New Delhi, March 22: India has decided to extend the interval between doses of Covishield vaccines from four to eight to four to eight weeks, the Health Ministry said on Monday.

The Ministry said that protection is enhanced if the second dose of Covishield is administered between 6-8 weeks, but not later than stipulated period of 8 weeks keeping the existing scientific evidence in view.

The Centre has written to states and union territories to increase the interval between two doses of Covishield based on NTAGI and NEGVAC Recommendation.

However, for the indigenously produced Covid-19 vaccine, Covaxin, it decided to continue with the existing interval of 4-6 weeks.

In view of the emerging scientific evidence, the interval between two doses of Covishield, was revisited by National Technical Advisory Group on Immunization (NTAGI) and National Expert Group on Vaccine Administration for Covid-19 (NEGVAC) in its 20th meeting.

During this meeting the recommendation has been revised to provide the second dose of Covishield at 4-8 weeks' interval after the 1st dose, instead of earlier practiced interval of 4-6 weeks.

"This decision of revised time interval between two doses is applicable ONLY to Covishield and NOT to Covaxin vaccine," the Health Ministry said.

In a letter written by the Union Health Secretary Rajesh Bhushan to the Chief Secretaries of States and UTs today, he has noted that the Ministry has accepted the recommendations of NTAGI and NEGVAC and has thereafter advised the states and UTs to ensure the administration of second dose of Covishield to beneficiaries within this stipulated time interval of 4-8 weeks after 1st dose.

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 amongst programme managers, vaccinators and recipients of Covishield vaccine and ensure adherence of the revised dosing interval.