A second patient in the United States has been diagnosed with Middle East Respiratory Syndrome, or MERS, a virus first identified in Saudi Arabia that's new to humans.
In making the announcement, U.S. Centers for Disease Control and Prevention (CDC) director Thomas Frieden called the second confirmed case of MERS "unwelcome but not unexpected" and said there is no cause for alarm at this time.
"Our experience with MERS so far suggests that the risk to the general public is extremely low," he said. "It is behaving relatively like the SARS [Severe Acute Respiratory Syndrome] coronavirus in that transmission requires close contact -- for example caring for someone when they are sick at home, or sick in the hospital. And it involves caring for someone who is infectious with the disease."
The new U.S. case involves a health care worker who was caring for patients with MERS in the Saudi Peninsula. The unidentified patient is in isolation at a hospital in the Orlando, Florida area. U.S. public health officials said the patient was in good condition.
Florida's State Surgeon General and Secretary of Health, John Armstrong, says the virus is being monitored, and the good news is that it has not changed.
"That means that we are able to find patients earlier, protect them and others from spread, and get a better handle on how to stop the disease transmission," he said.
The first case of MERS in the U.S. state of Indiana was announced on May 2. Officials said that patient's DNA has been sequenced and there's nothing to suggest the virus has become more virulent. No secondary infections have been found stemming from contact with the first patient.
The Florida patient was flying from Jedda, Saudia Arabia to London when he began to feel sick. From there, he took three connecting flights to Florida. Officials with the CDC said they were trying to track down and test some 500 passengers who flew with the unidentified patient in the United States.
CDC officials said they expected more cases to emerge in the U.S. The government agency's website is not recommending restricted travel to Saudi Arabia at this time. But health officials are encouraging Americans who go to the Middle Eastern country to wash their hands frequently and avoid touching their nose and eyes with unwashed hands.
Officials stress MERS is not easily transmitted. They say only those who live with or care for a MERS patient are at risk of becoming infected.
Individuals who start to feel sick 14 days after traveling to the Middle East are being urged to contact their health care providers immediately and to stay home.
As of May 12, there have been 538 laboratory confirmed cases of MERS globally. One hundred and forty-five of the patients have died. In Saudi Arabia, officials said 450 cases have been reported with 112 deaths since the virus was first recognized in 2012.
There is no vaccine or known treatment for the virus.
U.S. officials said they were working closely with international partners to identify additional MERS infections and contain spread of the virus.