A man wears a medical mask on the subway as New York City confronts the coronavirus outbreak on March 11, 2020 in New York City.

Some of the most powerful lobbyists in Washington said Thursday that corporate leaders are growing increasingly concerned that the Trump administration and Congress don't have a handle on the widening coronavirus crisis.

Lobbyists interviewed by CNBC said executives flooded their offices with calls Thursday, after President Donald Trump's Wednesday night address to the nation about coronavirus failed to calm markets, leading to the worst day for U.S. stock markets since 1987's "Black Monday" market crash.

These business leaders are looking for answers about what Capitol Hill and the White House are going to do to assist the economy and combat the spread of the coronavirus, known as COVID-19.

At least 38 deaths and 1,300 infections have been reported in the U.S. Trump and Congress have come under fire for the lack of an efficient response to the coronavirus. States are calling for more test kits and funding for a better response.

House Democrats, Republicans and the White House on Thursday were working on another bill to respond to the virus.

A lobbyist close to President Donald Trump, who declined be named as conversations with clients are deemed private, told CNBC that clients were dealing with many coronavirus issues. This lobbyist noted that companies in the pharmaceutical industry are asking about any potential price gouging legislation as officials such as New York Gov. Andrew Cuomo call for businesses to stop raising prices on products such as Purell hand sanitzer.

Scott Mason, a senior policy advisor at lobbying shop Holland & Knight, told CNBC that his clients, which have included Google parent Alphabet, Nestle and Peabody Energy, have struggled to hold meetings in Congress because many lawmakers have decided to often hold discussions over the phone instead of in person. Mason was once a member of Trump's campaign and transition teams.

"Clients and firms are certainly impacted by travel restrictions," Mason said. "Hill access and markets with lots of adjusting day by day on the fly," he said, describing the concerns of clients.

Another lobbyist close with House Speaker Nancy Pelosi, who declined to be named because the conversations were deemed private, said clients are constantly calling about what to do next.

"Everybody is upside down. All the clients are upside down," this person said. The lobbyist also noted that airlines have called their offices to discuss upcoming cancellations and the partial travel ban from Europe that Trump announced Wednesday during his speech.

Steve Elmendorf, who was a senior advisor to former House Democratic leader Dick Gephardt for 12 years, initially only responded in a text with the word "everything" on Thursday when asked what his clients are concerned about when it comes to the virus. He declined to comment further at the time because he was so busy taking calls from businesses who were in a panic. Elmendorf's clients have included Goldman Sachs, Visa, Amazon, Bloomberg Philanthropies and Blackstone Group, among many others.

Later in the day, he explained to CNBC that clients are informing him that they don't believe the government has a handle on the public health threat with a lack of testing and treatment needs. The other criticism that Elmendorf has heard from leading businesses is that the economic damage from the coronavirus is going to be "deeper than policy makers may realize and significant stimulus is going to be needed to stabilize the economy and the markets," he said.

Still, these worries have been brought directly to congressional leaders and White House officials and Elmendorf senses the government is stunned with what they're seeing from the virus as it spreads throughout the country.

"It's like 9/11. People are shell-shocked," he said.