China announced on Sunday that an unknown form of viral pneumonia has broken out in the central city of Wuhan and has so far infected almost 60 people.
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The outbreak, which has prompted authorities to quarantine affected individuals, has led to online speculation about a resurgence of the SARS virus.
However, the Wuhan health commission has said the pneumonia outbreak is not like the highly contagious SARS virus and has also ruled out several other viral infections. Wuhan police said on Wednesday that eight people had been punished for publishing or forwarding false information on the internet without verification.
We have excluded several hypotheses, in particular the fact that it is a flu, an avian flu, an adenovirus, respiratory syndrome severe acute (SARS) or Middle East Respiratory Syndrome (MERS)."
Wuhan Health Bureau
The first case of infection was first reported last week in Wuhan, which has a population of more than 11 million. On Sunday, neighboring Hong Kong reported more suspected cases, as nine people returning from Wuhan were found to have fever and respiratory symptoms.
The unknown strain has been linked to a seafood market
The unidentified strain has been linked to a seafood market in Wuhan, that has since been closed for disinfection. Medical experts are trying to identify the strain, but in the meantime, they say it is probably not going to lead to an outbreak on the same scale as the 2003 SARS epidemic that claimed the lives of hundreds in China and spread as far as the US and Canada.
However, vigilance should not be relaxed, they warn. According to the Wuhan health commission, seven of the 59 patients diagnosed with the virus have been in a critical condition since Sunday, although none have yet died. All of the patients have been quarantined, and 163 people who had been in close contact with them have been placed under observation.
No evidence so far of human-to-human transmission
The Wuhan bureau has said there is no evidence so far of human-to-human transmission, and the World Health Organization (WHO) has said: “the reported link to a wholesale fish and live animal market could indicate an exposure link to animals.”
However, virology experts are not entirely convinced that human-to-human transmission can be ruled out: “They did not exclude this possibility completely,” says Leo Poon, a virologist and SARS expert at the University of Hong Kong.
Strengthening precautionary measures
Governments are now tightening up on precautionary measures, with Hong Kong’s Hospital authority limiting hospital visiting hours and making it mandatory for visitors to wear facemasks. Hong Kong airport’s thermal imaging system has been enhanced to screen people coming in from Wuhan, and temperature checks at the city’s train station have been stepped up.
On Thursday, Singapore’s Ministry of Health announced that it would also be temperature screening people arriving on flights from Wuhan, while Taiwan’s Centers for Disease Control has requested that doctors and airport quarantine staff report any cases of symptoms among people who have traveled to Wuhan.
The WHO has said it is closely monitoring the situation and is in close contact with Chinese authorities.
"There are many potential causes of viral pneumonia, many of which are more common than severe acute respiratory syndrome coronavirus," said a spokesman last week. "WHO is closely monitoring this event and will share more details as we have them."
What is the probability of a 2003-like SARS epidemic?
The WHO criticized China for its under-reporting of SARS cases following the outbreak in 2003 that killed 349 people in mainland China and 299 in Hong Kong.
However, Poon says the fact that this new, unidentified virus has not caused any deaths so far, is reason to believe that the outbreak will not take a more serious turn.
Microbiologist at the University of Hong Kong, Yuen Kwok-yung, says there have been significant 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, though we cannot be complacent."
Yuen Kwok-yung, University of Hong Kong
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