A council in the Midlands is highlighting the importance of the MMR vaccination following a Measles Virus epidemic.
Derby City Council is urging parents who haven't already done so to get children vaccinated against the virus.
The majority of cases in the current outbreaks have been reported in unvaccinated school children and young adults.
– Ben Anderson, Consultant in Public Health for Derby City Council
We estimate that 4,000 – 5,000 children and young people between 10 and 20 years of age in Derby are not vaccinated against measles and so are not protected against the virus.
Measles is a highly infectious disease that spreads very easily and in some cases can cause serious complications and death.
Health officials have told ITV News Central they are bracing themselves for a potential outbreak of measles. Officials in Herefordshire fear the epidemic in Wales means an outbreak is 'on the doorstep'.
They say that so far this year they've already had the same number of cases as they had for the whole of last year. Charlotte Grant has been speaking to one family, who knows how frightening measles can be.
– ELIZABETH SHASSERE, HEREFORDSHIRE'S DIRECTOR OF PUBLIC HEALTH
"Measles is a highly infectious and potentially dangerous illness which spreads very easily particularly in schools.
It is crucial that children and young adults are fully immunised with the necessary two doses of MMR".
"The good news is that it is highly preventable when children are immunised with the MMR vaccine, but parents need to make sure their children receive two doses of the vaccine in order to be fully protected against measles.
We are seeing an increase in the number of cases as a direct result of parents not getting their children immunised."
Health professionals in Herefordshire are preparing for a measles outbreak after it's emerged that one in five children in the county are not fully immunised.
It follows a recent outbreak of the disease in South Wales. Parents are being urged to ensure their children have had two MMR jabs.