A new study in California has found the number of people infected with coronavirus may be tens of times higher than previously thought.
The study from Stanford University, which was released Friday and has yet to be peer reviewed, tested samples from 3,330 people in Santa Clara county and found the virus was 50 to 85 times more common than official figures indicated.
To ease the sprawling lockdowns currently in place to stop the spread of Covid-19, health officials must first determine how many people have been infected. Large studies of the prevalence of the virus within a region could play a key role, researchers say.
“This has implications for learning how far we are in the course of the epidemic,” said Eran Bendavid, the associate professor of medicine at Stanford University who led the study. “It has implications for epidemic models that are being used to design policies and estimate what it means for our healthcare system.”
The study marks the first large-scale study of its kind in the US, researchers said. The study was conducted by identifying antibodies in healthy individuals through a finger prick test, which indicated whether they had already contracted and recovered from the virus. Volunteers for the study were recruited through Facebook ads, which researchers say were targeted to capture a representative sample of the county’s demographics and geography.