Hong Kong health officials report investigating a case of human infection of rat Hepatitis E virus (HEV).
The case is a a 91-year-old man with underlying illnesses. He was sent to the Accident and Emergency Department of Queen Elizabeth Hospital on September 16 due to a fever and weakness in four limbs. Routine blood tests revealed that he had abnormal liver function. His blood sample tested positive for rat HEV upon laboratory testing by the Public Health Laboratory Services Branch under the CHP. The patient's symptoms were relatively mild, and he remains in stable condition. After receiving treatment, he recovered and was discharged on September 21.
This is the third case of human infection of rat HEV recorded so far this year.
Human cases of rat hepatitis E virus infection affect mostly immunocompromised persons. Most cases are asymptomatic, while symptomatic patients reported mild symptoms, such as fatigue, abdominal pain and loss in appetite. It is less likely for patients with rat HEV infection to develop jaundice compared to HEV infected patients.
Rat hepatitis E infections in Hong Kong
The possible routes of transmission of rat HEV to humans include ingestion of food or water contaminated by rodents or their excreta, exposure to environments or objects contaminated by rodents or their excreta and direct contact with rodents or their excreta. The HEV that usually causes human infection is mainly transmitted through the faecal-oral route.
To prevent infection, the members of the public should maintain good personal, food and environmental hygiene. For example, they should wash their hands thoroughly before eating, store food properly or in the refrigerator, avoid leaving food at room temperature for a long time, and use 1:99 diluted household bleach for general household cleaning and disinfection as household detergents may not kill HEV.
The Five Keys to Food Safety should be adopted when handling food, i.e. Choose (choose safe raw materials), Clean (keep hands and utensils clean), Separate (separate raw and cooked food), Cook (cook thoroughly) and Safe Temperature (keep food at a safe temperature), to prevent food-borne diseases.
In general, rodents (such as rats) can transmit multiple diseases to humans, both directly and indirectly. The public is advised to take the following measures:
Eliminate sources of food and nesting places for rodents in the living environments. Store food in covered containers and handle pet food properly to prevent it from becoming food for rodents;
Store all refuse and food remnants in dustbins with well-fitted covers. Dustbins must be emptied at least once a day;
Keep premises, especially refuse rooms and stairways, clean. Avoid accumulation of articles;
Inspect all flower beds and pavements regularly for signs of rodent infestation; and
Avoid the high-risk activities below to reduce rodent contact:
- Avoid contact with rodents and areas contaminated by rodent excreta;
- Avoid handling rodents with bare hands;
- Wash hands with liquid soap and water immediately after handling animals, and disinfect contaminated areas; and
- If a wound appears, clean the broken skin immediately and cover it properly with waterproof adhesive dressings.