The coronavirus that has recently emerged in the Middle East and killed one person has been confirmed as a different bug from the one that caused the deadly Sars epidemic in 2003.
"It is a new coronavirus, but it is not the Sars virus," World Health Organisation director general Margaret Chan Fung Fu-chun said yesterday.
Separately, doctors yesterday said five people at a Danish hospital are suffering from a typical influenza strain and not the new Sars-like illness as feared.
The five, three adults and two children, tested positive for Influenza B, , the Odense University Hospital said, and were recovering. They were to be released later in the day.
The new Sars-like virus, which causes a serious respiratory infection, took the life of a 60-year-old Saudi Arabian man earlier this year, and a 49-year-old Qatari man is in critical condition after he visited the Saudi kingdom. It sparked fears of a recurrence of the Sars epidemic - also caused by a coronavirus - that killed 774 worldwide including 299 in Hong Kong. But the likelihood was dismissed by the WHO and Hong Kong's Health Department.
Chan said the WHO had so far been unable to evaluate the disease fully, as it could gain only limited data from the two known cases. "The only relation between the cases is one patient was from Saudi Arabia, and the other had visited Saudi Arabia," she said.
Dr Thomas Tsang Ho-fai, controller of Hong Kong's Centre for Health Protection, warned the new virus could still cause a serious outbreak, even though gene sequencing had proved it was different from Sars.
The virus will be listed as a notifiable disease under Hong Kong law in the next few days.
"It is a precaution to give the government legal grounds to implement infection control measures, such as the isolation of an infected person, tracking anyone with whom the patient had close contact, and quarantining hotels or apartments if necessary in case there is an outbreak," Tsang said.
According to the gene sequencing analysis by British health authorities, the new virus belongs to the 2C group of coronaviruses. Sars is in the 2B group.
"Being in a different group means the two viruses are totally unlike in their process of genetic mutation. Most coronaviruses, which are a big family, are mild such as the common cold. Sars was a rare exception," he said.
"But it does not mean the new disease is not serious. The risk it poses to Hong Kong still cannot be ruled out … we still need more information about its nature."
The government will maintain close contact with the Saudi consulate. Saudi Arabia said it had taken precautions to prevent disease spreading next month, when it expects over two million Muslims to flock to the annual Haj pilgrimage, then return home.
"The situation is dynamic and more developments may take place in the coming days and weeks as more investigation findings come to light," he said.
Xinhua, Agence France-Presse