Bird flu death sparks worries
Health authorities on the mainland have urged the public not to panic after a man who contracted the bird flu virus died at the weekend.
But Hong Kong medical experts said the fact that the virus had been transmitted from a bird to a person was a cause for serious concern, and called for careful handling.
The man, surnamed Chen, died on Saturday in Shenzhen, where thousands of chickens have been culled after three birds tested positive for the H5N1 bird flu virus in mid-December.
The Shenzhen Disease Control Centre confirmed that Chen, a bus driver, had contracted H5N1 from poultry, but said it was still trying to discover how he acquired the virus.
The centre said the virus had mutated in normal, natural ways, but it had not become transmissible between humans. Some genetic mutations make the disease more deadly or easily transmissible.
Chen is the mainland's first reported human case of the deadly disease in 18 months.
The Shenzhen centre sought to reassure the public, issuing a statement saying 'the virus cannot spread among people' and 'there is no need for Shenzhen citizens to panic', Xinhua reported.
But Professor Ho Pak-leung, a microbiologist at the University of Hong Kong, said there was a danger that the virus could be transmitted from wild birds to people.
'The virus was evidently virulent since it killed the victim, who was a young man, in a short period of time,' he said.
The same strain of the virus has been found in wild birds in Hong Kong, Ho said.
The H5N1 virus is fatal in humans in about 60 per cent of cases, but so far there is no sign that it has been transmitted among people, he said.
Ho said extra care should be taken when handling frozen chicken - it should be thoroughly cooked, and hands must be washed afterwards.
Frozen chicken should be properly defrosted before cooking, to ensure the heat penetrates the meat. Heating chicken at 70 degrees Celsius for three minutes is enough to kill the virus, health officials say.
Chen developed a fever on December 21 and was taken to hospital four days later, where he was diagnosed with severe pneumonia, the Shenzhen health department said.
The 39-year-old had apparently had no direct contact with poultry in the month before he fell ill, nor had he left the city, the department said.
Hong Kong's Centre for Health Protection said the viral strain that caused Chen's death was very similar to one recently found in wild birds in Hong Kong. Genetic analysis found that the virus can be treated by amantadine, a common antiviral drug.
Imports of frozen chickens and all other poultry products from a Shenzhen supplier were banned in Hong Kong for 21 days from Sunday, after Chen's death.
The embargoed factory is located near Chen's home. It is public health policy to declare such an 'import control zone' inside a 13-kilometre radius of a patient's home.