As reopening measures begin across the US and the world, it becomes increasingly clear that the road to normal – a time without social distancing, masks, and quarantines – will be a long one. Barring the discovery of an effective treatment, only a readily available and easily administered vaccine will allow a return to former ways of life.
The good news is that more than 125 vaccines are currently in development, according to the WHO. But most of these vaccines won’t make it to clinical trials, and many of those that do won’t be effective or safe enough to achieve licensure, says Peter Hotez, MD, PhD, dean of the National School of Tropical Medicine at Baylor College of Medicine. He adds that predictions that a vaccine could be ready by the fall are unrealistic. “We won’t see our first Covid-19 vaccines until late 2021 at the earliest,” he says.
To make a vaccine, scientists must first understand the structure of the virus, how rapidly the virus mutates, and whether those mutations affect the immune response, says the Center for Immunization Research’s Kawsar Talaat, MD, an assistant professor in International Health. A potential vaccine must then undergo rigorous testing. The quickest a vaccine has been developed to combat a novel pathogen is four years. And there are still no effective vaccines for some pathogens, such as HIV.