A record number of suspected mumps cases have been reported in Wales over the past three months, it has been revealed.
The alarming spike in cases, which has been repeated in other parts of the country, has sparked calls from health experts for parents to make sure their children get all necessary vaccinations.
According to latest figures, there were 396 suspected cases of mumps reported in Wales in July, August and September - more than treble the 111 cases reported over the same period in 2018.
It is the highest number of suspected cases for this period since comparable records began in 2010.
Since the start of the year, Wales has seen 1,093 suspected cases of mumps, a huge leap from just 355 in 2018.
Mumps is a contagious viral infection which causes painful swelling to the side of the face under the ears (parotid glands).
Symptoms include headaches, joint pain and a high temperature, which may develop a few days before the swelling begins. There may also be swelling around the ovaries in girls or testes in boys after puberty.
Most cases of mumps are mild and around a third of people infected with the virus develop no symptoms, but when complications occur they can be serious. In fact, it is the commonest cause of viral meningitis.
Dr Mary Ramsay, head of immunisation at Public Health England (PHE) which compiles the data for Wales and England, said: "Although it is normal to see mumps outbreaks in universities every few years, we are seeing a significant number of cases, the highest quarterly figure since 2009.
"These figures clearly demonstrate the need for sustained high vaccination rates. We're urging parents and their children, no matter how old they are, to check they've had two doses of the measles, mumps, and rubella (MMR) vaccine.
"Vaccines are there to stop the spread of disease and save lives. It's never too late to protect yourself and others."
According to Public Health Wales' vaccine uptake report, 94.5% of children were given the MMR jab in 2018-19 compared to 94.7% in the previous financial year. The target is 95%.
Dr Christopher Williams, consultant epidemiologist at Public Health Wales, said: "There has been an increase in the number of suspected cases of mumps notified to Public Health Wales so far this year. A similar increase has been seen in other areas of the UK.
"There is evidence that mumps cases increase periodically every few years, due to changes in population susceptibility over time.
"The age group most affected are those aged 18-25 years, who account for over a third of the cases so far in 2019. Young adults should ensure that they are immunised, and follow guidance issued by educational institutions.
"Vaccination with the MMR vaccine, which also protects against measles and rubella, remains the best way of preventing mumps infections.
"We urge anyone born after 1970, who has not received a full two-dose course of MMR vaccination to get in touch with their GP to arrange to be vaccinated."
Meanwhile, the statistics proved much more encouraging when it came to suspected cases of the highly infectious viral illness, measles, in Wales.
There were 37 suspected cases of measles recorded since the start of the year, down from 103 in 2018.
