Study shows why second dose of COVID-19 vaccine shouldn’t be skipped

The second dose of a COVID-19 vaccine induces a powerful boost to a part of the immune system that provides broad antiviral protection, according to a study led by investigators at the Stanford University School of Medicine. The finding strongly supports the view that the second shot should not be skipped. “Despite their outstanding efficacy, little is known about how exactly RNA vaccines work,” said Bali Pulendran, PhD, professor of pathology and of microbiology and immunology. “So we probed the immune response induced by one of them in exquisite detail.” The study, published July 12 in Nature, was designed to find out exactly what effects the vaccine, marketed by Pfizer Inc., has on the numerous components of the immune response. The researchers analyzed blood samples from individuals inoculated with the vaccine. They counted antibodies, measured levels of immune-signaling proteins and characterized the expression of every single gene in the genome of 242,479 separate...