In view of the emerging scientific evidence, the interval between two doses of a specific Covid-19 vaccine i.e. COVISHIELD, has been revisited by National Technical Advisory Group on Immunization (NTAGI) and subsequently by National Expert Group on Vaccine Administration for Covid-19 (NEGVAC) in its 20th meeting. During this meeting the recommendation has been revised to provide second dose of COVISHIELD at 4-8 weeks’ interval after the first 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.
In a letter written by the Union Health Secretary Rajesh Bhushan to the Chief Secretaries of States/UTs today, he has noted that the Union Ministry of Health and Family Welfare, has accepted the recommendations of NTAGI and NEGVAC and has thereafter advised the states and UTs to ensure the administration of the second dose of COVISHIELD to beneficiaries within this stipulated time interval of 4-8 weeks after the first dose.
Keeping the existing scientific evidence in view, it appears 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. 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 amongst programme managers, vaccinators and recipients of COVISHIELD vaccine and ensure adherence of the revised dosing interval.