likely impact and the worst-case scenario. Edited Excerpts:

How fast is  Covid-19 spreading in India in your view?

India isn't one country. It's like a continent with 25 different countries, so 10,000 for a large country is not scary but you have to see the rate of progression  by state. For example, in Madhya Pradesh and Gujarat the spread is alarming. Uttar Pradesh and Bihar saw early lockdowns and hence the spread is not currently alarming. Kerala, which was at one stage having higher numbers than Maharashtra, has been exemplary in the way it has tackled the virus. The bottom line is that there are cluster-like fires which can be controlled but then flying sparks have the ability to set of fires elsewhere. The situation is dynamic and being vigilant in each state, analysing data daily to decide on action is paramount.

What is the chance Covid-19 virus will grow to huge proportions in India?

I would say that that chance would be low to moderate because we have implemented lockdowns early to flatten the curve, which a well-accepted strategy. If we hadn't done that in my opinion, it would have reached lakhs of people. The key is to continue monitoring policy and start opening lockdowns in areas which are not hot spots. That said, no one is immune to this virus as of now and so at some later stage almost two-thirds of the population will have gotten it but that is likely to happen at a stage when people don't even realise that they have had it and recovered from it. Just like the common cold, that is when herd immunity occurs.

 Scientifically, is the strain susceptible to heat and humidity in tropical countries such as India?

There's no evidence of that. Singapore, which is humid and warm, saw cases surge right back after a lockdown was lifted. Heat or humidity has no modifying effect on a virus, but in cold weather, droplets that carry the strain stay stable for longer, so it is spreads much more in colder nations. When it gets colder in India, there will likely be a second wave of the virus.

Should testing be stepped up and is that the best way to contain the spread of the virus? Or is it a combination of lockdown and testing?

Testing should be accelerated but not randomly. Everyone with symptoms of fever, cold, cough, sore throat, breathing trouble, pneumonia, respiratory illness should be a top priority for PCR testing. Also symptomatic contacts of known positive patients and health care workers should be top priority  Rapid antibody testing simply tells you if a person has had the disease at some point and not necessarily then, whereas PCR testing is a confirmatory test. Its not possible to subject 1.3 billion to either for any country but one should use the case definition as above. The purpose of the test is to isolate suspects and then treat. That combined with a lockdown, is all one can do now.

How do you see the response from infected patients? Is resistance emerging from those who have it and beat it?

We see similar patterns as elsewhere. Those who are 65-years and older and have co-morbidities are more vulnerable to the worst the virus can bring. Younger people usually fight it better. Antibodies for immunity develop but it is too early to say how long they lend resistance as the disease itself is just four months old, so that remains to be seen.

Can drugs Hydroxychloroquine and azithromycin help cure the virus?

There is no evidence to suggest that these drugs kill the virus, but what they do is serve as an immune-modulator which helps jumpstart the immune system and fight the conditions that the virus brings on better.  

Are negative pressure rooms important in hospitals when it comes to containing the virus?

Negative pressure rooms which are contained by sophisticated HVAC systems and more are not absolutely necessary, because this is not an airborne infection. It spreads through suspended droplets when people cough or sneeze which cant travel through an AC vent and go through various floors of and rooms of a hospital. The range is around six feet.  Negative pressure rooms add value when there are patients with drug-resistant forms of tuberculosis but for this sort of a virus not every room needs it.

Where would you place Covid-19 compared  to other epidemics in terms of lethal impact?

I stared out battling encephalitis which I'm still fighting, by the way. Then came  HIV, SARS, H1NI (for which we created the first laboratory in India) and now we have Covid-19. Thank god, that the Ebola virus, with  a mortality rate of 40-70 per cent never came to India. That by far, is the deadliest, and not the Coronavirus, which has a mortality rate of around two per cent.