Covid-19: Studying need for booster shots, says Centre

India’s expert group on vaccinations, Negvac, has discussed the need for booster shots for Covid-19 but more scientific evidence is being studied for any decision, a top official said on Tuesday during the routine government briefing on Covid-19.

Several countries have begun administering a third shot of a coronavirus vaccine to people who may be more vulnerable or were first vaccinated more than six months ago, while more still have announced plans to do so from next month. Their decision prompted criticism from the World Health Organization (WHO), which called for a moratorium to allow for more doses to be sent to poorer countries where few have been vaccinated.

The need for boosters, however, has been underscored by the spread of the Delta variant, which has shown significantly more resistance to vaccines than others. “Negvac discussed this (booster shots) at the last meeting. We are watching the science for the need for such imperatives. We are studying this keenly. As you know WHO has called for a moratorium, while some countries have started,” said Niti Aayog member (Health) VK Paul.

“The science is still emerging in the area,” he added.

Paul also said the Delta variant was still leading to surge in cases in states showing high test positivity, and added that the increase in numbers is a cause for concern as the variant is highly transmissible with greater attack rate.

“We still have significant reasons to be concerned and significant reasons for us to remain vigilant, and significant reasons for us to enforce pandemic control measures in every possible way. As policy, government of India does not talk of mitigation; it talks of containment and that is the strategy that WHO also endorses. The so-called herd immunity that we have to reach, we will bring that through vaccination,” said Paul.

The officials at the briefing also gave details about another variant of concern, the Delta Plus, which has been detected in 86 samples in India, including 34 in Maharashtra. “We were doing two kinds of surveillance - to monitor variants of concern (coming from outside) and to monitor the impact of the Delta variant in the country. Today, we need to look for new mutants because they can reach anywhere any time,” said Dr SK Singh, director, National Centre for Disease Control (NCDC).

Kerala, one of the states with test positivity rates of over 10%, reported more than half of the total Covid-19 cases recorded in the country in the past seven days, and about 80-90% of the cases are a result of the highly transmissible Delta variant, Singh said. “The Delta variant almost took over the original variant as the main variant responsible for the new infections that were being reported,” said Singh.

At the beginning of the briefing, Union home ministry joint secretary Lav Aggarwal said 37 districts across nine states -- Kerala (11 districts) and Tamil Nadu (7 districts) included -- showed a rising trend in daily new Covid-19 cases over the past two weeks.

The reproduction number of the virus was more than 1 in five states -- Himachal Pradesh, Punjab, Gujarat, Madhya Pradesh and Uttar Pradesh, and equivalent to the nation average of 1 in three other states. A reproduction number of over 1 means the outbreak is expanding.

“The increasing trend of reproduction number in some states is cause of concern, although there is stabilisation in Covid-19 cases in the country,” said Aggarwal.

Experts said vaccination will help in curbing the disease transmission in the long run.

“We have to vaccinate ideally everyone to protect people from flare ups. Mutations are common in an RNA virus but the vaccines that we have are working against these mutations so people must come forward and get vaccinated,” said Dr GC Khilnani, former head, pulmonology and sleep medicine department, All India Institute of Medical Sciences, Delhi.

Paul also spoke on the issue of indemnity for vaccine makers and said the Centre was still deliberating upon the issue. “There are several dimensions to that arrangement when you want to access vaccines; and all those dimensions including the indemnity issue are being examined. Also, whatever decision you take with regards to one principal will be applicable to others. Therefore, wait for us to take the final decision,” he said.