LONDON -- England and Wales are experiencing the most serious outbreak of mumps in nearly a decade, largely because young adults missed out on the MMR (mumps, measles and rubella) program which began in 1988. The outbreak raises questions about the babies who are currently missing out on the combined vaccine.
Figures from the Health Protection Agency (HPA) show that confirmed cases of mumps more than tripled last year, from 497 in 2002 to 1529 cases in 2003. The trend is continuing to rise, with 578 cases reported in England and Wales during the first quarter of 2004.
The HPA emphasizes that these cases are not linked to the recent drop in take-up of the MMR vaccine caused by parents fears that it may be linked to autism. But Dr. Vivienne Nathanson, head of science and ethics at the British Medical Association, says the outbreak poses a worrying public health risk, since the recent fall in numbers of infants immunised against MMR puts those children directly at risk of infection from older brothers and sisters. The MMR vaccine is key in the fight to stop dangerous and debilitating illnesses infecting and re-infecting the community.
Dr. Mary Ramsay of the HPAs Immunization Department says the mumps outbreak affects mainly young people born before 1990. They were offered the single measles vaccine and later had the combined measles and rubella vaccine as part of the 1994 school vaccination campaign. The combined MMR jab was not introduced until 1996.
Only a few will have received MMR vaccine and therefore any protection at all against mumps, Ramsay points out. Hardly any will have received a second dose of MMR, which is necessary to achieve good levels of protection. The increase in mumps underlines the importance of children having both doses of MMR, so that they have good protection against all three diseases.
Before vaccination was introduced, there were an estimated 100,000 mumps cases every year. The current outbreak has led to guidelines being sent to health professionals to encourage young adults, particularly school leavers and university students, to have MMR shots now.
Mumps causes fever, headache and painful swollen glands and is easily spread through coughs and sneezes. It can also cause viral meningitis and permanent deafness. More rarely, it can cause inflammation of the pancreas, ovaries and testicles, causing sterility in males and infertility in females.
Fiona Smith, childrens nursing adviser at the Royal College of Nursing, says many parents concerned at the alleged link between MMR and autism either decided not to allow their babies to be vaccinated at all, or did not go back for the second MMR shot.
This mumps outbreak shows that the children who have missed out in recent years may be at risk of all three diseases. You need to have around 70 percent of children vaccinated to achieve herd immunity. There may be some areas in the country where uptake was low and unvaccinated children are at risk.
Experts insist that there is no credible scientific evidence showing an association between MMR and autism. But a new study by researchers at Bristol University is to examine the vaccination issue and the impact of environmental factors in the development of autism.
Source: Health Protection Agency