"U.S. healthcare system is being pushed to its limit,", said Dr. Rishi Desai, the chief medical officer at a health education platform named Osmosis.

Dr. Desai said hospitals and ICUs are being filled up in states like Arizona and Florida and Texas. He also added that the opportunity window for curbing the virus spread is closing, as the confirmed cases gradually reach local hospitals' capacity.

Although U.S. testing capacity has increased over the past months, reaching about 600,000 tests per day, Dr. Desai said the U.S. needs more, around 1 million tests per day.

A number of measures like social distancing rules need to happen, and they "need to happen really fast", said Dr. Desai, if the U.S. wants to close down states that are hot spots.