'Viruses can really surprise us': Dr Ashish K Jha on whether Covid-19 can become more lethal

Dr Ashish K Jha said there is plenty of historical evidence of viruses that evolve to become more lethal.

"There is a widely-held belief that viruses always evolve to become less lethal over time. I wish that was true. I don't think that's true," said Dr Ashish K Jha, White House Covid-19 Response Coordinator on Day 1 of the HT Leadership Summit 2022 in conversation with R. Sukumar, Editor-in-Chief, Hindustan Times. The five-day annual summit kicked off today. (Also read: India's Covid vaccination was one of most impressive in world: Dr Ashish K Jha)

Dr Ashish K Jha, White House Covid-19 Response Coordinator

According to WHO, over 300 Omicron subvariants are currently circulating in different parts of the world causing a spike in Covid infections. Some of these variants are immune evasive, and some are highly infectious, but Covid over the years seems to have evolved so far to be less deadly than the original virus. Is there a possibility of a deadlier variant of the virus emerging?

"...there is plenty of historical evidence of viruses that evolve to become more lethal. I would say that I am very pleased to see, Omicron in general has been less severe than Delta, but if you think about it, Delta was probably more severe than Alpha or the original variant. So, we did see evolution to be more serious. Now we see evolution as less serious.

Dr Jha hoped that the evolution hereon would be either the same or less serious over time but he said he would not assume that is the given because viruses can really surprise.

'Virus is changing'

On being asked if the new emerging variants are a big concern going forward, Dr Jha said: "Right now variants are a concern. Here's how I think about it. We are seeing very rapid evolution of this virus. When you speak to most virologists and you look at historical evolution of the viruses, the speed with which SARS-Cov-2, the virus that causes Covid-19 is evolving, is really remarkable."

The expert said that the primary reason behind that is we have "so much immunity across the world between vaccinations and prior infections that it is putting an evolutionary pressure on the virus to find a way around that immunity."

He said that this is the reason we are seeing emergence of more and more immune-evasive versions of the virus variants.

"The good news is that as virus is changing, so is the humanity; we are able to do things - update vaccine, keep up with the virus and in fact get ahead of the virus," said Dr Jha.