Covid: ‘Booster call may hinge on immunity levels’

NEW DELHI: The decision to administer booster shots will depend on waning immunity and effectiveness of vaccine, say official sources, though India may have surplus Covid vaccines by the end of the year and several countries with high vaccination rates have already started administering them.

Most countries with mRNA vaccines have started giving booster shots. However, experts say mRNA jabs are essentially three dose vaccines.

However, going forward India may consider giving booster shots to select population who are immunocompromised or are highly vulnerable to infection.

In India, the National Technical Advisory Group on Immunisation has assessed the real-life data from sero prevalence studies. One of the findings are that extended gap of at least 12 weeks between two doses of Covishield - which accounts for around 88% Covid immunisation in the country- has resulted in a better immune response among majority of vaccinated Indians, subsiding any immediate requirement for booster shots. Bharat Biotech's Covaxin has also been found to be effective against Delta variant - which continues to be most prevalent.

Experts say the second wave in India has also helped people gain natural immunity.