Coronavirus | Vaccines appear effective in preventing severe illnesses caused by COVID-19 variants of concern in India, says JIPMER Director

Prof. Rakesh Aggarwal says the surge is happening partly because ‘people are no longer taking precautions as seriously as they were previously’.

March 25, 2021 05:50 pm | Updated 10:55 pm IST

Rakesh Aggarwal

Rakesh Aggarwal

Professor Rakesh Aggarwal , Director, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry talks exclusively to The Hindu ’sBindu Shajan Perappadanabout the unique double mutant COVID-19 virus found in India, its implication for the country which is at the beginning of the second COVID-19 wave, the new manifestations of COVID-19, and the importance of vaccination.

What do the COVID-19 variants and double mutants found in India mean for the ongoing pandemic and second wave that the country is witnessing?

The genome sequencing data of the COVID-19 virus from 10 national laboratories in India made available on Wednesday show that nearly 7.7% of the nearly 11,000 specimens tested contained one of the viral variants.

In this context, it is important for us to understand what the variant viruses are, and what this detection means. Viruses develop changes in their genomes very often during their multiplication and spread. The progeny viruses with one or more such changes are referred to as ‘variants’. The appearance of variants of COVID-19 viruses in our population was not really unexpected.

The ‘double mutant’ simply means that this virus has two mutations, each of which has individually been seen in viruses from other parts of the world, except that it has both these mutations simultaneously. Such double-mutants are not rare. Based on the recent announcement, there is no reason to believe that this double mutant has any special characteristics for it to raise any special interest or concern.

Does this mean that nearly 7%-8% of all COVID-19 patients in our country have a variant virus? And should we worry about the variants of the COVID-19 virus?

No. I would not think so. The specimens tested were highly selected and preferentially included arriving foreign travellers and their close contacts. These groups would be more likely to have variants. Hence, the data in this select group would overestimate the frequency of variants. The real proportion of variant virus in all cases in our population should be lower than this. Of course, the rate would also be different across different geographical areas of our large country.

Genetic variations are very common in all viruses, including the COVID-19 virus. So, we do not need to worry about each and every variant. Detection of a variant virus is a matter of interest or of concern if the variant has some special characteristics.

Why are some variants a reason for concern? And are the variants detected in India ‘variants of concern’?

You would hear two terms: ‘variant of interest’ and ‘variant of concern’. The first — ‘variant of interest’ — refers to variants that appear to be associated with a special characteristic, but evidence is still limited. A ‘variant of concern’, on the other hand, is one where there is evidence supporting such association. These special characteristics of a variant could be an increased risk of transmission, causing more severe disease, failure of detection by the usual tests, or a higher risk of infection after prior infection or vaccination.

The three variants of concern have been detected in India. These had been first identified in the United Kingdom, South Africa and Brazil, respectively, and have been identified in several countries globally.

These are of concern primarily because they have an increased potential for spread from one person to another.

Fortunately, these variants are not associated with more severe disease or a higher risk of death. The good news is that simple measures, such as the proper use of face masks and of physical distancing, are highly effective in preventing the spread of these variant strains. Hence, we can still effectively control their spread by following these steps. Just that we have to be disciplined.

The other reason for concern has been the reports that some COVID-19 vaccines may not be as good in preventing infection with the South African variant. Again, fortunately, though these vaccines may not prevent mild illness caused by this variant as well, they still appear to be effective in preventing severe illnesses that need intensive care and ventilator, caused by these variants. Hence, it is prudent that those at a high risk of such disease, for example, the elderly and those with co-morbid conditions, and are eligible for receiving COVID-19 vaccines, get themselves vaccinated as soon as possible.

Is the current vaccination drive enough to control the pandemic?

The current COVID-19 vaccination drive is not really for controlling the spread, but to protect those who are likely to develop severe disease. Elderly people are more likely to develop severe disease, more likely to need ICU admission, more likely to need ventilators, more likely to die. The primary aim of the drive is to reduce the need for ICU beds, the use of ventilators, and deaths.

However, as immunisation continues and covers a large proportion of the population, it eventually will lead to a reduction in cases as well. In some small countries, such as Israel, where immunisation coverage is high, the disease rate has come down remarkably. Besides, case-control studies in the U.K. show that an extremely small number of vaccinated people get COVID-19. Increasing vaccination coverage will surely help.

The surge is a cause for worry. It is happening partly because people are no longer taking precautions as seriously as they were previously. COVID-19 is a highly contagious disease and spreads rapidly and exponentially.

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