SAN DIEGO — Health officials said Monday they are investigating the first suspected case of coronavirus in San Diego County.

The County Health and Human Services Agency sent lab specimens Sunday to the Centers for Disease Control and Prevention. The results are expected back early Wednesday and will confirm or rule out the rare respiratory illness.

If the case is confirmed, it will be the first in San Diego County.

The patient traveled to China, including Beijing and other areas where infections of the virus have been reported, according to Dr. Wilma Wooten, county public health officer. The patient traveled by train through Wuhan, where the virus originated, but did not get off in the city.

When the patient returned home to San Diego County, they started showing symptoms and were admitted to a hospital. As of late Monday, the patient was in isolation at home, according to the county.

There are at least five confirmed cases of the coronavirus in the United States, including two cases in California, along with one in Washington state, one in Illinois and one in Arizona.

According to the CDC, the virus spreads through respiratory droplets from an infected person’s cough or sneeze, much like the flu. Symptoms include fever, cough and runny nose.

If you have not traveled through China where the virus is present, becoming infected is considered unlikely at this time, Dr. Wooten said.

“If you’ve not traveled to the regions, you don’t know anyone who has traveled to the region, currently, right now, the risk is very low,” Wooten told FOX 5.

Currently, there is no vaccine or medication to treat the virus.

“Washing your hands is very important,” Dr. Wooten said. “Not touching your eyes, nose and mouth is very important to prevent the spread.”

A spokesman for San Diego International Airport, which does not have direct flights from China, said Monday they have not received instructions from CDC or county health officials to screen passengers for the virus.

“The CDC has provided SAN with specific guidance to help local EMS providers responding to medical calls at the airport assess and identify potentially infected travelers,” Director of Communications Jonathan Heller wrote in an email to FOX 5.

The airport has posted information in the International Arrivals area for passengers who have recently traveled to China and are feeling ill.