Study: Benefits of Vaccines Outweigh Dangers

Aug. 29 -- Back to school time often means a trip to the pediatrician for vaccinations. And as the number of vaccines being given increases so does the number of parents concerned about possible side effects.

A new study aims to put those fears to rest.

According to an article published today in the New England Journal of Medicine, children who receive the whole-cell pertussis (DTP) vaccine, or measles, mumps and rubella (MMR) vaccine, may be at an increased risk of developing rare seizures brought on by a high fever.

However, the numbers are low, 6 to 9 seizures per 100,000 children are attributed to the DTP vaccine, and 25 to 34 per 100,000 children to the MMR vaccine. Both vaccines are given in a series during the infant years, and once more before children start school.

Researchers from University of Washington and the Kaiser Vaccine Study, examined the medical records of nearly 700,000 children. The DTP vaccine was only associated with an increased risk of seizure on the day it was administered. The MMR vaccine was associated with an increased risk of seizures eight-to-14 days after vaccination.

'Scary' Seizures Not Harmful

The researchers are also quick to point out that although the seizures may be "scary" at the time for both children and parents, no long-term neurological damage is done.

"A very important part of this study is the observation that these events, although the seizures did occur, were not associated with any long-term problems in these children," says Dr. Steven Black, co-director of the Kaiser Vaccine Study and co-author of the New England Journal study.

Black also points out that the study examined the effects associated with the DTP vaccine, which has long been the subject of debate.

"In the past, there has been a considerable amount of controversy surrounding the safety and side effects of vaccines, especially the DTP," says Dr. Bob Davis, second author of the study and professor of pediatrics and epidemiology at the University of Washington. DTP is rarely used anymore because it caused fever in a lot more children. (The study began in the early 1990s when it was the primary vaccine give to protect against the disease.)