When Francisco Javier de Balmis arrived in Mexico in 1804, he did so with 22 children infected with smallpox, a disease that was killing millions of people around the world.
But far from spreading (even more) the deadly disease, those children had a mission: to be part of the first international humanitarian mission.
They were there to carry out one of the first vaccination days to cross the ocean, from Europe to America.
But the success of the expedition led to a new journey, this time to the other side of the planet, crossing the Pacific.
They were going to the Philippines.
And for this new feat, Balmis recruited 26 other children. And as he had done with the others, he infected them with the virus.
The operation was named after Royal Vaccine Philanthropic Expedition, or Operation Balmis in honor of the Spanish military doctor who carried it out.
And much has been said about her and the role played by the 22 original children who left the port of A Coruña, in Spain, on November 30, 1803.
But little of the other 26 children who sailed from Acapulco to Manila.
Until now, since the General Archive of the Indies in Seville brought to light new documents about that second part of the expedition.
Now more details are known about who these children were, where they came from and how old they were.
Talking about children becomes even more important, since the disease was especially deadly among minors.
These documents are part of an exhibition on the Balmis Expedition that the Archivo General Indias will keep open until September 15.
The need for a vaccine
In the 18th century, smallpox was one of the greatest dangers facing society.
Although the records point to a possible origin in North Africa, it was travel and the growth of the world population that facilitated the expansion of the Variola virus.
For centuries the disease decimated entire populations.
In Europe it was especially devastating due to its virulence amid the excessive growth of cities.
Up to a third of the sick died. But those who survived the disease were disfigured, with deep marks on the skin.
During the colonization of America, smallpox wiped out indigenous communities, which did not have natural defenses.
For many years, people searched for any method that would protect them from disease.
One of them was the variolation, which consisted of infecting a healthy person with a dose of the virus from a patient so that they would become slightly ill and thus remain immune.
It was a method similar to the vaccines that came later, although more rudimentary.
But this practice was not entirely reliable. The person could become seriously ill, or contract another illness.
And it wasn’t until 1796 that a rural doctor in England came up with a much safer solution.
Edward jenner observed that women who milked cows contracted a non-fatal strain of the disease.
Taking samples from the hand of a milker, he set out to inoculate a patient with the first vaccine, an eight-year-old boy.
The boy contracted the cowpox strain. But he did not contract the human, which was the mortal.
He had been immunized.
Jenner not only found that it was possible to immunize people from human smallpox, but that the method could be passed from human to human, a key piece of information to bring the vaccine to other countries.
Of Spain to the new world
For years, the vaccine method remained in Europe, where communication and proximity between countries favored transportation.
But the vaccine had a setback: it worked only as long as the virus was active.
That gave the vaccine a duration of only 12 days. Beyond that period, the inoculation was ineffective.
Unlike modern times, science in the 18th and 19th centuries was much more rudimentary. The cooling methods that we have today did not exist.
If it was already difficult to transport the vaccine in Europe, crossing the Atlantic Ocean was a daunting task.
And for King Carlos IV of Spain, getting the vaccine to the Spanish colonies was crucial.
Even his daughter Maria Teresa had died of smallpox.
Persuaded by the court physician, he gave the order to undertake an expedition to bring the vaccine to America.
And that doctor was Balmis.
How they did it?
They set sail from Galicia together with 22 children, between 3 and 9 years old, who had never contracted smallpox before.
They started by infecting two of them. And after ten days, they took samples from the pustules of the infected and they infected two more.
And so they came to America with the fresh serum.
They reached the port of La Guaira in Venezuela, where the expedition was divided.
One of the members, José Salvany y Lleopart, left for the other countries of South America.
Balmis instead left for Caracas, where he founded the Central Vaccine Board. And from there to Mexico.
And from Acapulco to the Philippines
With the success of the expedition, a question remained: What would Spain do with the other overseas territories?
The countries of America were not the only colonies under the rule of the Spanish Empire. The Crown had spread to other territories in Asia, much further afield.
The Captaincy General of the Philippines was one of those territories.
The solution was simple: recruit more kids.
And this time they sailed from Acapulco, in February 1805, with destination to Manila.
New documents recently released, signed by Balmis in February 1805, offer some details about these children.
As the children came from different territories of Mexico: Valladolid, Guadalajara, Querétaro, Fresnillo, Sombrerete and León.
“The city of Zacatecas presents six children to Balmis for the expedition to the Philippines,” reads one of the documents provided by the General Archive of the Indies to BBC News Mundo.
Six five-year-olds “perfectly dressed, with arms embroidered on their chests,” the document continues.
It is now known that three of the children were of unknown parents, five of them were knownía only the mother (they could be single or widowed) and six of them were mestizo.
In addition, Balmis signed so that the children, once the trip to the Philippines was completed, would be returned to their parents, who were paid a stipend.
End of the expedition
After completing the mission in the Philippines, the expedition returned to Mexico.
But Balmis did not, who returned to Spain … on the other side, stopping earlier in China, where the vaccine had not yet arrived.
And he finally arrived in Lisbon in 1806. The whole expedition as a whole lasted almost three years.
But the vaccine continued to be given to thousands of children over the next several years.
However, despite the fact that the expedition was considered a historic milestone for its simplicity and success, smallpox continued to be a threat for many years to come.
In the 20th century alone, it killed 300 million people, according to the World Health Organization.
After an extensive campaign, it became known eradication of the disease in 1979.
Finally, on May 8, 1980, the WHO accepted the report certifying the eradication of smallpox.
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