Secondary schools in Swansea and Neath Port Talbot will be targeted in another round of school MMR vaccinations this week.
Over 1,700 pupils will be offered the jab in 10 schools across the areas.
Health experts have urged parents of pupils who have had no MMR or who need a second jab to take advantage of the school clinics.
Measles is a horrible disease and the number of cases is still growing, with the latest figure standing at 765. Children and teenagers who are not protected with MMR have a very high risk of catching measles.
MMR is a simple and safe jab which will protect them during this serious measles outbreak. I would urge parents of unvaccinated or under-vaccinated children to sign the consent form so our nurses can give them an MMR jab in school.
– Sara Hayes, Director of Public Health at ABMU
Around 3,400 people turned out to receive the MMR vaccination in the latest round of clinics in South Wales over the weekend.
Health chiefs at Abertawe Bro Morgannwg University Health Board say 1,800 people were vaccinated at the area's four drop-in MMR clinics today – the highest number so far.
The full numbers are:
Princess of Wales Hospital: 727
Neath Port Talbot Hospital: 455
Morriston Hospital: 341
Singleton Hospital: 302
Many of the 1,825 given MMR jabs were older schoolchildren, teenagers and young adults - the target age group for vaccines.
I’m really pleased. We have seen a steady flow of people throughout the day; and I’m particularly delighted to see a higher number of older children and teenagers come through the door, as they are our main target group.
I’m also impressed with how smoothly the clinics are running. Our staff are working very efficiently and for most of the day there have been very few queues. After the initial rush, many people have arrived and either been seen straight away or waited just 10 or 15 minutes.
We can’t bring this outbreak to an end unless the parents of unvaccinated children either arrange vaccination with their GP, call into one of the weekend drop-in sessions or ensure that if their child attends a school where vaccinations are being offered, they have signed a consent form for them to be vaccinated.
As children return to school after the Easter holidays, the opportunities for measles to spread increase. Now is the time to vaccinate your children.
– Dr Marion Lyons, Director of Health Protection, Public Health Wales
Wales' Health Minister says he "remains concerned" about the measles outbreak, and anticipates that the number of cases "will continue to rise over the coming weeks."
In a written statement, Mark Drakeford reiterated the calls of public health officials for as many people as possible to have MMR vaccinations.
Abertawe Bro Morgannwg Health Board begins vaccination clinics in schools in Swansea tomorrow, and Mr Drakeford said other health boards will also be offering catch-up clinics targeting schools with low vaccine uptake.
He said: "The Welsh Government, Public Health Wales and the Health Boards will continue to take all necessary and appropriate measures to reduce the impact of the outbreak as far as possible."
The latest figures on the number of cases in the outbreak are due later today. Last week they reached 693.