The measles vaccine may trigger ulcerative colitis and Crohn's disease, both bowel conditions, in adulthood.

Researchers at the Royal Free Hospital in London have found that vaccinated people were three times as likely to go on and develop one of the conditions as were those who caught measles naturally. Vaccinated people were also 2.5 times more likely to develop ulcerative colitis.

Their findings were based on a study of 3,500 who had the vaccine in 1964, with 11,000 people born in 1958 who were not vaccinated.

Risks of developing one of the conditions also increased, the younger the person was when vaccinated. Babies of 18 months were found to be more vulnerable than if they had had the vaccination when they were four or five.

The Department of Health, responsible for the measles campaign last autumn, has refuted claims of a link (The Lancet, April 29, 1995).

Effects of the diphtheria vaccine seem to wear off in adulthood, researchers have discovered. This means that booster shots will need to be given if the "herd immunity" concept is to hold up.

The Central Public Health Laboratory in London has discovered that a quarter of blood donors aged between 20 and 29 had insufficient immunity, whereas this doubled among the 50 to 59 age group.

All of this is a blow to the World Health Organization, which had designated 1995 as the year when diphtheria was to be eliminated in Europe (The Lancet, April 15, 1995).