The anti-venereal trials at the Hospital General de San Andrés (Mexico City, 1790-1791)
An itinerant healer from Pátzcuaro brought a plant remedy for venereal disease to the archbishop of Mexico in July 1790, and instead of being dismissed or licensed on the spot he was given wards. Sixty-odd patients were treated to his instructions, in stages, with other medicines withheld, under the Protomedicato of New Spain — and a hospital physician who thought the whole thing a fraud wrote a long report saying so, which is why the trial's failures can still be read today.
Why this wins its question: Ask any current source about Balmis and you get the vaccine expedition; ask about drug testing before the nineteenth century and you get James Lind. Neither answer contains this: a staged, controlled, months-long therapeutic trial run inside a colonial Mexican hospital in 1790 under the royal medical tribunal, with a written dissenting report by the ward's own chief physician preserved in Madrid. This object binds both halves — the trial apparatus and the fraud it failed to catch — to the peer-reviewed study that reconstructed them from that dissenting manuscript, and marks the Balmis reassessment as the contested claim it is.
Claims
Every assertion below is bound to registered sources and carries its own confidence. Weight them; do not treat the page as uniformly authoritative.
The trial began with an unlicensed practitioner being taken seriously. In July 1790 Nicolás Viana, an itinerant healer from Pátzcuaro in Michoacán, presented a herbal remedy for venereal disease to Archbishop Alonso Núñez de Haro y Peralta, director of the Hospital General de San Andrés in Mexico City, claiming to have cured thousands of venereal patients over thirty years with a formula based chiefly on begonia and maguey, and offering it as faster, cheaper and less intrusive than the mercurial treatments then standard.
What followed was a staged hospital trial, not an endorsement. An initial stage treated twenty male and twelve female patients for one month according to Viana's instructions, without medical intervention or alternative medicines; the results being inconclusive, a second stage of forty men and twenty women ran for two months on the same terms.
The evaluating body was the licensing authority itself. The trials were overseen by the Protomedicato, the royal tribunal regulating medical practice in New Spain — three physicians, two of them holders of university chairs and one appointed by the viceroy — whose president, José Ignacio García Jove, also served as a physician in San Andrés's medical wards, so the tribunal was judging a therapy inside a hospital where its own president practised.
The authorities concluded that the "Beato method" was a specific for venereal disease and administered it in place of mercury. The Valencian surgeon Francisco Xavier de Balmis, who championed the cure, travelled to Madrid in 1792 with plant samples for further trials and published his Demostración de las eficaces virtudes nuevamente descubiertas in 1794; it was translated into Italian and published at Rome in 1795.
The most valuable document the episode produced is the hostile one. Daniel O'Sullivan, an Irish physician-surgeon educated at Toulouse, Montpellier and Edinburgh and serving as chief physician of the venereal department at San Andrés, wrote a Relación histórico-crítica — commissioned by the Royal Academy of Medicine in Madrid, never endorsed by the Mexican authorities — that describes the trials as theatre: "All the patients entered singing and dancing… This farce was much applauded by the Beato's supporters but any philanthropist… could not help but be filled with indignation."
The costs O'Sullivan records belong on the same page as the method. He describes practitioners kept silent by fear, protomédicos assessing patients superficially and dismissing symptoms as trivial, at least one soldier dead of tumours that progressed under the treatment with blame shifted to the opposing physicians, and — the substantive harm — the prohibition of any form of mercury in order to promote the chosen method, which removed the one treatment of the period with a real effect on syphilis.
Dissent was rewarded abroad and punished at home. O'Sullivan was made a corresponding member of the Royal Academy of Medicine in October 1793 on the strength of his critical analysis, and claimed that his opposition brought open persecution and eventual dismissal; the article records that it is unclear why little or no action was taken against the continued promotion of the cure.
The man who promoted the discredited remedy is the man the corpus otherwise celebrates. Balmis was granted the title of Honorary Surgeon of the King's Bedchamber in 1795 and went on to direct the Royal Philanthropic Vaccine Expedition of 1803-1813. The article's argument is precisely that institutional history privileges the later success and passes over the earlier bad medicine, corruption and lives lost — a reading of Balmis that is revisionist and contested, and is stated here as this author's finding.