What Is Hantavirus?

Recent reports of hantavirus infections aboard an Antarctic expedition cruise ship in the Atlantic Ocean have drawn international attention. According to health authorities, eight cases have been identified so far, including three fatalities. The World Health Organization currently considers the overall global risk to be low and has not recommended any travel or trade restrictions.

What is hantavirus?

Hantavirus belongs to the Bunyaviridae family and is mainly transmitted by rodents, especially rats.
The virus is commonly found in the urine, feces, or saliva of infected rodents. In China, the striped field mouse and the Norway rat are the primary host animals and sources of infection.

What are the symptoms after infection?

Hantavirus infection in humans mainly presents as two clinical syndromes:

• Hemorrhagic Fever with Renal Syndrome (HFRS)  
• Hantavirus Pulmonary Syndrome (HPS)  

HFRS is more common in Asia and Europe and is characterized by fever, bleeding, and kidney damage. Typical symptoms include the “three pains”:

• headache  
• lower back pain  
• orbital pain  

and the “three rednesses”:

• facial flushing  
• neck redness  
• chest redness  

The disease usually progresses through five stages:

1. febrile stage  
2. hypotensive stage  
3. oliguric stage  
4. polyuric stage  
5. recovery stage  

In China, HFRS is classified as a Category B infectious disease.

The cruise ship outbreak involved Hantavirus Pulmonary Syndrome (HPS), caused by the Andes hantavirus strain. This form is mainly found in the Americas. Early symptoms are nonspecific and resemble influenza, including high fever and muscle pain. The disease can progress rapidly, leading to pulmonary edema, shock, respiratory failure, and other severe complications.

How is hantavirus transmitted?

Hantavirus is mainly spread through contact with the urine, feces, or saliva of infected rodents. Human-to-human transmission is extremely rare.

The main routes of transmission include:

• Respiratory transmission: inhalation of dust or aerosols contaminated with infected rodent urine, feces, or saliva.  

• Direct contact transmission: contact with rodent excreta, secretions, or bites, allowing the virus to enter through broken skin or mucous membranes.  

• Digestive tract transmission: consumption of food or water contaminated with the virus.  

• Rare human-to-human transmission: the Andes virus is currently the only known hantavirus strain capable of person-to-person transmission. Transmission may occur during close and prolonged contact, such as cohabitation, caregiving, or sharing a cabin with an infected person.  

How can hantavirus infection be prevented?

Experts emphasize that the key to preventing hantavirus infection is controlling rodent populations and reducing human exposure to rodents. Recommended measures include:

• maintaining clean and sanitary environments  

• implementing rodent prevention and extermination measures  

• avoiding contact with rodents and their excreta  

• wearing masks and gloves when cleaning potentially contaminated areas, and spraying water first to reduce dust  

• practicing good food hygiene and preventing rodent contamination of food and water sources