Lockdown measures have been stepped up in China to contain a fast-spreading deadly virus, with three cities under travel restrictions as more cases emerge around the world.
The World Health Organisation has described the lockdown of millions of Chinese over the coronavirus (2019-nCoV) as “unprecedented” but said it was too early to declare a global emergency.
It comes amid preliminary research suggesting humans might have contracted the respiratory illness from snakes which, in turn, might have become infected hunting bats in the wild.
A new report in the Journal of Medical Virology said an analysis of the virus’s genetics showed it was closely related to two types of SARS illness originating from bats and might have spread from bats to snakes – in particular the Chinese krait and Chinese cobra – and mutated and jumped from there to humans.
Snakes are apparently sold at the seafood market in Wuhan, a city of 11 million people in central China that is the epicentre of the outbreak, which had killed 17 people and infected more than 600 by late Thursday.
The first people to fall ill were believed to have been staff or customers at the market ,where a range of animal products and illegal wildlife are sold, as well as seafood.
However, Chinese government medical adviser Zhong Nanshan also identified badgers and rats as possible sources.
With no known cure, a race to produce a coronavirus vaccine has begun in earnest involving three research teams, including scientists at the University of Queensland.
Health officials fear the transmission rate of the SARS-like infection will accelerate as hundreds of millions of Chinese travel at home and abroad during week-long holidays for the Lunar New Year. It begins on Saturday.
Airports around the world have begun screening as cases of the virus were confirmed in Thailand (four), Vietnam (two), and one each in Singapore, Japan, South Korea, Taiwan and the US. Scotland is assessing four potential cases.
A Queensland man who fell ill after returning to Australia from Wuhan had not contracted the virus, health authorities confirmed.
Singapore confirmed its first case was a Wuhan man who arrived in the country on January 20. He is in isolation in hospital.
One of his travelling companions is also in hospital as a suspected case.
Vietnam’s health ministry said on Thursday two Chinese citizens in the south-east Asian country had tested positive for coronavirus. They were said to be in a “good condition”.
Most transport in Wuhan has been cancelled and people ordered not to leave the city of 11 million people.
Neighbouring Huanggang, a city of about 7 million, has announced a similar lockdown, while the city of Ezhou has restricted its public transport.
As Wuhan slipped into isolation, residents thronged into hospitals for checks and scrambled for supplies, clearing supermarket shelves and queuing for petrol.
The WHO’s representative in Beijing, Gauden Galea, said the lockdown of millions of people was unprecedented in public health history.
“Make no mistake, though, this is an emergency in China. But it has not yet become a global health emergency. It may yet become one,” WHO chief Tedros Adhanom Ghebreyesus said after a meeting of experts in Geneva.
— World Health Organization (WHO) (@WHO) January 23, 2020
Other cities were also moving to restrict movement and contact.
China’s Education Ministry said schools should not hold large events or exams.
The capital cancelled major public events, including two Lunar New Year temple fairs, the state-run Beijing News said.
Hong Kong, which has two confirmed cases, is turning two holiday camps into quarantine stations. Taiwan has banned anyone from Wuhan from the island.
Some experts, including Australia’s chief medical officer, believe the virus is not as dangerous as previous coronaviruses such as SARS and Middle East Respiratory Syndrome.
“The early evidence at this stage would suggest it’s not as severe,” Professor Brendan Murphy said.
In a report on Wednesday, Imperial College London said it estimated a total of 4000 cases of the coronavirus in Wuhan alone as of January 18. The rate was based on the number of cases reported in China and elsewhere.
In contrast with its secrecy over the 2002-03 SARS outbreak, which killed nearly 800 people, China’s communist government has provided regular updates to avoid panic ahead of the holidays.