The coronavirus may have been around as early as August, a new study from the Harvard Medical School found.
The study relies on satellite images of hospital parking lots in Wuhan, China, and on internet search trends, CNN reported.
Harvard researchers said there were substantially more vehicles in parking lots at five Wuhan hospitals in the late summer and early fall, compared to 2018, CNN reported.
It also found an increase in searches of keywords associated with infectious diseases on China’s Baidu search engine.
Researchers saw a “steep increase” in volume starting in August and culminating with a peak in December, the team, led by Dr. John Brownstein, the chief innovation officer at Boston’s Children’s Hospital, wrote in a preprint posted on Harvard’s DASH server.