Key message: Viruses are composed of genetic material (i.e. DNA or RNA) in a protein and/or membranous outer layer. The virus can be spread by various means in addition to contaminated food, such as directly or indirectly through the faeces or vomit of patients. Although the amounts of viruses do not increase in contaminated food, most viruses can transmit diseases in small numbers (10 to 100 virions).
Common viruses that cause food poisoning
| Virus | Usually found | Common sources of food poisoning |
|---|---|---|
| Avian Influenza | Poultry | Undercooked poultry and eggs |
| Hepatitis A | Seafood | Raw or undercooked shellfish, or fresh produce irrigated with contaminated water |
| Hepatitis E | Seafood and Meat | Contaminated food (such as shellfish), raw or undercooked meat (such as pork liver) |
| Norovirus | Shellfish | Shellfish (especially oysters), undercooked vegetables, salads and ice cubes |
African Swine Fever
African swine fever is a severe viral disease of pigs that is highly contagious but does not infect humans and poses no food safety risk. According to the World Organization for Animal Health, African swine fever does not pose a threat to human health.
To reduce the risk of ASF intrusion into local pig population, control and surveillance at source are of utmost importance. All imported pigs delivered to slaughterhouses must come from registered pig farms supplying Hong Kong. Pigs have to be quarantined to ensure no signs of African swine fever before they are released. In addition, all pigs must be accompanied by a valid health certificate issued by the Mainland Customs.