If you're going to give your child with measles, mumps, rubella jab, don't do it when he or she has a cold.
A study in Washington and Hawaii of group of toddlers with colds given the MMR jab found that one fifth failed to develop any measles antibody, compared to two per cent of well infants who were vaccine failures. "We conclude that infants with colds have a significant. . . failure rate associated with measles vaccine administration and that this may be the cause of some primary measles vaccines failures," said the report.