11 may have mystery disease in U.S.
ATLANTA, Georgia (CNN) -- The number of people in the United States suspected of having contracted a mysterious new pneumonia has grown to as many as 11, the Centers for Disease Control and Prevention said Wednesday.
The disease, a relatively unknown pneumonia called severe acute respiratory syndrome, or SARS, apparently started in Asia and has spread by infected travelers to Europe and Canada.
Health officials cautioned that SARS symptoms -- a fever above 100.4 degrees Fahrenheit (38 Celsius), a dry cough, and difficulty breathing -- are fairly common in late winter.
The most important risk factors are recent travel to Asia, close contact with someone who recently traveled to the area or close contact with a health care worker.
News of the illness and its symptoms prompted calls to health care workers nationwide this week, bringing the total number of suspected U.S. cases up from four on Monday.
The CDC said 40 people nationwide reported symptoms, but only 11 had the recent travel history to justify their placement into medical isolation.
"It is too early to tell if it's SARS," CDC Director Dr. Julie Gerberding said. "Anyone with pneumonia and a travel history is going to be under investigation. ... If you've not gone there, don't be concerned about it at this point."
Chinese authorities reported the same syndrome or a similar one in November in Guangdong Province. That outbreak peaked in mid-February after killing five of the 350 people infected.
The CDC lists another 219 SARS cases reported from February 1 to March 18. Cases have been reported in Singapore, Hong Kong, Taiwan, Thailand, Vietnam, Canada, Britain, Germany and Slovenia.
SARS is spread from person to person, but apparently only through close contact, possibly through "respiratory secretions and body fluids," the CDC said.
Nearly all the cases of documented transmission have occurred among family members and health workers involved in the direct care of people suspected of having SARS, according to health experts.
The Hong Kong Health Department reported Wednesday that seven of the people with SARS stayed at the same hotel in Kowloon, China, between February 12 and March 2.
Chinese health officials are trying to identify links among the seven. Two of them were known to have had close contact.
No new cases have been detected there since then and no hotel employees were infected, which is consistent with health officials' belief the virus is transmitted by close contact.
The hotel has closed off the floor the infected people used and it is being disinfected as a precaution, Hong Kong health officials said.
The CDC, which has been issuing health alerts to passengers arriving in the United States on direct flights from Hong Kong, will expand that to include people arriving via indirect routes from areas that have reported outbreaks and to people traveling on cruise ships in those areas, Gerberding said.
Earlier Wednesday, doctors at the Prince of Wales Hospital in Hong Kong said the same class of virus that causes mumps and measles might be behind SARS.
Doctors at the World Health Organization and the CDC said Tuesday preliminary results of tests indicated the same link between SARS and the virus class known as paramyxovirus.
Scientists stress that even if SARS patients have been infected with this class of virus, that does not necessarily mean it is the virus causing the atypical pneumonia. The patients also could be infected with another organism that might be the culprit.
Four people have died from SARS and another 215 people have been diagnosed with it, according to the WHO Web site.
The bulk of those cases are in Hong Kong and Hanoi, where at least 111 people are suffering with SARS.
The earlier deaths and other cases in China are not included pending confirmation they were caused by the same disease.
Paramyxoviruses cause several respiratory diseases in humans and animals. One of the viruses, parainfluenza, infects almost all children before they reach their 5th birthday, causing illnesses ranging from colds to pneumonia, according to the National Institutes of Health.