Understanding Hantavirus Risks and the Andes Virus Threat

Finland has officially classified the Andes virus as a communicable disease of public danger. This regulatory step follows increasing international attention on the virus’s unique ability to transmit between humans, distinguishing it from other hantaviruses that typically only spread from animals to people.

The Andes virus is a specific strain of hantavirus responsible for causing Hantavirus Pulmonary Syndrome (HPS). HPS is a severe respiratory disease that affects the lungs and can be potentially deadly if not treated promptly.

While most hantaviruses are zoonotic, meaning they are transmitted from rodents to humans, the Andes virus is notable for its capacity for human-to-human transmission. According to the Centers for Disease Control and Prevention (CDC), the Andes virus is the only type of hantavirus known to spread in this manner.

Andes virus is the only type of hantavirus that is known to spread person-to-person.

Centers for Disease Control and Prevention

Public health officials emphasize that person-to-person spread is usually limited to individuals who have close contact with a sick person. This includes direct physical contact, prolonged time spent in enclosed or close spaces, and exposure to the body fluids of an infected individual.

In addition to human-to-human transmission, the virus can spread through contact with infected rodents or by touching objects contaminated with the virus.

Identifying Symptoms and Progression

The onset of Hantavirus Pulmonary Syndrome due to the Andes virus typically occurs between 4 and 42 days after exposure. Because early symptoms often mimic the flu, initial diagnosis can be challenging.

Early indicators of infection include:

• Fever
• Fatigue
• Muscle aches, particularly in the hips, thighs, back, and shoulders

As the disease progresses, approximately half of all patients experience additional symptoms, including dizziness, headaches, and chills. Some patients also report abdominal issues such as nausea, vomiting, diarrhea, and abdominal pain.

Medical guidance indicates that individuals are typically only infectious to others while they are exhibiting these symptoms.

Global Risk Assessment

Despite the severity of the disease and the ability of the Andes virus to spread between people, health authorities maintain that the broader risk remains low. In guidance updated on May 9, 2026, the CDC stated that the overall risk to the American public and travelers remains extremely low.

The CDC has advised that routine travel can continue as normal, as the rodents that carry the Andes virus have not been found within the United States.

The classification of the virus as a communicable disease of public danger in Finland reflects a precautionary approach to surveillance and containment, ensuring that health systems can respond effectively to any potential cases.

Health professionals advise anyone who believes they have had contact with a person infected with the Andes virus and is experiencing flu-like symptoms to contact a medical professional immediately.