An unidentified form of pneumonia has broken out in the central Chinese city of Wuhan, prompting authorities to quarantine those infected and raise hospital alerts. Wuhan’s health bureau announced Sunday that close to 60 patients have been diagnosed with the virus, and neighboring Hong Kong has announced suspected cases. (A suspected case in Singapore turned out to be a false alarm.)
The mysterious strain has been linked to a seafood market which has been closed for sanitation since Jan. 1. Medical experts are attempting to identify the illness. While they say it is unlikely that this new strain of pneumonia could cause a repeat of 2003’s deadly SARS outbreak in 2003, which killed hundreds in mainland China and spread as far as the U.S. and Canada, they stress that vigilance should not be relaxed.
Here’s what to know about the virus.
How serious is the pneumonia outbreak?
According to Wuhan’s health bureau, 59 patients have been diagnosed with the virus, including seven in critical condition as of Sunday. Some of the patients operated stalls at the seafood market. All of the patients are in quarantine, and 163 people who had been in close contact with them have been placed under medical observation. The World Health Organization says symptoms include fever and difficulty breathing.
How fast is it spreading?
The first case was discovered in Wuhan on Dec. 12, the city’s health bureau says. On Sunday, authorities in Hong Kong reported that nine more patients were found to have fever or respiratory symptoms after returning from Wuhan, bringing the number of cases in the city to 17.
How are authorities outside China responding?
Governments are stepping up precautionary measures in the wake of the outbreak. Hong Kong’s Hospital Authority has imposed shorter visiting hours at hospitals and is requiring all visitors to wear face masks. The city has also enhanced the airport’s thermal imaging system to screen the temperatures of travelers coming from Wuhan. Additional manpower has been assigned to the train station that connects the city to mainland China to carry out temperature checks.
Singapore’s Ministry of Health announced Thursday that it is implementing temperature screenings for travelers arriving on flights from Wuhan. Taiwan’s Centers for Disease Control has asked doctors and airport quarantine officials to notify the bureau of patients who have traveled to Wuhan and exhibit any symptoms.
The World Health Organization (WHO) says it is monitoring the situation and “in close contact with national authorities in China.”
Could this evolve into a large-scale outbreak like SARS?
Wuhan’s health bureau said that the viral pneumonia is not SARS, MERS (Middle East Respiratory Syndrome) or bird flu. It also said there is no evidence of human-to-human transmission, but medical experts have expressed their reservations. “They did not exclude this possibility completely,” Leo Poon, a virologist and SARS expert at the University of Hong Kong, tells TIME.
Still, the fact that there have not been any deaths so far — 10% of those who contracted SARS in 2003 died — is reason to believe that the outbreak will not take a more serious turn, Poon adds.
Yuen Kwok-yung, a microbiologist at the University of Hong Kong, says there are marked advances in scientific research and laboratory diagnostic capabilities since the SARS outbreak over a decade ago.
“It is highly unlikely that this will lead to a major 2003-like epidemic,” Yuen says, “though we cannot be complacent.”