The Centers for Disease Control and Prevention on Tuesday confirmed the first U.S. case of a deadly new coronavirus that has killed six people in China.
The CDC and Washington state officials said the man, in his 30s, was in good condition at Providence Regional Medical Center in Everett. The symptoms presented Sunday and the diagnosis was confirmed Monday.
Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases, called the news "concerning," particularly in light of recent reports that the virus has begun to spread from person to person.
"The confirmation of human-to-human spread in Asia certainly increases our concern," Messonnier said.
The CDC, which last week began enhanced health screenings at airports in San Francisco, New York and Los Angeles, said Atlanta and Chicago would be added to the list. All traveling from Wuhan, China - where the outbreak began - to the U.S. are now being rerouted to these airports, officials said.
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Hundreds of people in China have been diagnosed with the virus in the last few weeks. Most of the cases were reported the central city of Wuhan. But it has spread to other areas of the country, and a handful of cases have been diagnosed in Thailand, South Korea and Japan.
The World Health Organization is gathering a panel of experts on coronavirus Wednesday in Geneva, Switzerland, to determine whether the outbreak constitutes an international public health emergency and how it can be managed.
Many of the initial cases were linked to a seafood market in Wuhan, but Chinese health officials said this week that human-to-human transmission has been confirmed.
The coronavirus may lead to a severe form of pneumonia which may be deadly, said Robert Glatter, an emergency physician at New York's Lenox Hill Hospital. People with a history of chronic lung disease may be at higher risk for "adverse outcomes," he said.
"We must be vigilant to ensure that adequate screening processes are in place at all US airports," Glatter said.
Coronaviruses are a large family of viruses that cause illness ranging from the common cold to more severe diseases such as pneumonia to Middle East respiratory syndrome, known as MERS, and severe acute respiratory syndrome, or SARS. Common signs of infection include fever, cough, shortness of breath and breathing difficulties. In more severe cases, infection can cause pneumonia, severe acute respiratory syndrome, kidney failure and death.
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The virus can be spread from animals to people. But it also can be spread by coughing, sneezing and through close contact with an infected person or an object carrying the virus.
Coronaviruses, Ebola and SARS are zoonotic, meaning they are transmitted between animals and people. Ebola was carried by fruit bats, which spread it to other animals. SARS was transmitted from civet cats to humans and MERS from camels to humans.
There is no vaccine yet, although nine studies are examining coronavirus vaccine development. And while there is no specific treatment for the coronavirus, recommended measures are similar to those for cold, such as rest and drinking a lot of fluid.
This article originally appeared on USA TODAY: China coronavirus outbreak: CDC confirms 1st US case in Washington