HK fears healthy-looking but H5N1 infected chickens

HONG KONG, June 14 (Reuters) Hong Kong is worried about healthy-looking chickens in China that are carrying the H5N1 bird flu virus as they are capable of silently infecting people, the city's health minister said today.

The comments from Health Minister York Chow come as health authorities in mainland China are trying to confirm if a 31-year-old truck driver in Shenzhen, a bustling city just across the border from Hong Kong, may be infected by the virus.

''We are most concerned about chickens that don't show symptoms but which carry the virus and are able to infect people,'' Chow told reporters in Hong Kong.

If confirmed, the truck driver, who is seriously ill, would be the 19th person to be infected with the disease in China over the past year. Twelve of them have died so far.

Although China has reported about 40 outbreaks of bird flu in birds across a dozen provinces over the past year, many of its human cases have occurred in places where there were no known outbreaks of the disease in poultry.

This has stumped experts because in most documented infections elsewhere, victims were all infected after direct contact with sick birds.

In this latest suspected case, Chow said the truck driver had gone shopping in a wet market which sold live poultry and eaten a chicken before he fell ill, but he was not known to have had any close contact with poultry.

Chow said he was most concerned about backyard chickens in China, which make up about 60 percent of its total chicken population of 14 billion.

''There might be poultry that are carrying the virus and running around and do not have any symptoms. If humans get in touch with them, they may actually get infected without us knowing exactly the source of infection,'' he said.

Experts say the use of bad or substandard vaccines may prevent birds from dying or even falling sick, but not stop them from getting infected and shedding the virus in their stool. This problem, known as ''masking'', has also been observed in Indonesia, where the H5N1 virus has killed at least 37 people.

REUTERS CH VV1641