A 15th confirmed case of coronavirus has been identified in the U.S., the Atlanta-based Centers for Disease Control and Prevention announced Thursday morning.

The patient is among a group of people under a federal quarantine order at JBSA-Lackland in Texas because of their recent return to the U.S. on a State Department-chartered flight that arrived on Feb. 7, 2020.

This is the first person under quarantine at JBSA-Lackland who had symptoms and tested positive for COVID-19. The individual is currently isolated and receiving medical care at a designated hospital nearby.

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On Wednesday, Dr. Nancy Messonnier, director of CDC’s National Center for Immunization and Respiratory Diseases, told media during a conference call “we can and should be prepared for this new virus to gain a foothold in the U.S.

“The goal of the measures we have taken are to slow the introduction and impact of this disease in the United States but at some point, we are likely to see community spread in the U.S.,” Messonnier said. “Or other countries and this will trigger a change in our response strategy. We are focusing now on preparing in other areas, including development of guidance for our health care practitioners, and planning for increased demand on our health care system.”

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On Thursday, China reported 254 new deaths and a spike in virus cases of 15,152, after the hardest-hit province of Hubei applied a new classification system that broadens the scope of diagnoses for the outbreak, which has spread to more than 20 countries.

The couple's son says they are doing OK.

Japan also reported its first death, a woman in her 80s who had been hospitalized since early February. Two other places outside mainland China — Hong Kong and the Philippines — have previously confirmed one death each.

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The new diagnostic approach came on the same day that Hubei and its stricken capital, Wuhan, replaced their top officials in an apparent response to public criticism of local authorities’ handling of the epidemic.

How does coronavirus differ from the flu? Coronavirus, also known as 2019-nCoV, has infected 40,171 people and killed more than 900 in China. With flu season in full effect and the spread of 2019-nCoV, many have become worried about infection. But how do the two illnesses compare? Here are a few differentiating factors. Symptoms and SeverityFlu symptoms include fever, cough, sore throat and muscle aches. Coronavirus includes fever, cough and shortness of breath. Death Rate 0.05 percent of thos

The total deaths in mainland China since the outbreak began in December stood at 1,367, with the total number of confirmed cases mounting to 52,526. This figure now includes more than 13,000 cases of “clinical diagnosis” in Hubei, which appears to include those based on a doctors’ analysis combined with lung imaging, as opposed to waiting for laboratory test results.

The Associated Press contributed to this report.