Nov 9, 2007 (CIDRAP News) – Officials in Vietnam recently reported H5N1 avian influenza outbreaks at farms in two more provinces, bringing to six the number of provinces hit by the virus since early October.

On Nov 7, the agriculture ministry confirmed the H5N1 virus in samples from a flock of 2-month-old ducks at a farm in Ha Nam province in the northern part of the country, Reuters reported yesterday. The ministry"e;s report also said the virus was found in two dead chickens that were dumped in a river in the province.

Today the agriculture ministry reported another H5N1 outbreak in Ben Tre province, in southern Vietnam, China"e;s state news agency Xinhua, reported. The outbreak killed half of a 60-bird flock of 2-month-old ducks, the report said.

Recent outbreaks have also been reported in Cao Bang and Nam Dinh in the north, Quang Tri in the central part of the country, and Tra Vinh in southern Vietnam, according to previous reports from the World Organization for Animal Health (OIE). All involved unvaccinated ducks.

In other developments, a United Nations (UN) official today cautioned Asia to be watchful for a sharp rise in avian flu outbreaks as winter approaches, the Associated Press (AP) reported.

"The northern winter seems to be a time when the risk of the disease in poultry increases, and it"e;s partly to do with the facts that this virus quite likes the cold weather," David Nabarro, the UN"e;s coordinator for avian flu, told the AP.

He said birds migrating from Asia to the south and west in the winter could carry the disease to new areas, the AP reported.

Vietnam has not reported a human H5N1 case since August. With 100 cases and 46 deaths, the country is the world"e;s second hardest hit country by avian flu, behind Indonesia.