Health officials are reporting more than 35,000 cases of the coronavirus in the U.S. and roughly 470 deaths, according to researchers .

At least seven states have seen more than 1,000 cases: Washington, New York, California, New Jersey, Illinois, Michigan and Florida.

Last week, President Donald Trump released coronavirus guidelines that were set to last 15 days. The suggestions include limiting gatherings to 10 people or fewer. Trump said on Twitter Sunday night that a decision as to whether to extend the timeline would come at the end of the period, which is next week, and he warned that "we cannot let the cure be worse than the problem itself."

Trump activated the National Guard in Washington, New York and California and approved the states' "major" disaster declarations. He said medical facilities will also be built in the three states.

Photos: America at Standstill View All 30 Images

As of Sunday, at least eight states have ordered residents to stay home, shelter-in-place or stop non-essential travel: Delaware, Ohio, Louisiana, New Jersey, California, New York, Illinois and Connecticut.

Treasury Secretary Steven Mnuchin on Sunday said lockdowns of the public are likely to last until early June.

Despite California's shelter in place order, Los Angeles Mayor Eric Garcetti said that outdoor areas were packed over the weekend and announced the closure of the city's parks.

"This weekend we saw too many people packing beaches, trails and parks. So we are closing sports and recreation at @LACityParks and closing parking at city beaches. That doesn't mean gather elsewhere. This is serious. Stay home and save lives," he tweeted on Sunday night.

Sen. Rand Paul of Kentucky on Sunday became the first senator to test positive for the virus.

Trump tweeted on Sunday night: "My friend (always there when I've needed him!), Senator @RandPaul, was just tested 'positive' from the Chinese Virus. That is not good! He is strong and will get better. Just spoke to him and he was in good spirits."