Fourth vaccine will be an additional booster
The fourth COVID vaccine in India will be the second booster. Currently, in India two primary doses of COVID vaccine and one additional booster dose, also known as the precaution dose, is being administered.
While it seems that an additional booster dose will improve the immunity of the body and increase its resistance against the coronavirus, doctors and health experts are divided over its need and effectiveness among the Indian population in the current scenario.
"No need for fourth vaccine dose given current evidence"
Former head of epidemiology and communicable diseases at the Indian Council of Medical Research (ICMR), Dr Raman Gangakhedkar, on Tuesday said that there is no need for a fourth dose right now.
"Looking at the current evidence (of variants of the virus), it is not that big that there is any need for the fourth dose of the COVID-19 vaccine. There are many reasons for that. Currently, whatever vaccines are there, the virus escapes mutants over them which causes infections," news agency PTI reported the expert saying.
With booster dose, the immunity has been trained thrice
Dr Gangakhedkar explains that if a person has already taken the third dose of COVID vaccine that means his/ her T-cell immune response has been trained thrice.
"The core virus (of COVID) has not been changed so much that a new vaccine would be needed so try and have trust in our T-cell immune response," the former epidemiology head at ICMR explained.
Those who have taken booster dose showed a significant presence of neutralizing antibodies: Study
A study conducted by Karnataka government run Sri Jayadeva Institute of Cardiovascular Sciences and Research found that those who have received the booster dose of COVISHIELD vaccine showed a significant presence of neutralizing antibodies.
The study found that currently we do not need a fourth vaccine.
"The presence of neutralising antibodies indicates persistent antibody levels even at the end of 12 months following the booster dose," Dr CN Manjunath, director of the Bengaluru-headquartered institute said.
"Two-jab protection is not required right now"
A fourth shot of the COVID vaccine is unwarranted at the moment experts have said.
The need for a fourth shot is mostly fuelled by the COVID situation in China. On this, Satyajit Rath, adjunct faculty at the Indian Institute of Science Education and Research (IISER), Pune says, "There is no reason to expect that the Chinese situation, which is specifically shaped by the zero-Covid policies that the country implemented for almost three years, will predict anything in India."
"The Indian situation, with widespread actual infection in addition to vaccination, is quite different. And the Covid virus is after all spreading and therefore mutating in communities worldwide, not just in China, so new variants are emerging everywhere," he told PTI.
"Consider fourth dose for healthcare and frontline workers"
In December, Former Indian Medical Association president Dr. JA Jayalal had urged Union Health Minister Mansukh Mandaviya, in a meeting held against the backdrop of rising cases in China, Japan and other countries, to approve administering fourth COVID dose to healthcare and frontline workers.
Urging the government to provide augmented immunity to these workers in the form of an additional booster shot, Dr Jayalal had said that these people are more exposed to a larger number of coronaviruses than others. "Healthcare professionals are more exposed to a larger number of coronavirus infected patients resulting in cumulative accumulation of larger volume of viral load and repeated exposure to the virus which will trigger more infections among the healthcare community," PTI had quoted him saying.
A fourth dose might benefit immunocompromised patients
"The administration of 4th dose might be a considerable approach in vulnerable populations such as immunocompromised patients," says Dr Rohit Kumar Garg, Consultant, Department of Infectious Diseases, Amrita Hospital, Faridabad.
On a fourth vaccine, he says, "there is very limited data, to suggest any significant benefit against symptomatic infection and severe COVID-19, following administration of 4th dose of available COVID vaccines."
"Therefore, a more rational approach would be the use of bivalent COVID vaccines (based on old and new strains) for boosting immunity, similar to influenza vaccines (strains updated every season)," explains Dr Garg.
What a fourth COVID vaccine does?
The second booster or the fourth vaccine elicits a rapid immune response against the coronavirus.
Several studies have shown that the protection conferred by the first booster dose wanes after a few months due to which many countries including the US, the UK have introduced a fourth vaccine for older citizens.
However, limited data on the effectiveness of the fourth dose has a mixed response on whether it is necessary or not.
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