January 11, 1887

Rabies vaccine

Jacques-Joseph Grancher defends Pasteur’s post-exposure rabies method at the Académie de Médecine

Pasteur was not in the room when his method faced one of its most dangerous challenges. The physician who gave the injections had to defend it for him.

An adversarial session in Paris

At a session of the Académie de Médecine in Paris on 11 January 1887, the physician Jacques-Joseph Grancher defended the safety and apparent effectiveness of Louis Pasteur's post-exposure rabies inoculations against Michel Peter's allegations that the method was dangerous and had caused deaths.

Pasteur was absent. The challenge centred on the recent death of a treated child, Jules Rouyer; Paul Brouardel attributed that death to uremic illness rather than rabies, and Peter disputed the interpretation.

Statistics under pressure

Grancher combined outcome statistics with clinical argument, emphasising the low observed mortality while contending that failures could reflect therapeutic risk, individual variation or predisposition rather than vaccine-induced rabies.

His headline count that day was provisional: 1,956 French and Algerian patients, cut to 1,929 in the finalised table once incomplete treatments were removed. Fuller contemporary follow-up through 31 December 1886 recorded 2,682 treated and 31 deaths, a mortality of 1.15%.

Neither an endorsement nor a cure

This was not a ceremonial endorsement by a united profession but a contested debate over safety, diagnosis, deaths after treatment and incomplete evidence. It did not end that evening: on 18 January Grancher answered accusations about undisclosed failures and promised detailed monthly statistics, and on 24 January Vulpian presented a fuller set of results.

The method was prevention after a bite, not a cure for established, symptomatic rabies. Pasteur was not a physician and did not perform the human injections; Grancher did, under medical responsibility.

A modern historical study concludes that autopsy evidence in one fatal case was suppressed.

Sources

Researched 24 Aug 2026 5 sources not yet audited

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What the sources leave uncertain

The date and occurrence of the Academy session are well documented. The uncertainty concerns the medical evidence presented: patient classifications were revised, diagnoses of rabies exposure were not uniformly secure, and historians have identified apparent suppression or selective presentation of autopsy evidence in the Rouyer case.
Contemporaries usually called this a preventive method after a bite. Calling it a treatment must not imply that it cured established, symptomatic rabies.