Hong Kong diners urged to avoid raw oysters as more food poisoning cases found

Hong Kong health authorities have urged diners not to eat raw oysters for the time being after another seven people in two groups suffered norovirus-related food poisoning from consuming the seafood. The Centre for Health Protection said on Thursday that six women and a man, aged between 24 and 45, came down with diarrhoea, abdominal pain, vomiting and fever around 28 to 36 hours after dining at a branch of the O Delice! French bistro chain in Tsim Sha Tsui on January 31 and February 1. Three sought medical advice but none required hospitalisation. All are in a stable condition. Investigations found the affected diners at the outlet in The ONE shopping centre had consumed raw oysters supplied by Jeton International Food and 88 Investment Holdings Limited. The two companies were ordered to suspend the sale and supply of raw oysters on February 6, after being linked to other cases. The restaurant chain’s outlet at the New Town Plaza shopping centre in Sha Tin was also involved in similar incidents recently, when four diners fell ill after eating raw oysters on January 31 and February 1. One person was hospitalised, with stool samples confirming norovirus infection. Centre controller Edwin Tsui Lok‑kin said food poisoning cases had risen sharply, from a weekly average of one in late December to four per week in January. Between January 18 and Thursday, the centre recorded 45 cases affecting 135 people, with nearly 87 per cent linked to norovirus. “As oysters feed by filtering a large volume of seawater, pathogens can accumulate in them if they are grown in or harvested from contaminated water. Raw or undercooked oysters are considered a high-risk food,” Tsui warned. “During Lunar New Year, people usually gather for meals with relatives and friends. I particularly remind the public that only thoroughly cooked food, especially shellfish, should be consumed, whether dining at home or in restaurants, to avoid contracting enteric diseases.” Tsui said norovirus was highly contagious and could be spread through person-to-person contact or in a vomit-contaminated environment. He said norovirus was also one of the primary causes of acute gastroenteritis. Tsui said norovirus could not be killed by alcoholic beverages, lemon juice or wasabi. He added that when cooking oysters in hotpot or on the grill, they had to be thoroughly cooked to minimise the risk of norovirus infection. University of Hong Kong microbiologist Yuen Kwok‑yung said oysters could concentrate viruses in their bodies. The rate could be up to 99 times that of the surrounding contaminated seawater. He stressed that oysters were safe if thoroughly cooked and cross‑contamination was controlled, adding imports should not be banned. “Norovirus cannot be killed by alcohol,” Yuen said. “It is wrong to claim that handwashing with sanitiser or plain water can eliminate it – neither is effective against norovirus.”