India extended Covid vaccinations to teens aged 15-18 on Monday, after officials tightened restrictions in big cities to avoid a repeat of last year's devastating outbreak.
More than 200,000 people around India died in a huge spring virus wave that overwhelmed hospitals and crematoriums.
Health workers have since administered more than 1.4 billion vaccine doses but less than half of India's population is fully inoculated, according to government data.
Hundreds of teenagers patiently queued with their parents on Monday morning outside a school turned into a makeshift medical centre in the capital New Delhi.
"It's really great to have your first vaccine," said 16-year-old Soumadeep, after receiving his first dose of the Indian-made Covaxin.
"It's like a new year gift for the children."
Officials have fretted over the arrival of the Omicron coronavirus variant and a sudden rise in daily infections, with some of India's biggest urban centres imposing fresh restrictions last week.
New Delhi and tech hub Bangalore are under overnight curfews from 10 pm each evening, with bars and restaurants in both cities ordered to operate at half capacity.
Mumbai, India's commercial capital, has barred public gatherings of more than four people from 9 pm to 6 am and restricted wedding ceremonies to 50 guests.
- 'Safeguard the kids' -
Last year's Delta variant wave in India struck after one of the world's biggest religious gatherings, the Kumbh Mela, which attracted around 25 million Hindu pilgrims.
That festival, along with large state election rallies, was blamed by experts for fuelling the surge.
Despite a record rise in global infections, the Omicron outbreak has seen a less dramatic increase in hospital admissions, fuelling hopes the variant is less severe than Delta and other strains.
But the experience of last year's outbreak has left many worried for the weeks ahead.
"It's a concern -- the cases are on the rise," said Pushp Jain, whose son was queuing to receive his first dose in Delhi on Monday.
"The variant is mild. But obviously to safeguard the kids, we need to have the vaccination."
India has the world's second-highest number of cases, with nearly 35 million confirmed infections.
Its 481,000 known Covid deaths are the third-highest, behind the tolls in the United States and Brazil.
But under-reporting is widespread and some studies have estimated India's true toll could be up to 10 times higher.
India will begin rolling out booster vaccines for people aged over 60 from next Monday.