Parents often give their infants acetaminophen (Tylenol) after immunizations and booster shots. As it turns out, this may do more harm than good. The medication may actually weaken infants’ immune systems, according to research from the Czech Republic.

Acetaminophen is sometimes given to infants and small children following shots to prevent fever, a common reaction to vaccinations. This study examined the effects of acetaminophen on immune response after initial and booster vaccinations.

Two hundred twenty-six children from 10 different medical centers were randomly selected to receive three doses every six to eight hours for 24 hours after immunizations. Just 42 percent of these children experienced fevers (100.4 degrees F or above), compared to 66 percent of a control group of 233.

When it was time for booster shots, parents were asked to repeat the process. There was a lower incidence of fever in both groups—36 percent for those who took acetaminophen and 58 percent for those who did not.

Children who received acetaminophen , however, had fewer antibodies, indicating more susceptibility to disease. In the studied children, pneumonia, hepatitis B, whooping cough, polio, diphtheria and tetanus antibodies were fewer following vaccinations and boosters with acetaminophen use.

Antibodies are proteins in the immune system (immunoglobulins) that bind to harmful pathogens (viruses) to keep them away from healthy white blood cells. Without these antibodies, the body’s immune system is more susceptible to disease.

When vaccines fail to protect against diseases, the health of the entire community is at stake because viruses are more easily spread.

“This point has implications, especially for Haemophilus influenzae, for which higher and sustained antibody concentrations are needed (to reduce transmission),” says Dr. Robert T Chen of the Centers for Disease Control in Atlanta, “…and for pertussis, the bacterial vaccine-preventable disease that is least controlled.”

Although they’re not entirely sure why children taking acetaminophen had fewer antibodies, doctors plan to explore the issue further. They stress the importance of this information, and advise against unnecessary acetaminophen use.

“(A)dministration of antipyretic drugs at the time of vaccination should nevertheless no longer be routinely recommended without careful weighing of the expected benefits and risks,” wrote lead author Dr. Roman Pryula of the University of Defense in Hradec Kralove, Czech Republic.

The study appears in this month’s online issue of The Lancet.

A special vaccine court has ruled against three families who claimed that childhood vaccines caused their children’s autism. The judges in the Vaccine Court Omnibus Autism Proceedings concluded that the scientific evidence was overwhelmingly against the claim that vaccines can cause the developmental disorder.

The three families’ claims were seen as "test cases" for the more than 5,300 claims filed by parents claiming an association between early childhood vaccination and autism. The three families had claimed that the Measles-Mumps-Rubella (MMR) vaccine in combination with the mercury-containing preservative thimerosal that was formerly common in other childhood vaccines had cause their children’s autism symptoms. The court’s findings that the "that petitioners' theories of causation were speculative and unpersuasive" presumably deals a serious blow to the other pending cases. The court has yet to rule on three test cases in which the parents claim that thimerosal alone caused their child’s autism.

The proceedings were a part of the National Vaccine Injury Compensation Program set up in 2001 by the National Institutes of Health. The program allows people who believe they have been injured by vaccines to seek compensation from a $2.5 billion fund built up from a 75-cent-per-dose tax on vaccines. The no-fault payout system is meant to protect vaccine makers from costly lawsuits that could drive many out of the vaccine-making business.

In order to win compensation, complainants need only to provide evidence that vaccines sometimes cause that particular condition or injury and that it is more likely than not that the vaccines caused their injury.

The causes of autism remain a mystery. Despite the fact that a group of parents continue to claim that vaccines caused their child’s autism, no scientific research has yet provided a conclusive link between the two, and several large-scale studies provide strong evidence against such a link. Symptoms of autism tend to appear in early childhood, around the same time that vaccinations are given. Childhood vaccines are associated with some serious side effects including seizures and coma, but the risk of such events is incredibly low, far lower than the chance that an unvaccinated child will die of the disease their parents did not vaccinate them against.

If you have more questions about autism or you want to connect with other parents of autistic children, join the Healia Health Community for Autism. For more information on childhood vaccinations, including links to the CDC’s current immunization schedule, see the Healia Health Guide on Child Vaccines.

Photo: stevendepolo, Flickr, Creative Commons