Pupils at Devizes School in Wiltshire have been vaccinated this morning after a measles outbreak.
Two cases were confirmed and a number of others are suspected at the school.
Immunisation against measles, mumps and rubella is also open to pupils' families from 3pm on Wednesday.
There will be a further session on Friday.
A measles vaccination programme in underway in Wiltshire after cases were confirmed at one of the county's schools.
Pupils at Devizes School, aged between 10 and 16, are being offered MMR vaccinations tomorrow and on Friday. They'll also be made available to brothers and sisters of pupils and to members of staff.
Wiltshire Public Health officials say it is important that children receive two doses of the vaccine, so some may need the top-up.
The news follows a major outbreak in the Swansea area where more than 1,030 cases have been reported.