Over the past few years, despite scientific uncertainties, French courts have awarded compensation to sufferers of multiple sclerosis (MS) which occurred following vaccination against hepatitis B. These legal decisions have aroused fierce criticism in the medical world. Both a judgment given on 25 May 2004 by the Court of Cassation and a new publication in the journal Neurology have encouraged us to look once more at this controversial issue. French judges began compensating patients with MS at the end of the 1990s. One of the first judgments was given in 2001 by the Court of Appeal of Versailles when a pharmaceutical laboratory was held liable for the onset of MS following vaccination against hepatitis B. On appeal, the Court of Cassation overturned the judgment in September 2003, finding that the Court of Appeal judges had based their decision on a hypothetical causal link. However, the only reason why the Court of Appeal judgment was quashed was the contradictory evidence on which the judges had based their presumptions. Several of the judgments given since that date seem to confirm this hypothesis. On 25 May 2004, the 2nd civil law chamber recognized that MS which occurs following a vaccination against hepatitis B (a vaccination carried out for work-related purposes) could be considered as an accident at work, without questioning the possible causal link between the illness and the vaccine. This jurisprudence in the matter of hepatitis B vaccination shows the need for great care in expert practice. Effectively, when confronted with drug related imputability, the expert usually bases his reasoning on three points: the causal role of the generating factor, the chronology and other causes of damage. In terms of MS, all these factors are modified. More than ever, an expert must, in terms of imputability, be objective, prudent and clear in his conclusions.
Circulating Tfh cell and subsets distribution are associated with low‐responsiveness to hepatitis B vaccination
