More than 80,000 children aged between 12 and 15 have booked to receive their COVID-19 vaccinations in England.
Some 2.5 million letters will be sent out this week inviting parents to book a jab for their child through the national booking service.
And more than 100 existing vaccination centres have opened their doors for this age group.
While vaccines have been available to 12 to 15-year-olds in England since 20 September, the rollout has so far mostly taken place in schools.
But since Friday, parents and guardians have been able to book jabs online at sites for their 12 to 15-year-old children.
More than 80,000 children in that age group had booked their vaccine by Tuesday morning – with nearly 33,000 bookings made on Monday alone.
Dr Nikki Kanani, GP and deputy lead for the NHS vaccine programme, said: “The NHS is making it as easy as possible for parents to get their child protected this half-term, with tens of thousands of young people booking in online with their families so far.
“It’s really important that we keep that momentum going if we want to ensure children get to stay in the classroom with their classmates this winter so if you’re thinking about getting your child vaccinated, I would encourage you to head online and look at the information.”
Health Secretary Sajid Javid said: “Our historic vaccine rollout continues to go from strength to strength, and more than 80,000 young people aged 12 to 15 have now booked in to receive their jab.
“The vaccines are available to young people through a tried and tested school immunisation programme and parents or guardians can book a jab at local vaccination sites, making it easier and more convenient for everyone to secure this important protection ahead of the winter months.
“The vaccines are safe and help keep children in the classroom so they can learn and spend time with their friends.”
Vaccines minister Maggie Throup said: “This fantastic progress means that we are strengthening our wall of defence against the virus and I urge as many people as possible to come forward for a jab as soon as they can.”
