Health bosses are concerned about the number of children who may not be fully protected against measles.
Barnsley Council's public health team is concerned that children between the age of 10 and 16 may not have been fully vaccinated.
Barnsley has seen a good take up of the combined measles, mumps and rubella jab, with 94 per cent of children under five having the recommended two doses before their fifth birthday.
Over the last three years, there have only been six cases - all last year - and there have been no new cases in this latest outbreak.
Sharon Stoltz, acting director of public health for Barnsley, said measles can often be a very unpleasant illness.
"Even though Barnsley has a good uptake of MMR in children under five, we are concerned that older children may not have been fully vaccinated and are therefore not protected from the disease.
"We are particularly concerned about children aged between 10 and 16 years who are most at risk.
"Plans are being put in place to organise a catch up campaign for any children in this age group who are not fully vaccinated.
"Further information will be available on this in due course.”
