In 1899, bubonic plague reached the port of Santos, and the São Paulo state government panicked. They needed anti-plague serum, and they needed it fast. A physician named Vital Brazil Mineiro da Campanha was dispatched to Santos with a microscope, culture media, and autopsy instruments. He set up a makeshift laboratory in the isolation hospital and confirmed the diagnosis. The state established a serum therapy laboratory at the Butantan Farm on the western outskirts of São Paulo, and on February 23, 1901, Vital Brazil became its first director. By June of that year, the first vials of anti-plague serum were ready. But Vital Brazil had broader ambitions. He recognized that snakebite killed far more Brazilians than plague ever would, and he became the first scientist to demonstrate that snake venoms display antigenic specificity -- meaning that a serum made from one species' venom would not neutralize another's. He developed monovalent antivenoms targeting specific species, a breakthrough that made effective treatment possible across the tropics.

Walk the grounds of Instituto Butantan today and you will find the serpentarium -- an open-air enclosure where pit vipers, coral snakes, and rattlesnakes bask in the subtropical sun. The institute maintains one of the world's most important collections of venomous animals: not just snakes but spiders, scorpions, and insects. Venom is extracted regularly and processed into antivenoms that are distributed free across Brazil's public health system. The institute also operates the Hospital Vital Brazil, a specialist facility offering free treatment for venomous bites and stings. For researchers, the venom is raw material for something more ambitious -- compounds being tested as treatments for diseases like leishmaniasis and Chagas disease. What kills in the forest heals in the laboratory. Butantan is Latin America's largest producer of immunobiologicals and biopharmaceuticals, manufacturing vaccines against tuberculosis, rabies, tetanus, and diphtheria, among others.

On May 15, 2010, an electrical fault sparked a fire in the building housing Butantan's natural history collection. The blaze destroyed approximately 85,000 preserved snake specimens and an estimated 450,000 spiders and scorpions -- one of the largest collections of venomous animals in the world, assembled over more than 90 years. Francisco Franco, the collection's curator, described the loss plainly: "All knowledge of Brazil was there -- 100 years of history." Specimens that represented decades of fieldwork across the Amazon, the Cerrado, and the Atlantic Forest were reduced to ash in hours. Some species had been cataloged nowhere else. The scientific community mourned what it called an irreplaceable loss to taxonomy and biodiversity research. Butantan rebuilt. New specimens were collected. New protocols were written. But the fire left a scar that no amount of rebuilding could fully heal -- a reminder that knowledge preserved in only one place is knowledge at risk.

When COVID-19 reached Brazil in 2020, Butantan's 119-year-old mission -- produce what the public health system needs, now -- kicked in again. The institute partnered with Chinese pharmaceutical company Sinovac to manufacture CoronaVac, an inactivated virus vaccine, at a new facility capable of producing up to a million doses per day. CoronaVac became the backbone of Brazil's early vaccination campaign. By 2022, the vaccine had been administered in 45 countries and accounted for roughly a quarter of all COVID-19 immunizations worldwide. Butantan had come full circle: founded to fight one epidemic, it helped fight the worst pandemic in a century. The farm on the outskirts of São Paulo where Vital Brazil set up his microscope in 1901 is now surrounded by city. The snakes still coil in their enclosures. The venom is still extracted, drop by careful drop. And the institute still operates on the principle its founder borrowed from the Pasteur Institute -- research, produce, sustain.