Facts and figures.
- Hantaviruses are a group of viruses transmitted by rodents that can cause severe disease in humans.
- People are usually infected through contact with infected rodents or their urine, droppings, or saliva.
- Hantavirus infections can lead to serious and sometimes fatal illnesses.
In the Americas, hantaviruses can cause Hantavirus Cardiopulmonary Syndrome (HCPS), a severe respiratory disease with fatality rates reaching up to 50%. - The Andes virus, found in South America, is the only hantavirus known to have limited person-to-person transmission among close contacts.
- In Europe and Asia, hantaviruses mainly cause Hemorrhagic Fever with Renal Syndrome (HFRS).
Overview.
Hantaviruses are zoonotic viruses naturally carried by rodents and occasionally transmitted to humans. Infection can lead to severe illness and, in some cases, death. The type of disease depends on the virus strain and geographic region.
In the Americas, hantavirus infection may cause Hantavirus Cardiopulmonary Syndrome (HCPS), a rapidly progressing illness affecting the lungs and heart.
In Europe and Asia, hantaviruses are associated with Hemorrhagic Fever with Renal Syndrome (HFRS), which primarily affects the kidneys and blood vessels.
Although there is currently no specific cure for hantavirus diseases, early supportive medical care significantly improves survival rates by closely monitoring and treating respiratory, cardiac, and renal complications.
Prevention mainly depends on reducing human contact with infected rodents.
Viral Family and Classification.
Hantaviruses belong to the Hantaviridae family within the Bunyavirales order.
Each hantavirus is usually associated with a specific rodent species that carries the virus chronically without becoming visibly ill.
While many hantavirus species have been identified worldwide, only a limited number are known to cause disease in humans.
- Hantaviruses found in North, Central, and South America are known to cause HCPS.
- The Andes virus is notable for its documented limited person-to-person transmission, mainly reported in Argentina and Chile.
- Hantaviruses circulating in Europe and Asia cause HFRS, with no confirmed person-to-person transmission documented in those regions
Global Disease Burden.
Hantavirus infections are relatively rare worldwide but can have high fatality rates.
Fatality rates range from:
- Less than 1% to 15% in Asia and Europe
- Up to 50% in the Americas.
Globally, an estimated 10,000 to more than 100,000 infections occur each year.
Eastern Asia — particularly China and South Korea — reports thousands of HFRS cases annually, although incidence has declined over recent decades.
In Europe, several thousand cases are reported every year, mainly in northern and central regions where the Puumala virus circulates.
In the Americas, HCPS is much less common, with only a few hundred cases annually across the continent. However, despite its lower incidence, its high fatality rate makes it a major public health concern.
Transmission.
Humans become infected through contact with contaminated rodent urine, feces, or saliva.
Infection may also occur through rodent bites, although this is less common.
Higher-risk activities include:
- Cleaning enclosed or poorly ventilated areas
- Agricultural work
- Forestry activities
- Sleeping in rodent-infested buildings
To date, limited person-to-person transmission has only been documented with the Andes virus in South America, primarily among close household contacts or intimate partners.
Symptoms and Clinical Presentation.
Symptoms generally appear between one and eight weeks after exposure and may include:
- Fever
- Headache
- Muscle aches
- Abdominal pain
- Nausea
- Vomiting
In HCPS cases, the disease may rapidly progress to:
- Cough
- Severe breathing difficulty
- Fluid accumulation in the lungs
Shock
In HFRS cases, advanced stages may include:
- Low blood pressure
- Hemorrhagic complications
- Kidney failure
Diagnosis.
Early diagnosis can be difficult because initial symptoms resemble other illnesses such as:
- Influenza
- COVID-19
- Viral pneumonia
- Leptospirosis
- Dengue
- Sepsis
- A detailed medical history is essential,
- especially regarding:
- Rodent exposure
- Occupational and environmental risks
- Travel history
- Contact with confirmed cases
Laboratory confirmation includes:
- Serological testing for hantavirus-specific IgM
- antibodies
- Rising IgG antibody levels
- RT-PCR molecular testing during the acute phase
Because patient samples represent a biological hazard, testing must be performed under strict biosafety conditions.
Treatment.
There is currently:
- No approved antiviral treatment
- No approved vaccine for hantavirus infection
Treatment is supportive and focuses on:
- Intensive monitoring
- Respiratory support
- Cardiac care
- Kidney function management
Early access to intensive care significantly improves survival, especially in HCPS patients.
Prevention and Control
Preventing hantavirus infection depends primarily on minimizing contact with rodents.
Recommended measures include:
- Keeping homes and workplaces clean.
- Sealing openings where rodents may enter
- Storing food securely.
- Using safe cleaning practices in contaminated areas.
- Avoiding dry sweeping or vacuuming rodent droppings.
- Wetting contaminated areas before cleaning
- Practicing proper hand hygiene.
Early identification and isolation of cases, along with contact tracing and infection-control measures, are essential during outbreaks.
Infection Prevention in Healthcare Settings
Current evidence suggests there is a very low risk of hantavirus transmission in healthcare settings when appropriate infection prevention measures are followed.
- Standard precautions include:
- Hand hygiene
- Environmental cleaning
- Safe handling of blood and bodily fluids
When aerosol-generating procedures are performed, airborne precautions should also be implemented.
Early detection, immediate isolation, and strict adherence to infection-control protocols remain critical to protecting healthcare workers.
WHO Response
The World Health Organization works with countries and partners to strengthen:
- Disease surveillance
- Laboratory capacity
- Risk communication
- Community engagement
- Early detection
- Patient care
- Outbreak response
The WHO also promotes integrated One Health approaches that recognize the connection between human health, animal reservoirs, and the environment.
Reference:
1) Jonsson, C. B., Figueiredo, L. T. M., Vapalahti, O. (2010). A global perspective on hantavirus ecology, epidemiology, and disease. Clinical Microbiology Reviews, 23(2), 412 441.
2) Li, et al. 2024. Seroprevalence of hantavirus infection in non-epidemic settings over four decades: a systematic review and meta-analysis. BMC Public Health.
3) Tian, H., Stenseth, N.C., 2019. The ecological dynamics of hantavirus diseases. PLoS Neglected Tropical Diseases.
Source: ORGANIZACIÓN MUNDIAL DE LA SALUD
