Open Outbreak

Hantavirus infection

Also known as: hantavirus, HPS, HFRS, HCPS, hantavirus pulmonary syndrome, hantavirus cardiopulmonary syndrome, haemorrhagic fever with renal syndrome, hemorrhagic fever with renal syndrome, Orthohantavirus infection

Hantavirus infection is a group of illnesses caused by hantaviruses carried mainly by rodents. In Europe and Asia, infection more often causes haemorrhagic fever with renal syndrome, which can affect the kidneys and sometimes cause bleeding. In the Americas, it more often causes hantavirus pulmonary or cardiopulmonary syndrome, which can rapidly damage the lungs and heart. People usually get infected by breathing in virus-contaminated dust from rodent urine, droppings, or saliva, or by direct contact with these materials. Most hantaviruses are not known to spread easily between people, but Andes virus has caused limited person-to-person spread in some outbreaks. Severity varies by virus. A 2019 review reported case fatality of about 5% to 15% for HFRS and up to 40% for HCPS. There is no broadly proven antiviral treatment. Care is mainly supportive, often in intensive care for severe lung disease. Inactivated vaccines exist only in some countries for certain HFRS-causing viruses.

Key facts

TransmissionUsually through inhalation of aerosolized rodent urine, droppings, or saliva, or direct contact with infected rodent excreta; limited person-to-person transmission has been reported for Andes virus.
Incubationunknown
Case fatalityHFRS: about 5% to 15%; HCPS/HPS: up to 40% in a 2019 review, and WHO noted 40% to 50% can occur in severe outbreaks.
Reproduction numberunknown; limited human-to-human transmission has been documented for Andes virus, but an established overall R0 was not found in the sources reviewed.
VaccineNo widely available global vaccine. Whole-virus inactivated vaccines against Hantaan virus or Seoul virus are used in China and the Republic of Korea for some HFRS risks.
TreatmentNo effective specific treatment established in the reviewed sources; management is mainly supportive care, with early intensive care for severe cardiopulmonary disease.
ReservoirMainly rodents.
Endemic regionsRodent-associated hantaviruses occur across Asia, Europe, and the Americas; Andes virus remains endemic in South America according to WHO.

Transmission

Hantaviruses are mainly rodent-borne infections. People usually become infected after breathing in tiny particles contaminated by rodent urine, droppings, or saliva. Infection can also follow direct contact with contaminated materials. The main risk settings are places where infected rodents live or enter, such as farms, fields, forests, sheds, cabins, and other buildings with poor rodent control. A major review describes hantaviruses as viruses maintained in rodents, with human disease caused by spillover from these animal hosts. WHO outbreak notices use similar language and say most human infections are acquired through contact with infected rodent excreta. Human-to-human spread is not the norm. WHO and recent literature both note that Andes virus is an exception: limited person-to-person transmission has been documented, usually after close and prolonged exposure rather than casual contact.

Symptoms and severity

Hantavirus infection is not one single illness. In Europe and Asia it often appears as HFRS, which can cause fever, headache, abdominal pain, nausea, bleeding problems, and kidney injury or failure. In the Americas it more often appears as HPS or HCPS, which may start with fever, tiredness, muscle pain, and stomach symptoms, then rapidly progress to cough, pneumonia, acute respiratory distress, shock, and death. Severity can change quickly, especially with HPS. A 2019 review reported case fatality of about 5% to 15% for HFRS and up to 40% for HCPS. WHO’s 2026 Andes-virus outbreak reports also warned that disease can be severe, and in that cruise-ship cluster reported three deaths among early cases. Because early symptoms can look like influenza or stomach illness, the dangerous lung phase may not be obvious at first.

Treatment and vaccines

The sources reviewed do not describe a widely proven cure for hantavirus infection. A 2019 review states that there is currently no effective treatment available for either HFRS or HCPS. In practice, treatment is supportive. That means careful monitoring, oxygen, fluids managed by experienced clinicians, and intensive care when breathing or circulation fail. This is especially important for HCPS, which can worsen fast. Vaccine availability is limited. The same review says only whole-virus inactivated vaccines against Hantaan virus or Seoul virus are in use, and these are used in China and the Republic of Korea. That is not the same as a widely available vaccine for all hantaviruses worldwide, and there is no broadly available vaccine for the Andes-virus outbreaks discussed by WHO. For the general public, reducing contact with rodents and their droppings remains the main prevention measure in the sources reviewed.

Where it occurs

Hantavirus infection occurs in many parts of the world, but the type of illness differs by region because different hantaviruses circulate in different rodent hosts. The literature describes HFRS as the main pattern in Europe and Asia, while HPS or HCPS is the main pattern in the Americas. WHO’s 2026 updates say Andes virus remains endemic in South America. WHO outbreak records in this session also show past events in Bosnia and Herzegovina, Panama, Argentina, the United States, and multi-country events in the Americas, which matches that broad geographic pattern. Risk is linked less to country borders than to local ecology: where infected rodent species live, where their droppings contaminate air or surfaces, and where people work, travel, camp, or clean in those settings. Rural and outdoor environments are common exposure settings, but buildings can also be risky if rodents are present.

Recent history

This site’s archive lists 7 hantavirus-related WHO or major historical events since 1996. The older records in this session include HFRS in Bosnia and Herzegovina in 1996, HPS in Panama in 2000, a multi-country Americas item in 1997, and the Yosemite National Park outbreak in the United States in 2012. WHO also posted notices on Panama and Argentina in 2019. The most notable recent event in the WHO archive here is the 2026 Andes-virus outbreak linked to the cruise ship M/V Hondius. WHO published a series of updates from 2026-05-04 to 2026-07-02. By 2026-07-02, WHO reported 13 cases linked to that event, including three deaths, and judged that no further related transmission was expected. WHO’s overall risk assessment for the global population stayed low, while risk for exposed passengers and crew was managed as a more immediate concern during follow-up.

What to watch

The main warning signs would be changes in how hantavirus spreads, where it appears, and how well health systems can control severe cases. The biggest signal would be more sustained human-to-human transmission, especially outside the limited Andes-virus pattern described by WHO and recent reviews. Another concern would be spread into new regions or unusual settings, including large travel-linked clusters, because that can delay recognition and contact tracing. Public-health teams also watch for changes in severity, such as higher case fatality than usual for a known virus, or more cases progressing rapidly to respiratory failure. Because there is no broadly proven specific treatment in the reviewed sources and vaccine availability is limited to certain inactivated HFRS vaccines in some countries, shortages of intensive-care capacity or vaccine supply for affected regions would matter. Finally, any evidence that rodent exposure is increasing after environmental disruption would also raise concern, because spillover remains the main route into humans.

Updated