Where Are the Cases of Coronavirus in the U.S.? Five People in Four States Test Positive

In the five days since the new coronavirus strain was found in a person in the United States, officials have identified the virus in four more people.

On Sunday, the Centers for Disease Control and Prevention (CDC) confirmed that two more cases of coronavirus were found, in Arizona and California. The additional cases brought the total in the U.S. to five, and because person-to-person transmission is expected to occur, the CDC said, the number of cases is likely to increase.

The virus, temporarily labeled 2019-nCoV, was first identified in Wuhan, China, in December and has since spread to 10 countries on four continents. Since this is the first time it's been identified in humans, health officials are still learning about the disease, which they said most closely resembles severe acute respiratory syndrome, or SARS.

Some people have reported very mild or even no symptoms, according to the CDC, but 2019-nCoV can also be deadly. As of Sunday, the death toll in China was 56, although China's government is now reporting up to 80 deaths. Of the cases reported in China, the World Health Organization (WHO) said about 16 percent involved people who became severely ill.

So far, every case in the United States has involved a person who recently visited the Chinese city of Wuhan, but person-to-person spreading is expected to occur. Although this will likely cause more cases, the CDC said it doesn't guarantee that the virus will be highly contagious. Human transmission happens on a continuum, so while some viruses, such as measles, spread rapidly, others aren't as contagious. The CDC said the risk to the American public is still low.

However, the U.S. agency said that it was a "very serious public health situation" and that it is working with officials in the states where patients have been identified to determine who else may have been exposed.

Washington State

On Tuesday, the CDC confirmed that the first U.S. case of 2019-nCoV was found in a patient in Washington. The person returned from Wuhan on January 15 and was treated at a medical facility in Washington before testing positive for the virus.


Three days later, the CDC confirmed that a second case was found in Illinois, also involving a person who had recently visited Wuhan. When the patient, a woman in her 60s, was admitted to a hospital for symptoms in line with 2019-nCoV, measures were taken to reduce the risk of the virus spreading to others, including hospitalizing the patient in an isolation room.

The city of Chicago said the woman returned to the U.S. before the CDC implemented screenings at Chicago O'Hare International Airport. The CDC first started conducting health screenings at Los Angeles International Airport, New York's John F. Kennedy International Airport and San Francisco International Airport on Friday, but expanded the order to include Chicago O'Hare and Hartsfield-Jackson Atlanta International Airport on Tuesday.

The woman "took the proper steps" to limit the risk to others, according to the city of Chicago, but officials from multiple agencies were working to identify anyone who may have been exposed.

coronavirus cases us illinois california arizona
A sign gives directions to St. Alexius Medical Center in Hoffman Estates, Illinois, on January 24, where a Chicago woman with the coronavirus is being treated in isolation. There have been five confirmed cases in the United States so far, affecting four states. Derek R. Henkle/AFP/Getty


California's first case of coronavirus was reported on Saturday in Orange County. The Orange County Health Care Agency's Communicable Disease Control Division said the case involved a traveler from Wuhan who was transported to a local hospital and isolated. The agency is planning to monitor anyone who had close contact with the patient and said the risk of local transmission was low.

On Sunday, the CDC confirmed a second case in California, this time in Los Angeles County. The Los Angeles County Department of Public Health said in a statement that the patient, who recently returned to the U.S. from Wuhan, was receiving care at a local hospital and that officials were working to identify anyone who may have been exposed.


The CDC also confirmed that a person in Arizona tested positive for the virus on Sunday. The person is a Maricopa County resident and a member of the Arizona State University community but does not live in university housing, according to the Arizona Department of Health Services (ADHS).

"This person is not severely ill and is currently in isolation to keep the illness from spreading," the ADHS said in a statement.

Along with the growing number of confirmed cases, NBC News reported there has been an increase in suspected cases in the U.S. Twenty-six states have collectively sent about 100 samples to the CDC for testing, according to the network. Twenty-five samples have tested negative, and, aside from the five positive results, the rest are pending.

Once the CDC receives a sample, it takes about four to six hours to diagnose a case. Right now, the agency is the only place testing can be done, but the CDC is working on sending a rapid test to individual states.