The US Supreme Court has begun considering how much liability vaccine makers have if the side effects of their products are believed to have injured or killed someone. The case was brought against Wyeth (now merged with Pfizer of New York) by parents of Hannah Bruesewitz, who in 1992 began suffering seizures and developmental problems after being given the combined Corynebacterium diphtheriae toxoid/Clostridium tetani toxoid/polio (DTP) vaccine against diphtheria, tetanus and pertussis (whooping cough). A few years later, DTP was removed from the market and replaced by a vaccine with fewer side effects. The Bruesewitzes believed their daughter's injuries were avoidable because Wyeth should have put a product with fewer side effects on the market earlier.

What is most notable about the Bruesewitz v. Wyeth case, which was argued on October 12 in Washington, DC, is that many in the US drug industry had believed that the issue had been completely resolved with the adoption in 1986 of the National Childhood Vaccine Injury Act. The act set up a Vaccine Court to adjudicate claims of injury on a no-fault basis and pay successful claimants with money generated from a tax on vaccines. The Vaccine Act was put into effect because of a fear at the time that lawsuits claiming 'design defects' would force companies to stop making vaccines. Accordingly, the act says suits cannot be filed against manufacturers “if the injury or death resulted from side effects that were unavoidable, even though the vaccine was properly prepared and was accompanied by proper directions and warnings.”

There is a back door to the law that allows families to go to a federal court if they lose in Vaccine Court or they don't like the amount of its judgment. However, those suits are governed by the Vaccine Act, too.

But neither the Vaccine Court nor a lower US federal court accepted the Bruesewitzes' argument that their daughter's injuries could have been avoided by the manufacturer. However, the justices found the wording in the Act, and especially its use of the word “unavoidable” quite confused. Justice Stephen Breyer remarked “it's pretty hard to say the word unavoidable means avoidable.” A final judgment is expected in early spring of 2011.