'Start identifying people who need booster doses': PHFI President to govt

Given that Botswana and other South African countries have a considerable number of HIV-AIDS cases, there's ample opportunity for the virus to mutate substantially, says K Srinath Reddy

As more countries try to find out if they have been exposed to the new Omicron variant, public health experts are trying to determine if the new variant with 32 mutations can replace the existing dominant Delta/Delta Plus strains and wreak more havoc. In India, the debate has been centred around giving booster shots to the vulnerable population. K Srinath Reddy, president, Public Health Foundation of India, believes India should start getting ready for administering booster doses to some sections of the population. In an exclusive interview with Ishaan Gera, he shares his views on the new variant, booster doses, and vaccination for children. Edited excerpts:

They are 32 mutations to the Omicron variant. Is that a cause for concern? Or is it normal for the virus to have these many mutations?

Viruses do mutate. The number of mutations depends partly on the time they get to mutate in a human body. In the immunocompromised, or the very elderly and therefore, immunodeficient, the virus has time to have several mutations because it keeps replicating in large numbers. With multiple applications, it can also have mutations. In this particular case, it has developed 32 mutations of the spike protein, which means it has had ample time. Given that Botswana and other South African countries have a considerable number of HIV-AIDS cases, there’s ample opportunity for the virus to mutate substantially. It’s the location that makes a difference to the number of mutations.

The vaccine efficacy, studies prove, wanes after a few months. With most of our over 45+ population vaccinated nearly six months ago, do we need to be worried about new variants?

We are still dealing with the most prevalent strain — the Delta variant. The Delta variant is still fuelling cases — not too many, partly because many who were exposed to it during the second wave have acquired some degree of immunity. We also know that the rate of vaccination has increased in recent months, and that provides some degree of protection.

We see laboratory studies being conducted to see how effective the pre-existing antibodies or T cell immunity is against this variant. We know, for example, some of the vaccines developed originally against the wild virus, or the Wuhan virus, as well as against the Alpha variant, had diminished efficacy against the Delta variant. It is possible this particular variant could also have reduced efficacy. But it still doesn’t mean absent immunity. It is likely you may still have more than 50 per cent efficacy. It’s also possible that some of the impact the virus and vaccines have had on T cells and memory cells may also come into play, and immunity may get further enhanced by the trigger. The best prevention, of course, is to try and prevent infection in the first place.

Most of the developed world is authorising booster shots. Does India need to do the same for its over 60 and vulnerable?

The policy depends on how we define variability or vulnerability and how we actually set our priorities. It also depends upon the supply of vaccines and the availability of vaccination teams. There’s a fine balance here. I believe people who were vaccinated early on, for example, from January to April this year, namely health workers, the elderly, and the immunocompromised, should be identified for a booster dose. We should start getting ready for administering booster doses to them on priority. Even younger people, including children, should get the vaccination anyway.

Children’s vaccines are delayed in India. Is there a need to expedite the process?

We should still prioritise people who are more likely to get the disease based on any associated disease conditions or depressed immunity. Children have been found, the world over, to have less risk of severe disease. And, therefore, priority accorded to universal child immunisation is lower down the scale. To ensure children do not become transmission agents, we should encourage the use of masks, apart from vaccinating all adults, so that they will not expose children to the virus, whichever setting — home or school — they may be in. Gauging the risk at the moment, children do not immediately qualify as a priority group till other priority groups are exhausted.