When did Coronavirus start spreading in China? Satellite images reveal new information

According to a new study by Harvard Medical School, satellite images of hospital parking lots in Wuhan show that the novel coronavirus might have been spreading in China as early as August. The study found that there has been a significant rise in the number of cars parked in August as compared to a year earlier. The keywords in internet searches associated with an infectious disease on China’s Baidu search engine was also high. 

In October 2018, the researchers counted 171 cars in the parking lots of Tianyun Hospital, which is one of Wuhan’s largest hospitals. Satellite data from a year later showed 285 vehicles on the same lot. There has been an increase by 67%. The traffic has also increased by 90% during that time. 

"Individual hospitals have days of high relative volume in both fall and winter 2019. However, between September and October 2019, five of the six hospitals show their highest relative daily volume of the analyzed series, coinciding with elevated levels of Baidu search queries for the terms 'diarrhea' and 'cough'," they wrote.

"The data is actually especially compelling because we saw increases in people searching for gastrointestinal disease -- diarrhea -- which were increasing at a level that we hadn't seen at all, historically, and we now know now that gastrointestinal symptoms are a really important marker for COVID," one of the researchers told CNN.

Reportedly, a lot of people who tested positive posessed symtoms of diarrhea.

"While we cannot confirm if the increased volume was directly related to the new virus, our evidence supports other recent work showing that emergence happened before identification at the Huanan Seafood market," according to him and his team. "These findings also corroborate the hypothesis that the virus emerged naturally in southern China and was potentially already circulating at the time of the Wuhan cluster."

Millions of people across the globe have been affected by the license since then. According to data released by John Hopkins University, more than 404,000 global deaths and more than 110,000 deaths due to COVID19 have been reported.