(CN) — Long before the pandemic of 2020, there was the fear of a smallpox outbreak during the American Civil War. Remarkably, modern researchers were able to find traces of the smallpox vaccine strains used from that era and published their findings Sunday in the journal Genome Biology.
Immunizations were in practice before the start of the war in 1861, but the infectious smallpox disease during the war prompted some haphazard field vaccinations.
According to the Smithsonian, 40% of Union soldiers who contracted the disease died. Gruesome historical anecdotes include self-immunizations between fellow soldiers who would try to stick themselves with pocket knives smeared with pus so they could build their own immunity.
In 1796, vaccinations became widespread thanks to English physician Edward Jenner who observed that exposure to a milder illness could provide protections against future outbreaks of smallpox.
By the late 1970s, the last naturally occurring case of smallpox was diagnosed and the virus was officially declared eradicated by the World Health Organization in 1980.
The study published Sunday stemmed from the researchers’ interest in the success of the eradication of smallpox via vaccination, according to lead researcher Ana Duggan with the Public Health Agency of Canada. The study sought to understand what vaccine strains were used to prevent infection by naturally occurring smallpox.
“In the context of contemporary research, especially on a day when we see so much news on the truly global effort to develop vaccines for the SARS-CoV-2 virus, it is important to reflect on and celebrate the history and successes of past vaccination efforts,” said Duggan in an email.
Researchers examined vaccination kits used during the Civil War era, which included small lancets and glass plates to gather samples, like scab materials. Study authors say they were able to gather samples from the organic and nonorganic parts of the kits, including the tin boxes and slides, which provided a peak into a different era of medical history.
“Vaccination is a wonderful process with a rich medical history that we should celebrate,” said lead researcher Ana Duggan with the Public Health Agency of Canada in a statement. “Medical museums are incredible repositories of our past and of our collective history. The new tools we develop in this work allow us to begin to investigate how medical sources, procedures and techniques have changed through time.”
The study shows that in the 1860s and 1870s, medical practitioners used vaccinia virus or VV that was being tested on human subjects in Philadelphia. A weaker relative to smallpox was introduced to the host, typically by exposing pus or scabs to a scratch or cut in the skin and the host subject’s body could develop their own immunity.
The vaccinia strain found in the kits are considered distant in terms of the evolutionary makeup when compared to say smallpox according to the study authors and the slow rate of mutation for vaccinia likely provides for “distant” protection.
The smallpox disease killed millions of people and a vaccine that prevented that risk of death was a tremendous achievement, Duggan said in an interview.
“As we search for a SARS-CoV-2 vaccine, the work of Edward Jenner and subsequent physicians around the world to eradicate smallpox should serve as an inspiration to the value and potential of vaccine research and a reminder that effective vaccines can be quite evolutionarily distant” from the etiological agent or virus strain the vaccines are designed to protect against, Duggan said.
Study authors say their technique to recover viral molecules from the field kits will provide new avenues to explore medical history, but not just organic samples but inorganic as well.