How Spain battled a previous pandemic by sending a group of orphans around the world as ‘human vaccines’

Spain’s desperate battle with the coronavirus pandemic has revived memories of a historic campaign to combat smallpox and the fate of a group of orphans that were used to carry the vaccine.  

The groundbreaking 19th century voyage was brought back into public consciousness in March, when the armed forces were called in to bolster the country’s coronavirus response, including disinfecting airports and care homes.  They dubbed the action “Operation Balmis”, after doctor Francisco Javier de Balmis, who led the expedition to Spain’s smallpox-ravaged colonies.  

More than 30,000 people have died from Covid-19 in Spain, which is now grappling with a second wave of the virus that has prompted a partial lockdown in the capital. A new emergency hospital that will treat coronavirus patients in Madrid pays another nod to the extraordinary smallpox mission: it has been named after Isabel Zendal, the orphanage rectoress who nursed the boys on the journey. 

Smallpox is thought to have accounted for hundreds of thousands of deaths in Europe each year at the end of the eighteenth century and tore through Spain’s colonies, decimating indigenous populations. Spanish and other European colonialists have often been blamed for spreading the disfiguring and frequently fatal disease.  

In 1803,  Balmis headed an ambitious expedition that set sail from the northern Spanish port of A Coruña to combat smallpox in its colonies. Led by military doctors, the mission’s  success depended on much younger participants: 22 boys, mostly orphans between three and nine-years-old, who transported the live vaccine in their bodies on the weeks-long sea voyage. 

They stopped first in the Canary Islands and went on to Puerto Rico and Venezuela. The expedition then split up with Balmis heading to Cuba, Mexico and the Philippines, while Catalan medic Josep Salvany took the vaccine to Colombia, Ecuador, Peru, Bolivia and Chile.  

In the cramped bowels of the ship on the journey from Spain to Puerto Rico the vaccine was passed between the boys, the most reliable method to prevent it from perishing. It consisted of a dose of cowpox, which the British scientist Edward Jenner had discovered made recipients immune from smallpox.

Liquid from the pustules that developed in a pair of vaccinated children was administered to a new pair every 10 days via scratches made on their arms, explained José Carro Otero, president of the Royal Academy of Medicine and Surgery in the northern region of Galicia, who is researching the lives of some of the orphans. While the side effects were milder than receiving a dose of smallpox, there was still a risk of fever and nausea.  

“Without the children, transmission of the vaccine would have been impossible,” said Carro. “They calculated how many children would be sufficient to maintain the chain, based on the time it would take to make the journey.”

The expedition is considered the world’s first mass vaccination effort and the recent remembering of the voyage pays tribute to a medical achievement some feel has never been fully recognised. 

“The importance of the mission isn’t just that they brought over the vaccine. They taught people how to administer the vaccinations and left the infrastructure to do it,” said Spanish author María Solar. Her novel, “Los niños de la viruela”, is a powerful portrayal of the lives of children at Isabel Zendal’s orphanage in A Coruña, from which 13 boys were chosen for the journey. 

Of all those involved, it is perhaps the role of the orphans who became human vaccines that has been underplayed most. Many of the boys are only recorded by first names in documents from the time and little is known of their ultimate fate. However, academics, writers and filmmakers are bringing their story out of the shadows.  

Solar’s book focuses on the experiences of the orphans leading up to the voyage, as they battle with the daily challenges of being social outcasts. “I felt that understanding the lives of these children who were going to carry the vaccine, their poverty, their dreams, would impact people more than recounting the journey itself,” Solar told The Independent. Published in 2017, the book has gone into multiple editions and was this year adapted into a stage play. Interest in the role of Zendal and the orphans was also spurred by the epic 2015 novel “A flor de piel” by Javier Moro.

There is scant official information on the orphans, but the traces that exist attest the tragedy of their circumstances. Records from the orphanages where they were abandoned as babies show some had been left with notes or scraps of fabric so they could be identified when their families came back for them. Often too poor to feed another mouth, few ever managed to retrieve their children. It is unknown whether parents of the boys who were sent on the expedition did ever return to collect them, only to find their sons had been dispatched to the other side of the world.  

“There were so many abandoned children being cared for by public institutions, it was easy to take them,” Solar said. “Today it would be absolutely unacceptable. But we have to imagine ourselves facing the disease that caused the most terror in the history of humanity.” She added that the vaccine had been proven to work, so was not simply an experiment, and that young children had also been chosen for a scientific reason: because they were considered to have been less exposed to the myriad diseases that afflicted adults.  

Five boys from Santiago de Compostela and four from Madrid joined those from A Coruña. All were orphans apart from one, Isabel Zendal’s own son. Of the 22 children enlisted, 21 were recorded as arriving in Latin America. It is uncertain whether the missing boy died on the journey or failed to depart from Spain.  

Balmis, Zendal and Salvany spent years on the mission, which was sponsored by the Spanish crown. More children were recruited along the way to keep the vaccine alive. Balmis returned to Spain in 1806, but Salvany died in Bolivia four years later. Zendal settled in Mexico with her son.  

According to American historian Michael M. Smith, the orphans from Spain were left in Mexico in 1804, where the viceroy was under a royal order to care for and educate them. But they again found themselves in poor conditions in an orphanage, prompting complaints from Balmis. Smith’s trail goes cold in 1809, by which time two of the boys had died, but the majority had been adopted by private citizens. “Although the king’s orders were never precisely carried out, the children’s fate in Mexico was perhaps better than it would have been if they had never left Spain,” Smith concluded.

Screenwriter Alicia Luna said the mystery surrounding the fate of the orphans had piqued public interest in their story. Luna wrote the script for “22 Angeles”, a 2016 movie for Spanish national television about the expedition. Based on a novel by Almudena de Arteaga, the film puts Zendal and the orphans at the heart of the portrayal.  

“Their story finishes in Mexico and we don’t know anything more about them. Did these children live, die, grow old? It would have been nice to be able to follow their path, to see what happened to them,” Luna said.  

Yet the boys’ bravery lives on. To mark the launch of Solar’s novel, a plaque commemorating  the five orphans from Santiago  was hung in an elegant reading room at the city’s parador. It is a simple reminder of their courage and of the luxury hotel’s bleak past – it once housed the orphanage in which the children were abandoned.  

“The book will pass,” said Solar, who comes from Santiago. “But the plaque with their names and ages will always be there, to commemorate what happened and what those children experienced.”