(CNN) Hope for treating the novel coronavirus could be on the horizon, as the first US study of a drug to treat the illness is underway.

So far, there is no cure or vaccine for the virus, which has infected more than 80,000 people and killed more than 2,700 worldwide in the past few months.

News of the drug testing came Tuesday, just as a federal health official warned that the virus will eventually start spreading in US communities.

A clinical trial to evaluate the safety and effectiveness of the antiviral drug remdesivir in adults diagnosed with coronavirus started at the University of Nebraska Medical Center in Omaha, the National Institutes of Health said.

The first participant is an American who was evacuated from the Diamond Princess cruise ship docked in Japan.

Also on Tuesday, top officials at the Centers for Disease Control and Prevention warned about the potential spreading of coronavirus in the US.

"We expect we will see community spread in this country," said Dr. Nancy Messonnier, director of the CDC's National Center for Immunization and Respiratory Diseases.

"It's not so much a question of if this will happen anymore, but rather more a question of exactly when this will happen and how many people in this country will have severe illness."

The US has 60 confirmed cases, health officials said Wednesday, a number that is expected to grow.

"We are asking the American public to work with us to prepare in the expectation that this could be bad," Messonnier said.

President Donald Trump on Wednesday placed Vice President Mike Pence in charge of the US government response.

The President told reporters: "We'll spend whatever is appropriate. Hopefully, we won't have to spend so much, because we really think that we've done a great job in keeping it down to a minimum."

Clinical trial for a treatment

There are currently no specific medicines approved by the US Food and Drug Administration to treat novel coronavirus. Without one, a top infectious disease doctor said, the US could see mortality rates from the coronavirus similar to those in China.

The Chinese Center for Disease Control and Prevention has calculated a case fatality rate of about 2% for the novel coronavirus -- meaning about 2% of those known to be infected have died. That's higher than influenza, which is about 0.1%, but much lower than severe acute respiratory syndrome, or SARS, (9.6%) and MERS, Middle East respiratory syndrome (35%).

"I think we would expect something similar to that because we don't have an antiviral drug," Dr. Anthony Fauci told CNN's Chris Cuomo Tuesday night on "Cuomo Prime Time."

"The people who are dying who require intensive care, for example in an intensive care unit -- maybe even intubation for respiratory assistance in breathing -- the Chinese have that. They have a pretty good system, and yet you're still seeing the 2% mortality. ... So if, in fact, we do get a pandemic that does impact us in this country, I think you're going to see comparable types of morbidity and mortality."

Remdesivir, the drug being tested at the University of Nebraska Medical Center, was previously tested in humans for Ebola and in animals for MERS and SARS.

There are clinical trials of remdesivir going on in China, and the National Institute of Allergy and Infectious Diseases developed the current study to match those trials, the NIH said in its news release.

Participants in the US treatment group will receive 200 milligrams of remdesivir intravenously when they're enrolled in the study. They will receive another 100 milligrams while they are hospitalized for up to 10 days total. A placebo group will receive a solution that resembles remdesivir but contains only inactive ingredients, the NIH said.

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US cases rise to 60

The number of coronavirus cases in the US rose to 60, Health and Human Services Secretary Alex Azar said Wednesday.

Of the other 15 cases, many had recently been to Wuhan, China, or are the spouse of someone who recently came back from Wuhan. Azar said the circumstances of the most recent case were not immediately known.

The CDC is employing a twofold approach, working to contain the virus while also implementing strategies to lessen the impacts on communities, Messonnier told reporters.

"We've also enacted the first quarantine of this scale in the US, and are supporting the State Department and (Department of Health and Human Services) in repatriating citizens from high-risk areas," she said.

In addition, the center is tracking and isolating cases when it can, issuing travel advisories for affected countries and taking on the increasingly difficult task of preventing the introduction of new cases, most notably at points of entry into the United States, she said.

Messonnier described the containment strategies as "largely successful" and said they were geared toward "buying us more time to prepare."

Health and Human Services Secretary Alex Azar leaves after speaking during a press conference on the coordinated public health response to the 2019 coronavirus.

What to look for and what to do

The symptoms of coronavirus are similar to those of a common cold. The virus usually causes a mild to moderate upper respiratory tract illness , with symptoms including a runny nose, cough, sore throat, possibly a headache and maybe a fever, which can last for a couple of days.

For those with a weakened immune system, the elderly and the very young, there's a chance the virus could cause a lower, and much more serious, respiratory tract illness such as pneumonia or bronchitis.

People may be able to reduce their risk of infection by avoiding those who are sick, avoiding touching their eyes, nose and mouth, and washing hands often with soap and water and for at least 20 seconds.

Most of the time, symptoms will go away on their own and experts advise seeking care early. People with symptoms that feel worse than a standard cold should see their doctor.