Director of the Centre for Cellular and Molecular Biology (CCMB) Rakesh Mishra speaks exclusively to The Hindu about the concerns regarding the present surge of COVID cases in India and how the virus is manifesting differently in different people and the possible role of mutation in the current surge of cases. The CCMB has been doing analysis of coronavirus variants in India, studying the evolution of the virus, its mutations and strains ever since the pandemic hit the country. The CCMB is also part of the SARS-CoV-2 Genomic Consortia (INSACOG), comprising 10 institutes, set-up by the Central Government for sequencing of coronavirus genomes.
What explains the constant rise in cases in States such as Kerala and Maharashtra?
Though we have not found a concrete reason for it, there could be a couple of possibilities. One, this surge is caused by a more transmissible variant from outside India but we don’t have any such indication. Around 300 cases of new variants in the country are insignificant.
Second possibility is of a new variant emerging within the country. To confirm this possibility, we need to analyse larger number of people for a longer period. But since we have not found any common mutation or common change in the cases that are occurring, it is less likely to be the cause. And third possibility is that the people are not taking adequate preventive measures. Well, we feel that there are high chances of this to be true. It can lead to a chain reaction, and a sudden surge of cases.
Kerala controlled the epidemic very fast in the beginning, which means not many people got infected or exposed to the virus in the State and so not many developed the protective antibodies. It means a lot of people are vulnerable to catching the infection in the State. Though people across country are becoming complacent, same degree of indiscipline on people’s part in State like Kerala may lead to much more cases of COVID.
It is the same time of the year last year when Covid cases began to rise. Now again the cases are rising. Can we see another wave? How important is vaccination?
Another wave is always possible. As summers are harsher in India, people tend to stay indoors, switch on their ACs and coolers and then come out in the evening in masses. This could lead to rise in infection. But the co-relation between the last year and this year’s rise could just be a coincidence.
Looking at the trend of rising cases, one thing is very clear that these are because of carelessness at people’s part and we can easily stop the spread by following COVID -appropriate behaviour which include wearing mask, washing hands, avoiding large gatherings, avoiding indoor crowding.
Vaccination is a powerful tool and I think so far the vaccination drive has gone well. But now we may think of opening it up to private sector so that we can reach a large number of people in less time. If we can double or triple the number of people getting vaccines, we can stop or curb COVID spread effectively.
Covid is also manifesting differently in different people. Why?
This is the least understood part of COVID. Most of our time so far has gone into fighting the disease and managing it. Now we need to conduct serious studies to understand the clinical features of the disease, how it effects organs, what all organs it affects, etc. We need to study how it behaves in different people with different co-morbidities. We will take a couple of years to explain every aspect of the disease.
This virus binds to the Ace2 receptor, protein sitting in the surface of the cell, to gain entry into the cell. Depending upon the health condition of the person, and expression level of the receptor on a given cell type, it may cause more damage to some organs than others.
Recently strains from South Africa, UK, Brazil have been reportedly found in India. Is this a cause of worry for us?
The source of infection in most of these cases is from outside India. We checked several other samples of those who have currently tested positive for Covid, we have not found any of these variants in them which means there is no spread of the variant in the country. So, as of now it is not a cause of worry.
It also means that the recent rise in cases is not because of these new variants; it is because people have lowered their guards, they have become complacent, and are not following Covid norms.
How do we keep a track of the virus?
There are many ways we track a virus. We have found an interesting and easy way to see its presence and prevalence in a locality. We can detect virus RNA in a sewage sample, and by studying the number of RNA molecules present, we can tell what percentage of people in a locality have infection. It is a much faster way to track a virus. Recently, we were able to validate this way of measuring level of infection in the population by sero-survey method. We might be able to use this method to track other pathogens as well.
Can mutations in the virus lead to reinfections?
501Y mutation in the U.K. has shown an increase in the number of infections but not reinfection. In Brazil too, there are not many cases of reinfection. In fact, all over the world, the reinfections are fewer. But this is the current situation, it does not mean that more rounds of mutations will not lead to re-infections. So, it is important that we keep a tight vigil and prevent spread of the disease as much as possible by social vaccine of mask, hand hygiene and social distancing, especially avoiding clustering of people in closed space.
