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There are currently over 3,700 confirmed COVID-19 cases in the U.S., according to Johns Hopkins University. But there's another problem when estimating how quickly the virus is spreading: no one knows exactly how many COVID-19 cases are prevalent in the U.S., according to Dr. John Brownstein, chief innovation officer at Boston Children's Hospital.

“We need to be careful about our case count – there are clearly more cases out there,” said Brownstein, who noted that “confirmed cases” do not accurately reflect the number of cases that are in the United States but rather only reflect the number of patients that have been tested and are positive for COVID-19.

Both private and government organizations have taken unprecedented steps in slowing the spread of the virus. The NBA, NHL and MLB have suspended their seasons to avoid close quarters contact among fans and players. Local governments including in New York and Los Angeles announced over the weekend they were shuttering businesses such as bars and entertainment venues.

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