There were over 10,000 reported cases of hepatitis A caused by consumption of raw pickled shellfish in South Korea during summer of 2020. Hepatitis A is an infectious disease of the liver caused by hepatitis A virus (HAV) whose transmission mode is different from hepatitis B and hepatitis C. The HAV is mainly transmitted through food and water contaminated by the faeces of an infected person, which means it is closely related to poor food hygiene, unsafe water supply and poor personal hygiene habits.

Macao residents dine out frequently and there has been a rising trend in the number of outbound tourists. If food premises carry out the food production in poor hygiene from cultivation to harvest, processing and handling, consumers are at high risk of contracting hepatitis A through consumption of the food and water contaminated with HAV. In this regard, we can practise the “Five Keys to Food Safety (ABCDE)” in our everyday life to effectively prevent HAV infection and reduce the risk of foodborne diseases.

1)      Avoid Cross-contamination

The HAV can be transmitted directly or indirectly through mediums like food, hands and objects. Hence, separate handling and storing of raw and cooked foods from purchase to serving is the best way to prevent HAV infection.

• Food products must be properly enclosed before placing them in a refrigerator or freezer, e.g. use a covered food container or wrap it with food wrapping film. Always follow the principle of “Keep Raw Food Below Cooked Food” to prevent juices of raw food from dripping onto the interior of the compartment or ready-to-eat food to avoid cross-contamination;
• Raw food and cooked food must be handled separately, e.g. use two sets of cutting boards and cutleries, with one for raw food and one for cooked food. 

2)      Buy Right

The HAV is commonly found in unclean water sources, raw or undercooked shellfish, vegetables and fruits. Be cautious about food sources and make sure to choose foodstuffs that are fresh and look normal.

• Do not buy vegetables, fruits and aquatic products of unknown origins because their hygiene condition and safety are not guaranteed;
• Take precautions with food and water when travelling abroad, e.g. drink boiled water and avoid beverages with ice cubes as well as undercooked food such as salads, sashimi, raw oysters and raw scallions. 

3)      Clean and Cook Completely

The HAV in food is killed by heating at 85ºC or higher within 2 minutes and its spread is associated with poor hygiene practices. In this connection, cooking food thoroughly and boiling drinking water can effectively prevent pathogens infection. It is also important to strictly observe personal, food and environmental hygiene to ensure food safety.

• Maintain environmental hygiene at all times, especially the cleanliness of kitchens, toilets and cooking utensils;
• Wash hands correctly with liquid soap and water after using the toilet and before food preparation to prevent cross-contamination. Stop handling food in the case of gastrointestinal upset, food handlers should seek medical advice immediately;
• When handling shellfish, scrub the shells, clean and wash them thoroughly with running water and remove the viscera;
• When the shellfish is cooking at high temperatures, the shells open and continue cooking for another 3 to 5 minutes to make sure the meat is fully cooked;
• Pathogens cannot be killed by spicy and acidic condiments such as Japanese mustard (i.e., wasabi), chili sauce, lemon juice, vinegar and liquor. Recent research reveals that the HAV is found in pickled and smoked raw aquatic products; therefore, it is best to avoid eating high-risk food such as soy sauce-marinated raw crabs (i.e., Ganjang Gejang) and pickled clams;
• High-risk groups, such as infants, children, pregnant women and the elderly, should eat thoroughly cooked food and drink boiled water. 

4)      Danger Temperature Zone

The HAV only becomes active and reproduces in its natural hosts, i.e. humans and several species of non-human primates. Even though the virus may persist on the above-mentioned carriers like the foods and water, it remains inactive within the Danger Temperature Zone (between 5°C and 60°C). On the contrary, bacteria multiply and grow rapidly in that temperature range that poses a threat to food safety. Adequate controls of food temperature and food storage time can reduce the incidence of food poisoning.

• Perishable food and the raw ready-to-eat cold food, such as meat, aquatic products, eggs, dairy products and salads, must be stored below 5⁰C;
• Hot food must be kept above 60⁰C;
• Do not handle or display food at room temperature for more than two hours. 

5)      Efforts to Maintain Macao Food Safety

Food safety relies on the joint efforts of the government, food trade and residents. To prevent the spread of foodborne diseases in the community, let us practise the “Five Keys to Food Safety (ABCDE)” in everyday life and raise our awareness of food safety and personal protection.

037/DIR/DSA/2019