A Century-Old Vaccine Fails to Protect Against Covid
An old tuberculosis vaccine known to bolster the immune system did not prevent Covid infections among health care workers, scientists reported on Thursday.
But the trial was shorter and smaller than originally designed, and the investigators said that the results did not rule out other potential benefits associated with the vaccine, known as B.C.G. for bacille Calmette-Guerin.
The study, published in The New England Journal of Medicine, was the largest clinical trial of the vaccine’s potential to protect against Covid infections. B.C.G. was developed in the early 1900s to combat TB, but has since also been shown to confer protection against other illnesses, including respiratory diseases.
The trial of health care workers began in March 2020, during the early days of the pandemic, when no effective treatments for Covid were available and a new vaccine against the highly infectious disease seemed to be a remote fantasy. The hope was that the old vaccine might be repurposed to save lives.
Source: The New York Times
