Chickens may be silent carriers of bird flu

Jun 14 2006

Health officials are on alert again in Hong Kong following reports of a suspected case of bird flu just over the border with China in Shenzhen.

A truck driver is suspected of having contracted the deadly H5N1 virus in Shenzhen after developing a fever, back pains and a cough on June 3 and was admitted to hospital Friday.

He is said to be in a critical condition.

A six-member Hong Kong team comprising doctors, veterinarians and food-safety officials are now in Shenzhen to gather more information on the suspected case and are said to be very concerned.

Secretary for Health, Welfare & Food Dr. York Chow says if the case is confirmed live chicken imports will be suspended.

Health authorities are particularly concerned because the patient has no apparent history of close contact with poultry, similar to two previous cases in Shanghai and Guangdong and was not at any particular risk for the disease.

Shenzhen officials are only able to confirm that he visited a wet market before he became ill.

According to officials three initial tests on the truck driver by a local laboratory were positive for the H5N1 bird flu strain and the results of confirmatory tests by a Beijing laboratory are still pending.

The World Health Organization expects the case to be confirmed.

Dr. Chow has voiced the fear that the repeated cases on the mainland could indicate 'silent infections' amongst poultry, which might carry the virus while not showing symptoms.

Dr. Chow says Hong Kong is well equipped to detect and contain any outbreak of bird flu and there is no panic, but he advocates caution.

Hong Kong authorities are screening travelers arriving from Shenzhen by land for symptoms, and will intensify health inspections of poultry imported from the mainland.

The Hong Kong Department of Health will continue temperature checks at boundary checkpoints and all accidents and emergency wards will enhance surveillance to monitor cases of unknown sources of pneumonia.

A Yellow Alert is now in effect for infection control measures and people are urged to wash their hands before and after visiting public hospitals and to put on masks when necessary.

Experts believe the use of bad or substandard vaccines may have prevented birds from dying or falling sick, but may not stop them from getting infected and passing on the virus.

China had not as yet requested any assistance from the WHO.

The H5N1 virus first surfaced in Hong Kong in 1997, killing six of the 18 people infected, resulting in the culling of more than two million fowl but the H5N1 virus continued to circulate among birds in Asia, most recently among migratory species that carry the virus for long distances.

Scientists are worried the virus may mutate into a strain that is easily transmissible among humans, triggering a pandemic with the potential to kill millions.