Aug 6, 2004 (CIDRAP News) – South Africa has stopped all poultry exports and plans to slaughter 6,000 ostriches on two farms because of an avian influenza outbreak, but the flu is a different strain from the one that has plagued Southeast Asia this year, according to news services.

Reports by Reuters and other services today listed the strain as H5N2. The virus that swept through Southeast Asia early this year and has recurred in several countries this summer is H5N1.

The South African outbreak began about 3 weeks ago and has killed 2,000 ostriches on two farms in the Eastern Cape province, according to an SABC (South African Broadcasting Corp.) News report today. Authorities planned to kill the remaining 6,000 ostriches on the two farms, and farms in the surrounding area were under quarantine, the report said.

The SABC story described the H5N2 virus found in the ostriches as "extremely infectious but not transferable to human beings and poultry." The H5N1 strain in Asia earlier this year caused at least 34 human cases and killed 24 people.

Reuters quoted the South Africa Department of Agriculture today as saying it has "stopped exports of poultry and poultry products from South Africa until the outbreak has been dealt with successfully."

A note posted yesterday on ProMED-mail, the online reporting system of the International Society for Infectious Diseases, said avian flu outbreaks in ostriches don"e;t necessarily affect poultry. The note, by a ProMed-mail moderator, said various low-pathogenic strains of avian flu infected ostriches in South Africa in 1991, 1992, 1994 and 1995. The first report of highly pathogenic avian flu in ostriches came from Italy in 2000, the note said.

In other recent developments, a new avian flu outbreak was reported in Vietnam this week, according to Xinhua, China"e;s state news service. The Aug 3 report said the disease cropped up on a farm in the southern city of Can Tho. Including that outbreak, southern Vietnam has had outbreaks in 11 areas since late June, leading to the death of 63,000 chickens by disease or culling, the story said.