Welcome to the Hantavirus Outbreak toolbox

• Hantavirus Fact sheet (WHO, 2026)
  
• Hantavirus in the Americas: guidelines for prevention, diagnosis, treatment, and control (PAHO, 1999) (EN, ES)
• Hantavirus (United States Centers for Disease Control and Prevention, USCDC, 2024)
• Hantavirus case definition and reporting (USCDC, 2025)

Suggested Hantavirus pulmonary syndrome surveillance case definition*

Suspected case

• A person who presents with a febrile illness (Fever > 38.5 °C [103 °F] oral) with an acute respiratory distress syndrome requiring supplemental oxygen AND bilateral diffuse infiltrates developed within 72 hours of hospitalization in a previously healthy person 
• Unexplained illness resulting in death plus an autopsy examination demonstrating noncardiogenic pulmonary oedema without an identifiable specific cause of death

Confirmed case

A suspected case laboratory confirmed with:

• The presence of hantavirus-specific IgM antibodies or a 4-fold or greater increase in IgG antibody titres or hantavirus-specific IgG seroconversion.
• A positive reverse transcriptase-polymerase chain reaction (RT-PCR) results for hantavirus RNA.
• Positive immunohistochemical results for hantavirus antigens.

*These definitions are suggested to be used for surveillance purposes in the Americas (Hantavirus in the Americas: guidelines for prevention, diagnosis, treatment, and control (PAHO, 1999)). Different case definitions may be used during outbreaks and in different contexts.