Update, 6 January, 8:55 a.m.: Wuhan health authorities reported yesterday that severe acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS) have now been ruled out as the cause of unexplained viral pneumonia that has sickened 59 people, according to the latest tally. No deaths have resulted so far, though some people remain critically ill. “The epidemiological association of these unexplained pneumonia cases with the wet market selling not just seafood, but also some game-food animals strongly suggests that this is a novel microbe jumping from animal to human," says Yuen Kwok-Yung, a microbiologist at the University of Hong Kong. Given China's advances in epidemiology, infection control, and laboratory diagnostic capabilities since the SARS outbreak in Asia in 2003, Yuen says "It is highly unlikely that this outbreak will lead to a major [SARS-like] epidemic, though we cannot be complacent!" Screening in Hong Kong has turned up more than a dozen travelers from Wuhan suffering from pneumonialike symptoms, although it’s not clear they are related; Singapore found one such case.
Stoking fears that a novel virus may have begun to infect people, health authorities in the central Chinese city of Wuhan late on Friday local time announced they have documented 44 unusual cases of pneumonia—a sharp jump from their initial report of 27 cases on 31 December 2019. Although the city is being praised for quickly sharing information, infectious disease specialists around the world are eager to get more details on the mysterious pathogen and the disease it produces in patients. In today’s report, Wuhan officials ruled out influenza, avian flu, and adenovirus; they call the disease a “viral pneumonia of unknown cause.”
Hints of trouble first surfaced publicly on 30 December, when a directive from the Wuhan Municipal Health Commission asking hospitals to report unusual cases of pneumonia was reported by local media. The next day, the commission posted a notice in Chinese on its website stating that a number of local hospitals had reported cases of pneumonia linked to the wholesale Huanan Seafood Market. The commission had turned up 27 cases in the city of 11 million, 690 kilometers west of Shanghai. Seven of the patients were in serious condition, two had recovered and were nearing discharge, and the remaining number were stable. All patients were isolated and their close contacts were under surveillance, the notice stated.
At that time, no human-to-human transmission had been identified. The commission updated that information today, saying 11 of the 44 cases are considered serious. The new patients are also in isolation. An additional 121 close contacts of patients are under surveillance, although the commission has so far ruled out human-to-human transmission.