The University of Hong Kong's influenza virus surveillance programme found five samples taken from pigs at the Sheung Shui Slaughterhouse on December 17 tested positive for the human swine influenza virus, the Food & Environmental Hygiene Department said today.

This is the third time the programme uncovered positive samples. No gene reassortment has occurred and the virus remained genetically similar to the human swine flu viruses regularly found in people. The flu virus is believed to have been transmitted from people to pigs.

The concerned samples were taken from pigs imported from the Mainland. The department informed the Mainland authorities, and they have strengthened monitoring of registered farms that supply live pigs to Hong Kong.

The World Health Organisation, World Organisation for Animal Health, Food & Agriculture Organisation of the United Nations and World Trade Organisation state that pork and pork products which are handled properly and thoroughly cooked are not a source of human swine flu infection.

Safe to eat

It is safe to eat pork and pork products that are cooked to an internal temperature of 70 degrees Celsius or above.

All imported live pigs from the Mainland should come from registered farms and have health certificates issued by the Mainland authorities. The Food & Environmental Hygiene Department inspects the certificates and the imported pigs' health conditions at the boundary control point.

Only pigs which pass the inspections before and after they are killed at the slaughterhouses can be supplied to the market and sold for consumption.