‘Need for third booster based upon conjecture’

More data is needed to establish if a third anti-Covid-19 booster dose will more effectively help in fighting the surge in infections in the country as currently its requirement has been based more upon conjecture, health experts said.

Pfizer and Moderna recently announced that people who have received both doses of the PfizerBioNTech or Moderna coronavirus vaccines will probably need a booster shot this year and might need an annual shot thereafter.

Earlier this month, an expert panel of the Drugs Controller General of India (DCGI)had permitted Bharat Biotech to give a third dose of its Covid-19 vaccine Covaxin to a few volunteers in its clinical trials.

Currently, people eligible for inoculation in the country are being administered Serum Institute of India’s Covishield and Covaxin. Both vaccines are being given in two doses in a gap of up to eight weeks.

Bharat Biotech has proposed a booster dose after six months of the second dose.

Experts said the third booster dose needs more studies to determine if it will help in fighting infections more effectively.

Samiran Panda, Director of the ICMR National AIDS Research Institute, said if the companies are deciding on giving a third booster dose after two doses then it should be based upon data on immunological memory.

This means that after two doses what is the status of antibody concentration and after how long it comes below a level after which one needs the third booster dose, he said.