Manila - The Philippines' agriculture department has ordered the extermination of some 6,000 pigs afflicted with the Ebola Reston virus, a senior official said Tuesday.

Davinio Catbagan, director of the Bureau of Animal Industry, said the culling of the hogs in a farm in Pandi town, Bulacan province, 35 kilometres north of Manila, will be done within two to three days.

"After we dispose the 6,000 hogs, which were positive of the Ebola Reston virus in Pandi, we will start inspecting other farms not only in Bulacan but also in nearby provinces," he said.

Agriculture Secretary Arthur Yap said the 6,000 hogs to be killed represented only 0.5 per cent of the 13 million pigs raised throughout the country.

Experts from various international organizations, including the United Nations Food and Agriculture Organization (FAO) and the World Health Organization (WHO), are helping the Philippines address the problem.

The Ebola Reston virus was first detected late last year at several hog farms in three northern provinces and Manila.

At least five farm workers have been found to have been infected with the virus but all of them have remained healthy during the past 12 months, according to Health Secretary Francisco Duque.

WHO noted that it was the first time that the virus has been found outside monkeys and the first time ever worldwide that it has been found in swine.

Ebola Reston is one of five species of the virus. It can infect humans but without causing serious illness or death, unlike the Zaire, Bundibugyo and Sudan strains, according to FAO.

The Ebola Reston strain was discovered in the United States in 1989 in association with an outbreak of viral hemorrhagic fever among monkeys imported from the Philippines to Reston, Virginia. The virus was found among Philippine monkeys in the US again in 1990 and 1996. (dpa)