7 November 2013 Last updated at 11:01 ET
The number of cases of measles in an outbreak in Neath and Swansea has more than doubled in the last two weeks.
Public Health Wales (PHW) renewed its call for parents to urgently get their children vaccinated to stop the disease spreading.
PHW said it was “very frustrated” with cases reaching 36 since early October.
The latest outbreak comes less than four months after Wales’ biggest measles outbreak ended – centred on the same area with 1,200 suspected cases.
The outbreak has affected four schools in the Abertawe Bro Morgannwg University Health Board (ABM) area.
We are very keen for this to be stopped before it can get any bigger ”
Dr Jorg Hoffmann Public Health Wales
“Parents and young people should not underestimate how serious measles can be and how quickly it can spread,” said Dr Jorg Hoffmann, consultant in communicable disease control for PHW.
“In a school setting, one child with measles sitting in a classroom for just one hour will lead to at least 70 per cent of other pupils who are not vaccinated catching measles.
“To prevent this outbreak from spreading even further, it’s crucial that unvaccinated children and young people receive two doses of MMR urgently and that those with symptoms do not attend school.”
PHW is working closely with ABM to bring the outbreak under control and where a sufficient number of children are unvaccinated in a school where there has been measles cases, school vaccination sessions will be arranged.
The Swansea area epidemic lasted eight months with suspected cases first reported in November 2012.
Measles outbreak hits Queensland
Thirty-five people have now contracted measles in Queensland in one of the worst outbreaks of the disease in Queensland’s recent history.
This year 30 of the 35 measles cases have emerged since August, with eight cases now confirmed at Woodford Correctional Centre.
Last year only four Queenslanders contracted measles.
Questions are being asked if the measles outbreak is linked to overcrowding in Queensland prisons.
The Department of Justice and Attorney General on Wednesday evening confirmed there were now 6432 prisoners in Queensland jails on November 6.
It is the first time in Queensland history prisoner numbers have been more than 6000.
The extra 832 prisoners include hundreds “doubling up” in cells at several prisons in the Ipswich area.
Measles cases in Wales triple in two weeks after experts warn that TWO MILLION children across the UK are at risk
Cases at four Welsh schools rise from 13 to 36 in two weeks
Around 30,000 children in the country have not been given MMR jab
Nearly 300,000 children from England have not been properly vaccinated
Around two million across the UK have no protection against disease
Uptake of vaccine dropped after discredited report by Andrew Wakefield which linked injection to autism
Measles cases in a region hit by an epidemic less than four months ago have tripled in the last fortnight.
There are now 36 cases of measles in south Wales, up from 13 just two weeks ago, as children from four schools have reported symptoms.
Doctors are urging parents to properly vaccinate their children after fears of a second epidemic in Swansea have spread.
Cases of measles at four schools in south Wales have tripled in two weeks after doctors warned that two million children across the UK have not had an MMR jab
Despite an uptake of MMR vaccinations during the outbreak which killed one and infected 1,200 last November, health chiefs warned that 30,000 children aged 10-18 are still unprotected.
In April Dr Helen Bedford, of University College London’s Institute of Child Health, warned that two million children across the UK are still unvaccinated, while figures showed 81 per cent of children in London had no protection from the disease.
Figured from Public Health England revealed that there are 300,000 children without an MMR jab that are being targetted by a new catchup campaign.
Public Health Wales (PHW) said it was ‘very frustrated’ that a significant number of young people had been given the first dose of an MMR vaccine, but had failed to follow it up with a booster shot within one month.
Parents are being urged to make sure their children have been given two MMR jabs to fully protect against the viral disease
It continued to stress that two doses of the vaccination was the only way to protect against the outbreak.