Epidemiological data: Shellfish have been associated with food-borne viral infection throughout the world. In 1991 almost 300 000 people in Shanghai contracted hepatitis and nine died after consuming cockles contaminated with hepatitis A virus (Tang et al. 1991).
Hepatitis A virus has also been linked to shellfish-associated gastroenteritis in Australia (Table 4.8). The first reported case of hepatitis A virus from shellfish in Australia was attributed to under-cooked mussels from contaminated waters in Victoria. Seven out of the ten consumers who ate the mussels developed symptoms of hepatitis A (Locarnini & Gust 1978).
The largest outbreak of hepatitis A in Australia occurred during 1996–97 following consumption of oysters harvested from the Wallis Lake region, New South Wales, Australia (Communicable Disease Intelligence 1997) when 444 people were affected and one died.
Table 4.8: Recent outbreaks of hepatitis shellfish-associated food poisoning in Australia
Year
Seafood
Growing area
Cases (deaths)
1997
Oysters
Wallis lake, NSW
466 (1)
1997
Prawns
Imported product
17
Source: C Dalton, Hunter Public Health Unit, personal communication.