As the world anxiously pins its hopes on vaccines to halt the coronavirus pandemic, scientists are still learning from the first global scourge to be eradicated by vaccination. Ancient-DNA sleuths analyzing Civil War-era artifacts with 21st-century sequencing techniques have recreated five genomes of viral vaccines mustered to fight smallpox in the 1860s, finding they were quite different from those used a century later to finally wipe out the disease. Remarkably, scientists were able to recover viral molecules from the scabs, blisters, pus, and other biological traces lingering on knife-like lancets, tin boxes, and glass slides tucked into leather vaccination kits discovered at a Philadelphia museum of medical history. Doctors carried these custom-built cases to inoculate soldiers and citizens from smallpox while the North and South fought on nearby battlefields more than 150 years ago. Vaccines were made not in labs or factories then, but instead were grown in a human chain of people exposed to related but mild cousins of smallpox.

 

Credit: iStock, poba

Read more STAT…