Worried you have the coronavirus? Here's exactly what you should do.

For starters, don't panic: "The vast majority of cases are going to be mild, and people are going to recover just like they do from a cold or flu-like illness."

Breaking News Emails

Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.
SUBSCRIBE
By Elizabeth Chuck

With a growing number of cases of the new coronavirus confirmed across the United States, having a sore throat or some sniffles might feel like a cause for concern. But in most cases, there is no reason to worry, experts say.

If you have symptoms of the coronavirus, which include fever, cough and shortness of breath, here are the steps that doctors and public health officials recommend you take.

Full coverage of the coronavirus outbreak

Don't panic.

While researchers are still learning about the new coronavirus, most people sickened by it appear to not get all that ill.

"The one thing we really don't need is mass hysteria," said Dr. Robert Murphy, executive director of the Institute for Global Health at the Northwestern University Feinberg School of Medicine and an infectious diseases professor. "Eighty percent of people have such minor symptoms, they don't actually require any medical care at all. The 20 percent who do feel quite ill need to be evaluated, and some of them will require hospitalization and some of them will require intensive care."

Those most at-risk for severe symptoms include senior citizens and/or people with underlying medical conditions, such as cardiovascular or lung disease, cancer or diabetes, he said.

As of Friday evening, there were more than 300 confirmed cases of the coronavirus across the United States. Some have already recovered.

Before you do anything else, call your health care provider.

If you are worried you might have the coronavirus, pick up the phone before you seek medical treatment. The reason for this is twofold: In very mild cases, your doctor might be able to give you advice on how to treat your symptoms at home without needing to see you in person, which would reduce the number of other people you expose.

"The vast majority of cases are going to be mild, and people are going to recover just like they do from a cold or flu-like illness," said Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security and an infectious diseases doctor.

In more serious cases, where medical treatment might be necessary to assist with breathing issues or other problems, an urgent care center or a hospital emergency department will benefit from advance notice of your arrival. They may have a special entrance they want you to come in through so you don't expose other patients on your way in, or a mask they want you to put on, Adalja said.

Download the NBC News app for full coverage of the coronavirus outbreak

Not everyone needs to be tested, experts say. If you have been in close contact with someone diagnosed with the coronavirus or have recently traveled to an area where the virus is spreading, and you develop a fever, a cough or difficulty breathing, the Centers for Disease Control and Prevention recommends you call a health care professional for guidance on whether to be tested.

This advice has been echoed by local public health districts. In Snohomish County, Washington, where there are at least four confirmed cases of the coronavirus, officials urged the public to call their health care provider if they think they have been exposed or feel ill with "only mild cold symptoms." They advised against going to an urgent care clinic or a hospital to get tested in those situations.

"Doing so displaces other patients who truly need urgent care and increases the risk of spread of respiratory infections in health care settings. Furthermore, there is little personal health value in pursuing COVID-19 testing of patients who are not severely ill or part of a public health investigation," the Snohomish Health District said in a statement.

Even if you have not had prolonged contact with known coronavirus patients, but are concerned you might have caught the illness, calling your doctor first is the best course of action.

"If you have any anxiety or reason to believe you have coronavirus infection, or heck, even if you have influenza, call your health care provider, because you don't want to just show up in the waiting room and give it to everybody else," said Dr. William Schaffner, an infectious diseases specialist at the Vanderbilt University Medical Center.

What your doctor recommends you do will depend on the severity of your symptoms. Shortness of breath, an unremitting fever or feeling extremely weak require medical attention, which could include visiting an urgent care center or an emergency department, according to Johns Hopkins' Adalja.

"Otherwise, I would treat it symptomatically. That might include taking medicine to reduce fever, or cold and flu medicines to reduce symptoms," he said.

Stay home until your symptoms go away.

As with any illness, it's best to keep your germs to yourself.

"Don't go to work and spread it to your co-workers. Don't go to the gym. Hunker down."

"Don't go to work and spread it to your co-workers. Don't go to the gym. Hunker down," Schaffner said.

Because the coronavirus is believed to be most contagious when patients are symptomatic, the CDC has asked those with it to isolate themselves until their cough, fever and other symptoms go away — which is likely to be at least a week or two, according to Northwestern's Murphy.

But because much is not known yet about the virus, the contagious period could be longer than that, Murphy added.

For close contacts of the infected person, or those who have had prolonged contact within six feet of a confirmed patient, the CDC considers the incubation period to be 14 days, during which they should be quarantined and monitored for symptoms.

As for others in the community with whom those close contacts have been in touch, "the contact of the contact is probably not going to be a problem. Now, if the person gets sick, they move up the ladder and then they're a real contact," Murphy said.

And if you are not sick...

The coronavirus is believed to spread mostly through respiratory droplets — which are dispersed when a sick person coughs, the Rhode Island Department of Health spokesman Joseph Wendelken said over the weekend, when the state announced its first two cases. He said most people should still go about their normal lives.

“If someone is not exhibiting any symptoms, there is no need to change your daily routine,” he said.

While the CDC has warned that Americans should be prepared for a coronavirus outbreak in their communities, guidance on how to stay healthy has mostly revolved around commonsense measures, including washing your hands and not touching your face.

Those who are medically frail or elderly should take extra precautions to not expose themselves to the virus by avoiding large gatherings, experts said. For everyone else, making any major changes is an individual decision, not an edict.

"We certainly ought to be prudent," Schaffner said. "Maybe I'll watch TV instead of going to the movies. This is maybe not the time to go out and spend a lot of time at the mall shopping."

But, Schaffner pointed out, those are good measures to take during cold and flu season anyway.

"Please don't panic. Remember that even if you should have coronavirus infection, most of the infections, we're now learning, are fortunately rather mild," he said.

Follow NBC HEALTH on Twitter & Facebook.