(Adds details on patient status, airport advisories)
By Barbara Liston
ORLANDO May 14 (Reuters) - Two U.S. hospital workers who fell ill after contact with a patient suffering from Middle East Respiratory Syndrome (MERS) have tested negative for the often-deadly virus, a Florida health official said on Wednesday.
U.S. health officials had recently confirmed the country's first two cases of MERS, raising fears about the global spread of the virus, which has been responsible for a worsening outbreak in Saudi Arabia. More than 500 cases have been reported worldwide, with about 30 percent proving fatal.
The World Health Organization said on Wednesday that while its concern over MERS had significantly increased, the disease does not yet pose a global health emergency.
The patient with the second confirmed case of MERS on U.S. soil was hospitalized in Orlando, Florida after a 12-hour stay in the emergency department, potentially exposing healthcare workers to the virus.
He remained in an isolation room at Dr. P. Phillips Hospital and had been fever free for 24 hours, the hospital said on Wednesday.
Florida officials said they were monitoring a total of 20 healthcare workers who had been in contact with the patient. Test results for 19 of those workers were negative for MERS, according to Kevin Sherin, director of the Florida Department of Health in Orange County. The 20th worker, a doctor who had left for Canada, was still awaiting test results.
Scientists have few details on how the MERS virus spreads, but healthcare workers have proven particularly vulnerable because of their close contact with infected patients. Both U.S. cases involved healthcare workers who had spent time in Saudi hospitals that are treating people with MERS.
U.S. officials posted signs near security checkpoints and customs areas at leading airports such as Atlanta's Hartsfield-Jackson, Dallas/Fort Worth and New York's John F. Kennedy informing travelers about Middle East Respiratory Syndrome and advising them to take precautions such as washing their hands and report any flu-like symptoms.
The U.S. Centers for Disease Control and Prevention early this week issued a "Level 2" alert on travel to the Arabian Peninsula, advising passengers to pay extra attention to their health during and after their trip. The CDC did not recommend that people change their travel plans because of MERS.
Officials at major airlines such as Delta Air Lines and United Airlines said they are following CDC's guidelines but had no extra precautions for travelers.
According to a CDC analysis, New York City is expected to see the greatest influx of airline travelers from Saudi Arabia and the United Arab Emirates in May and June this year, at nearly 31,000 people. Washington, D.C. was second on the list at more than 24,500 passengers, followed by Los Angeles at more than 15,000. (Additional reporting by Karen Jacobs in Atlanta and Zachary Fagenson in Miami; Editing by Michele Gershberg, James Dalgleish and Bernadette Baum)