The Centre has told the Delhi High Court that experts are deliberating on the possible need and justification for booster doses of COVID-19 vaccines and currently there are no guidelines on it.

The Centre's stand before the high court assumes significance as the issue of whether to administer booster dose of COVID-19 vaccines has cropped up amid the new Omicron variant of coronavirus.

The affidavit was filed before a bench of justices Vipin Sanghi and Jasmeet Singh which is scheduled to hear during the day various issues relating to COVID-19 crisis in the national capital at the time of the second wave of the pandemic.

The Centre said that the National Technical Advisory Group on Immunization (NTAGI) and National Expert Group on Vaccine Administration for COVID-l9 (NEGVAC) are two expert bodies working in tandem to guide the National COVID-19 vaccination program.

While NTAGI examines the technical aspects like usage of different varieties of COVID vaccines, interval between vaccine doses, contraindications etc and recommend the same to NEGVAC which in turn provides overall guidance and recommendations on all aspects of COVID-19 vaccination to Ministry of Health and Family Welfare.

"The NTAGI and NEGVAC are deliberating and considering scientific evidences related to dose schedule of COVID-19 vaccines as well as the need and justification of booster doses.

"The current knowledge about duration of immunity offered by COVID-19 vaccines in India is limited and will clearly be known over a period of time only," the affidavit said.

The Centre said the epidemic of SARS-CoV-2 infection and the resulting disease has impacted India since 2020 as a new infectious disease, complete biological characteristics of which are unknown and under such circumstances the appropriateness or necessity of booster dose of COVID vaccine is yet to be decided.

"The current priority of National COVID- 19 Vaccination Program is to cover the entire eligible population with full vaccination (that is, two doses) and at present there are no guidelines regarding administration of booster doses from the two expert bodies," it said.

The Centre's affidavit was filed in pursuance to the court's November 25 order by which the government was asked to respond on the aspect of need for administration of booster dose of COVID-19 vaccines and the timeline within which the same is proposed to be rolled out on the Aarogya Setu application, if it is considered necessary.