The research that became the Cell study began in 2017, when Netea’s team recruited patients who were visiting the hospital at the University of Athens Medical School. Most were around 80 years old. Netea was nervous about patients having an adverse reaction to the vaccination, itself. In aging patients, there’s always a risk that an immune response can overfire, and BCG has traditionally been given to newborns, not the aged.
Then, Covid-19 hit, and observational studies done by scientists such as Luis Escobar, a disease ecologist at Virginia Tech in Blacksburg, Virginia, hinted that nations where newborns get BCG shots are associated with lower Covid-19 mortality. Netea and his colleagues decided to fast track their analysis. In mid-May, they learned that the vaccinated patients had 80 percent fewer moderate-to-severe respiratory infections.
“That is pretty damn good,” says Kim Mulholland, a vaccinologist at the Murdoch Children’s Research Institute in Melbourne, who was more skeptical of broad beneficial effects of vaccines before this study. “This study left me with the feeling that I should go out and get a BCG vaccine.”