Hong Kong confirmed on 3 November that a dead grey heron (a migratory bird) was tested positive for H5N1 virus. Grey heron is an abundant winter visitor to Hong Kong but not a resident species. All poultry farms within 5 kilometers where the heron was found have been checked and no unusual mortality or illness detected. There were 7 persons who had contact with the dead bird. All of them are in good health. The Centre for Health Protection is monitoring their medical conditions.

An intensive surveillance system has been in place on all poultry farms, wholesale and retail bird markets in Hong Kong. Since January 2004, 1,200 dead birds and 12,600 environmental swabs have been tested and no evidence of H5N1 has been detected. In addition, more than 2,200 samples have been tested as part of the wild bird surveillance programme. The only 2 cases of H5N1 infection detected were the peregrine falcon (a migratory bird) reported on 19 January 2004 and the grey heron this month. 1,600 pet birds have been tested and all results were negative.

Please refer to OIE report http://www.oie.int/eng/info/hebdo/aIS_20.htm#Sec7 and CHP webpage http://www.chp.gov.hk/content.asp?lang=en&info_id=1759 for details.

The Ministry of Public Health in Thailand confirmed on 25 October an additional fatal case of human infection of H5N1. This was a 14-year-old girl from Sukhothai Province. Chickens at her household died in late September before her onset of illness. The girl’s death brings the total in Thailand to 17 cases, of which 12 have been fatal. The number of case in Vietnam remained unchanged, with a total of 27 cases leading to 20 deaths.

Poultry outbreaks of avian influenza continued to be reported in Thailand. Since 1 October 2004, Thailand authority has been conducting active surveillance nationwide so that all suspect flocks can be immediately destroyed regardless laboratory confirmed. Since 1 October, there were 301 outbreaks reported with 40,000 birds dead and 294,000 birds destroyed.

In Malaysia, culling of susceptible birds within 1 kilometer radius of the infected foci and disinfection were completed on 10 October. As of 31 October (21 days after completion of operation), no new cases of avian influenza had been detected. There was no new report on poultry outbreak in Indonesia.

On 29 October, WHO reported that a study describing domestic ducks infected with 2004 H5N1 viruses are shedding more virus for longer periods, when compared with infections by viruses from 2003. It also indicated that the recent H5N1 viruses survive several days longer in the environment. In addition, the quantities of virus excreted by healthy-looking ducks approach those excreted by diseased chickens, and suggested that domestic ducks can act as silent reservoir for H5N1 virus. The altered role of domestic ducks in the transmission cycle of H5N1 raised public health concern for those affected countries to pay special precaution when handling domestic ducks. OIE and FAO are formulating a long-term strategy for bringing the current outbreaks in poultry under control. Details can be obtained from WHO website http://www.who.int/csr/don/2004_10_29/en/.

The CHP has established a programme of human influenza surveillance 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. The CHP will continue to liaise with WHO and authorities in affected countries for further information and will inform the public of any important updates.