Sammy Sosa, a star baseball player for the Chicago Cubs, donated money last month to set up a clinic in his home country of the Dominican Republic. The clinic will vaccinate over 50,000 children a year. Having grown up in the abject poverty of the small Caribbean country, it seems that Sosa has a much better understanding of the value of immunization than some Congressional Republicans. The latter have held a series of hearings over the past few months to investigate vaccine safety and are perilously close to triggering public rejection of childhood immunization protocols.

The hearings, entitled "Vaccines: Finding the Balance Between Public Safety and Personal Choice," were spurred by parents who believe their children were harmed by routine immunizations, and by military personnel concerned about the safety of anthrax vaccines they have been ordered to receive.

Two subcommittees of the Committee on Government Reform held hearings on vaccine adverse reactions in May and the full committee, chaired by Congressman Dan Burton (R-IN), took up the issue on August 3rd. Burton is a proponent of alternative medicine who believes that two of his grandchildren have suffered serious adverse effects from hepatitis B vaccination.

Dan Burton

The hearings and their attendant publicity appear to have become increasingly dominated by political concerns and special interests, at the expense of sound science. Aside from Surgeon General David Satcher, and Samuel Katz, who represented the American Academy of Pediatrics and the Infectious Diseases Society of America, the only witnesses were parents who claim their children were injured by vaccines, and outspoken critics of mandatory vaccination.

Safety fears have been heightened by the news that the first vaccine designed to prevent rotavirus infection was suspended only 11 months after it was approved by the US Food and Drug Administration (FDA), following 20 reported cases of intusussception in infants. Data on the potential link between the vaccine and intusussception, a type of bowel obstruction, are expected to be released within a few months.

Public health experts in the US now worry that the safety debate could have disastrous consequences, such as those seen in France, where officials suspended hepatitis B immunization in the face of public pressure (Nature Med. 4, 1217; 1998), and in the UK, where parents refused the combination measles– mumps–rubella vaccine for their children following an autism scare (Nature Med. 5, 478; 1998).

In addition to the alternative healthcare and herbal supplement industry, Katz explains that "there's a whole other element which has allied itself to the cause and that is the more libertarian approach of 'why are our children required to have these vaccines, shouldn't it be freedom of choice?'" Some opponents of mandatory vaccination also claim that the pharmaceutical industry exerts undue influence over the Centers for Disease Control and Prevention (CDC) and the FDA, an issue that the committee is investigating.

Among those asserting that the CDC has a conflict of interest is Bart Classen, a physician and president and sole employee of Classen Immunotherapies, Baltimore, MD. At the May hearings, Classen testified that CDC data supports a causal link between the timing of hepatitis B vaccination and Type I diabetes. "No one's disputing the data. What's controversial is how the public health service is trying to deny it all," says Classen.

The CDC takes a different view. In a one-page report containing the data CDC researchers concluded that the possibility of such a link "cannot be ruled out and will require larger more detailed studies," (Pharmacoepidemiology and Drug Safety 6, S60; 1998), suggesting that although the data may not be in dispute, their interpretation clearly is. Classen owns patents on several vaccine-testing protocols which would likely be required if legislators are persuaded to accept his interpretation of the study.

Although no specific legislation has been proposed, committee staffers say that industrial procedures for vaccine testing and the possible removal of limits on vaccine manufacturers' civil injury liability are also key issues of evaluation.