Second dose of Covishield to be given after 6 to 8 weeks, says Health Ministry

On Sunday, in a letter to States and Union Territories, the Centre has directed the time between two Covishield vaccine doses should be increased from 28 days to six to eight weeks for better outcomes.

In a statement the Government said, "The Union Health Secretary has urged the states and UTs to instruct the concerned officials accordingly to undertake necessary steps to widely disseminate the message of revised dosing interval among programme managers, vaccinators and recipients of Covishield vaccine."

The amendedgap only extends to Serum Institute of India's Covishield, an Oxford AstraZeneca vaccine, and not to Bharat Biotech's Covaxin, according to the Centre's letter.

In a study published in the British medical journal Lancet, a 12-week or three-month gapbetween the first and second doses offers vaccine efficacy of 81.3 percentwhich way higher than the 55.1 percent efficacy in a gap of less than six weeks.

The Centre’s letter read, "In view of the emerging scientific evidence, the interval between two doses of a specific COVID-19 vaccine, Covishield, has been revisited by the National Technical Advisory Group on Immunization (NTAGI) and subsequently by National Expert Group on Vaccine Administration for COVID-19,"it further said, “During this meeting the recommendation has been revised to provide 2nd dose of Covishield at 4-8 weeks’ interval after the 1st dose, instead of earlier practiced interval of 4-6 weeks.”

The decision to expand the period coincides with the World Health Organization's (WHO) recommendation that the two doses of AstraZeneca vaccine be administered eight to 12 weeks apart.

The order is being issued in the midst of the second round of national vaccinations, which are being administered to citizens over the age of 60 and those over 45 who have other illnesses.