In the 15th and 16th centuries, the contact between Spaniards and American indigenous peoples had unexpected biological consequences. A new STD hailing from the Indias, the infamous syphilis, jumped to the Old World when crewmembers of Christopher Columbus, overeager to know the natives more intimately, did the deed with native women. In turn, diseases from the Old World like smallpox attacked the indigenous themselves, ravaging their unfamiliar organisms and causing a high death toll among the Mexicas that resisted Spanish assimilation (and also among the natives who allied with the Spaniards, but few modern people care about those anyway) during the Conquest of the Mexica Empire. The indigenous side of the exchange received the worst part, suffering an ultimately unknown but undoubtedly huge number of deaths across the whole continent, which has influenced some imaginative 21st century people into accusing the inevitably dastardly Spanish Empire of having engaged in biological warfare to depopulate their new lands, even although this would only destroy the purpose of their conquest in the first place by depriving them of subjects. The reality, however, could not be any more different.
Regardless of its devastation abroad, smallpox was still lethal in Europe up to the 18th century. At the time, the only known way to immunize people against the disease was variolation, a primitive and rather squicky procedure that involved extracting pus from infected pustules and injecting it into the subject, intending to inoculating him with an underfed form of the virus to build immunity, but this procedure was dangerous and often risked spreading the disease itself. Fortunately, an English doctor by the name of Edward Jenner made a great discovery in 1796: variolation worked much better when inoculating cowpox, a process we now call vaccination (from vaccina, Latin for something related to cows). However, this method still had a big problem, namely that the extracted fluid could not be kept fresh for more than ten days, and given that there was no cowpox in America, transporting there the demanded cure for smallpox proved quite a challenge. When continental Spain managed to get the vaccine in 1800, King Charles IV, who had lost his little daughter María Teresa to this disease six years before, decided they had to find a way to banish smallpox for good from the rest of his empire. The royal doctor who had translated the first vaccination instructional from French to Spanish, Dr. Francisco Javier de Balmis y Berenguer, was the man Charles IV had been waiting for.
In 1803, after a large smallpox outbreak had just exploded in the Indies, Charles IV gave his blessings to Balmis' proposition of a Real Expedición Filantrópica de la Vacuna, an expedition that would kickstart the spread of the vaccine over there, so the question now was how to carry it through the empire in which the sun never set. However, Balmis eventually came up with a revolutionary method that combined both vaccination and variolation to keep generating fresh fluid for months: he would gather unvaccinated people and, dividing them in pairs, he would inoculate the first pair with cowpox, and before they healed, he would use their pus to inoculate the second, and so on. Knowing the procedure was safe and worked well with children, he approached Isabel Zendal Gómez, chairwoman of an orphanage in La Coruña, and recruited 22 eight-year-old orphan kids to serve as the beginning of the aforementioned human chain. All aboard of the María Pita, a ship whose name remembered the Action Girl that helped defeat Sir Francis Drake and his obscure 1589 English Armada, the expedition sailed off to America to undertake a new conquest, this time that of a disease that would never torment again the subjects of the Hispanic Monarchy.
The Balmis Expedition, as it was more popularly called, carried first the cure to the Canarian Islands, and from there traveled to America. Upon arriving to the Viceroyalty of New Granada (modern Panama, Venezuela, Colombia and other countries), the expedition divided into two, with Balmis marching north towards New Spain (México) and Cuba while his second-in-command José Salvany y Lleopart went south to the Viceroyalty of Perú; Balmis would later travel to Philippines. The expedition found many difficulties through the road, as Balmis was denied more orphan children to continue the human chain in México and had to use black slaves, while Salvany fell ill of up to three other diseases and would die not much after, not to count superstitious indigenous that were wary of the whole thing, but the expedition endured all of this and kept on. Added to the efforts to Dr. Francisco Oller, Dr. Tomás Romay and Dr. Alejandro García de Arboleya, who had already introduced the vaccine in several points of the empire, and Dr. Santiago Granado y Navarro Calderón, who replaced Salvany in the expedition, they managed to immunize hundreds of thousands of people.
The expedition vaccinated whites, blacks, indigenous, mestizos, rich, poor and foreigners alike, which caused the interesting trivia fact that the Apache and Comanche tribes, which were part of the Viceroyalty of New Spain at the time, would end up receiving the vaccine against smallpox thirty years earlier than the humble class of their nearby British colonialists (something the Ohio natives would have surely used before the forces under Marshall Jeffery Amherst gifted them with blankets infected with smallpox). However, Balmis didn't limit its expedition to Spanish lands either. While he was doing the job in Philippines, knowing that China didn't have the vaccine yet, he convinced the Qing dynasty authorities to let him bring it to them, and so he did, leaving his place to Dr. Antonio Gutiérrez Robredo to finish things. Balmis reached the Portuguese city of Macau from the Philippines, shipwreck included, and spent some months vaccinating through China up to the province of Canton, doing the same in the British St. Helen islands in his way back to America. Granado would continue vaccinating through modern Argentine until 1812, while Isabel Zendal and the children, their mission finished, settled down in various places of the empire.
The expedition sent shockwaves through the medical world of the time, which saw it as a turning point that likely saved millions upon millions of lives. Balmis was received as a hero when he returned to Europe by way of Lisbon in 1806, and when Edward Jenner himself heard about its efforts, he stated, "I don't imagine the annals of history furnish an example of philanthropy so noble, so extensive as this." The event also served to give Jenner himself a boost of attention, and also gave Napoléon Bonaparte the idea to vaccinate his own troops in 1805, after which he awarded a medal to Jenner despite being at war with Britain at the time (he ignored Balmis, although that's hardly new for a Spaniard). In 1810, even with Napoleon having invaded Spain, Balmis would undertake a new expedition to the Indies to check up the effects of his previous venture, and organized it so the vaccine would continue reaching the corners of the empire. He would die nine years later.
The expedition remains little known in modern pop culture, it has notably returned to Spanish collective memory after the 2000s, generating a fair bit of fiction about it over there.
In media:
Comic Book- Primo Ramón drew and wrote a comic book about the expedition, Nuevo Mundo. Isabel Zendal en la expedición de la vacuna, in 2018.
- The graphic novel El mar recordará nuestros nombres by Javier de Isusi was released in 2021.
- The 2016 TV movie 22 Ángeles adapted the novel Ángeles custodios, referred below, under the writing of Miguel Bardem, cousin to Javier Bardem.
- Julia Álvarez's 2006 short story Saving the World takes again the point of view of Isabel Zendal.
- Almudena de Arteaga's novel Ángeles custodios has the expedition as its setting.
- The 2011 novel Los héroes olvidados by Antonio Villanueva Edo also addresses the expedition.
- Javier Neveo released another novel, Los niños de la vacuna, in 2013.
- A flor de piel, by Javier Moro, also stars Zendal during the expedition.
- Another novel about the expedition is Los niños de la viruela, authored in 2017 by María Solar.
- Cuarto Milenio explored the Balmis Expedition in November 2020.
- It is also addressed in the podcast Futility Closet by Greg Ross.
