The number of outbreaks almost doubled in Hong Kong in 2023 compared to the year before.

Officials reviewed food poisoning outbreaks related to food premises and businesses reported to the Centre for Food Safety (CFS) of the Food and Environmental Hygiene Department (FEHD) in 2023.

CFS and the Department of Health are responsible for investigating and controlling outbreaks related to local food premises.

This past year, the Department of Health referred 219 food poisoning outbreaks to CFS, which affected 838 people. This is back to levels similar to 2020 and before the COVID-19 pandemic. In 2022, CFS received 117 foodborne outbreak referrals, which affected 500 people.

Bacteria behind most incidents
In 2023, bacterial foodborne agents remained the top cause of food poisoning cases. The top three bacteria were Vibrio parahaemolyticus, Salmonella, and Clostridium perfringens.

Viral cases accounted for a quarter of outbreaks, all of which were related to norovirus. Other outbreaks were linked to toxins.

The three most frequently identified contributing factors were the consumption of raw food, contamination by raw food, and improper food storage temperature.

Eight cases involved unpasteurized eggs in desserts in the second half of 2023. CFS investigations found that some businesses used unpasteurized eggs when making desserts, and others kept desserts at inappropriate temperatures.

Eggs are a component of many desserts, including cheesecakes, soufflé, tiramisu, and mousse. Some chefs might not cook desserts that include eggs thoroughly to maintain a soft and creamy texture. If unpasteurized eggs are used, there will be a higher risk of Salmonella contamination, said CFS.

There were 75 outbreaks caused by norovirus, all associated with consuming bivalves. Most of them happened in winter. The absence of valid health certificates was one issue found in several incidents.

CFS suspended the import of raw oysters implicated in the case. The agency has also been conducting operations to ensure that the storage and handling of raw oysters at importer and vendor levels are up to standard.

Incidents this year
CFS has also investigated several incidents so far this year. In March, five people fell sick after eating raw oysters and scallops at a restaurant in Wan Chai. Food was suspected to be contaminated with norovirus and/or Vibrio parahaemolyticus.

In February, 11 people became ill after having a variety of food, including raw oysters and sashimi, at a restaurant in Causeway Bay. Contamination with Vibrio parahaemolyticus or norovirus was suspected.

In January, 27 people who had lunch provided by a food supplier, Chez Lung Catering Co. were reported sick.

Investigations by the Centre for Health Protection (CHP) revealed food poisoning might have been caused by Clostridium perfringens infection, and the food concerned was pork chops with onion sauce. Preliminary findings by CFS revealed the incriminated item was inadequately cooked, with prolonged storage under improper temperature.

Nine people also fell sick in December 2023 after consuming food provided by a caterer. Initial investigations by CHP revealed patients had consumed diced beef and beef ribs in red wine sauce. Clostridium perfringens might have caused the incident.