Too late in day to roll out booster jabs, say experts even as Centre showcases data on US vaccines’ efficacy
Most immunisation experts say Centre’s decision to roll out booster doses was taken in absence of robust evidence on type of vaccine to be used and that it may be too late to make much difference
Even as India recorded 1,94,720 fresh Covid-19 cases and 442 deaths on Wednesday, the Union Health Ministry showcased the analysis of mRNA vaccines in New York to point out that a fully-vaccinated population had between 90.2% and 95.7% lower chance of being hospitalised with Covid-19 as compared to the unvaccinated population. The Ministry’s joint secretary Lav Agarwal contended that this showed the effectiveness of vaccines against the infection.
In India, however, the Union government has not begun administering any mRNA vaccine such as Pfizer or Moderna or a non-mRNA vaccine alternative Covovax. India either administers Covishield, which is an adeno-vector vaccine, or Covaxin, an inactivated virus vaccine.
Messenger RNA vaccines work by introducing a piece of mRNA that corresponds to a viral protein. Using this, cells produce the viral protein. As part of a normal immune response, the immune system recognises that the protein is foreign and produces specialized proteins called antibodies.
Earlier, a Union government health expert stated that booster vaccine doses won't stop the rapid spread of the Omicron variant of the virus as it is “almost unstoppable and eventually everyone will get it”.
“Covid is not a frightening disease anymore as the new strain is milder and is leading to much less hospitalisation. We are dealing with quite a different virus. It's much milder than Delta, as you all know; not only that, it is practically unstoppable,” said Dr Jaiprakash Muliyil, epidemiologist and chairperson of the Scientific Advisory Committee of the National Institute of Epidemiology at the Indian Council of Medical Research.
Niti Aayog member Dr VK Paul stressed in a Health Ministry press conference that Omicron is not common cold. “It's our responsibility to slow it down. Let's get vaccinated, whoever is due. It's a fact they (vaccines) are helpful to an extent.”
India rolled out booster doses of Covid-19 vaccines for healthcare workers and those above 60 from January 10, but there are still questions over the benefits of giving additional doses of the same vaccine that people have already taken. There is little data to support the rationale behind giving the same booster dose in preventing transmission of the Sars-CoV2 virus.
Virologist Gangandeep Kang has stated that boosters in the elderly and those otherwise at high risk will provide the greatest decrease in severe disease and death in all parts of the world if doses and vaccination are not constrained, which is why ‘precautionary doses’ make sense, even in the absence of evidence from India on waning vaccine effectiveness.
In a report in Times of India, Kang advocated for evaluation of Covovax and Corbevax as third doses as soon as possible. She pointed towards two studies published in Israel which underscored that a booster dose of the Pfizer/BioNTech Comirnaty vaccine reduced infections tenfold and Covid-19 deaths by 90%.
Additionally, UK Health Security Agency data showed that booster doses given after six months increased protection from hospitalisation to 88% from 55%, using a mix of mRNA vaccines and the viral-vectored AstraZeneca vaccine, with boosters of only mRNA.
According to the government, almost 13 crore persons above the age of 60 are yet to get the first Covid-19 jab. Most immunisation experts are concerned that the decision about the booster doses have not been taken in a timely manner and the government’s decision appears to be reactionary in the absence of any robust evidence on what type of vaccines are to be used for booster doses.
Health experts, who did not want to be named, said the actions of the government resembled the attempt to install fire-safety equipment in a building while it was already on fire. The government should have discussed the booster months ago, and not while the country is in the middle of the third wave, they said.
Senior public health researcher at the George Institute of Global Health, Dr Oommen John, explained that at the current rates of transmission, a large number of persons eligible for booster doses would be excluded from benefits of the booster dose as the current guidelines suggest that they can only be given the booster dose 90 days after infection.
“By the time the government arranges booster doses for everyone, a large segment of the population will already be infected. In essence, a large population who would be experiencing breakthrough infection will not be able to take the booster despite the good intentions of providing boosters to everyone,” he said.