Mumbai - India began its vaccination drive for children aged 15 to 18 today. The country seeks to expand its inoculation effort to cover the world's largest adolescent population amid concerns that the Omicron variant will drive a new surge of infections.

Union Health Minister Mansukh Mandaviya advised states and UT's to provide separate vaccination centres, session sites, queues and different vaccination teams for the 15-18 year age group to avoid a mix-up.

The CoWIN app had already recorded over six lakh registrations till Sunday evening. The vaccine option for this age group would be indigenously-developed Bharat Biotech’s Covaxin. The states will have to adhere to guidelines issued by the Union Health Ministry on December 27.

Thousands of children, many accompanied by parents, queued up outside schools, medical centres and special health camps from early on Monday to secure their first dose of a vaccine.

Bharat Biotech's Covaxin is the only vaccine to be administered to children as of now. This is the only vaccine with emergency use listing for the 15-18 age group, the health ministry said last week.

Authorities on Monday reported 33,750 new COVID-19 cases and 123 deaths. The total number of cases of the fast-spreading Omicron variant detected in India was 1,700, the health ministry said.

The U.N. children's agency UNICEF estimates India has the largest population of adolescents in the world with about 253 million of them.

Several countries including the United States, Britain and South Korea have seen infections among children fuelling a rise in cases in recent weeks and have encouraged parents to get their children vaccinated.