The Hong Kong Agriculture, Fisheries and Conservation Department (AFCD) has confirmed that a dead Grey Heron found in Lok Ma Chau area was tested positive for H5N1 virus.
A Government spokesman said: "The dead bird, which was first found by a worker of the Lok Ma Chau Spur Line project within the restricted area of Lok Ma Chau, was handed to AFCD for diagnostic testing on November 1. Swab and tissue samples from the bird were confirmed positive for H5N1 avian influenza virus today".
In response, the Government has stepped up monitoring of biosecurity measures at chicken farms, the inspection of poultry stalls in retail markets and the surveillance of wild birds at recreational parks. The Centre for Health Protection (CHP) has also initiated its surveillance programme for public health monitoring.
"All poultry farms in the vicinity of where the dead bird was found, totalling 37, have been inspected by AFCD staff. There was no abnormal mortality and the chickens showed no symptoms of avian influenza. Farmers have been alerted to pay special attention to their bird-proofing facilities and to strictly implement bio-security measures," the spokesman said.
"As a precautionary measure, the AFCD will step up its farm inspection programme and wild bird surveillance programme at recreational parks during the next few days.
"The Food and Environmental Hygiene Department will also continue to closely monitor the situation at the retail markets."
The spokesman said the CHP was monitoring the health conditions of the seven persons who had contact with the dead bird.
"As the CHP has taken immediate and prompt actions to initiate its surveillance programme on public health, and made all necessary arrangements for those in contact with the infected dead bird, it is unlikely that the virus has been able to spread in the community. Therefore, we believe that there is no immediate threat to the public health," he said.
Members of the public are reminded to observe good personal hygiene. They should avoid contact with wild birds and live poultry and clean their hands thoroughly after any contact with them.
Since 1998, Hong Kong has put in place a comprehensive surveillance programme which enables the relevant authorities to monitor human influenza activity and detect the presence of avian influenza viruses in the environment.
On human influenza surveillance, the CHP has initiated a programme that covers a network of clinics, hospitals and laboratories in the public and private sectors, thus enabling the Centre to monitor the disease trend and circulating influenza viruses.
On avian influenza surveillance, a comprehensive surveillance programme targeted at poultry at all levels from farms, import, wholesale market and retail outlets has been implemented. At the farm level, all chickens available in the market must be vaccinated against H5 avian influenza. Stringent bio-security measures, including the requirement for all chicken farms to be bird-proof, have been imposed to prevent the introduction of viruses by wild birds.
For imported chickens, they must come from registered farms recognized by the Mainland authority and vaccinated against the H5 avian influenza. For each consignment of imported chickens, a health certificate is required from the relevant authority. The import control programme also includes testing of the antibody level of imported chickens, dead and sick bird monitoring and random screening testing for H5 virus as appropriate.
At the retail level, market rest days have been introduced to reduce the viral load there, if any. Each month, there are two rest days at the retail outlets. Trading activities must cease on the rest days and all live poultry in the retail outlets must be slaughtered and the premises must be thoroughly cleansed and disinfected.
In 2003, the Government has extended the surveillance programme to wild birds in recreational parks so as to ensure timely detection of the presence of any avian influenza viruses in our environment and possible re-assortment of the viruses. Under this surveillance programme, more than 2,000 samples have been tested since January 2004.
The Grey Heron (Ardea cinerea) is an abundant winter visitor but scarce summer visitor in Hong Kong. It is not a resident species in Hong Kong.