From the Guidelines
Suspect hantavirus infection in patients presenting with fever, muscle aches, headache, and gastrointestinal symptoms who have potential rodent exposure in endemic areas, as the disease can rapidly progress to Hantavirus Pulmonary Syndrome (HPS) with a mortality rate of approximately 38%. The diagnosis should be strongly considered when these initial symptoms progress to respiratory distress, hypoxemia, and bilateral pulmonary infiltrates, particularly if accompanied by thrombocytopenia, leukocytosis, and elevated hematocrit 1. Recent activities that increase risk include:
- Cleaning rodent-infested areas
- Camping
- Working in rural settings where exposure to rodent excreta is likely
- Handling or being exposed to wild rodents, such as mammalogists, pest-control workers, some farm and domestic workers, and building and fire inspectors 1 The incubation period typically ranges from 1-5 weeks after exposure. Early recognition is crucial as the disease can rapidly progress to HPS with respiratory failure and cardiogenic shock. Laboratory confirmation requires specific serologic testing for hantavirus IgM antibodies or PCR detection of viral RNA, but treatment should not be delayed while awaiting results 1. A detailed exposure history is essential for timely diagnosis and supportive care, as the diagnosis is often challenging because early symptoms mimic influenza or other viral illnesses.
From the Research
Hantavirus Diagnosis
When to suspect hantavirus infection is crucial for early diagnosis and treatment. The following points highlight the key factors to consider:
- Clinical and epidemiological information, such as exposure to infected rodents in endemic areas, is essential for diagnosing hantavirus infections in humans 2.
- The main clinical syndromes associated with hantaviruses are haemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS), which have distinct clinical entities but share several features and overlapping symptoms 3.
- Hantavirus pulmonary syndrome (HPS) is a severe disease characterized by a rapid onset of pulmonary edema followed by respiratory failure and cardiogenic shock, with a case fatality rate of approximately 40% 4.
- Early clinical suspicion, access to rapid diagnostic testing, and prompt transfer to a facility with critical care units are critical for improving clinical outcomes in HCPS patients 3.
Diagnostic Tools
Various diagnostic tools are available for detecting hantavirus infection, including:
- Polymerase chain reaction (PCR) 5, 2
- Focus reduction neutralization test (FRNT) 5
- Enzyme-linked immunosorbent assay (ELISA) 5
- Immunoblot assay (IBA) 5
- Immunofluorescence assay (IFA) 5
- Serology, PCR, immunochemistry, and virus culture 2
Epidemiological Considerations
Hantavirus infections are part of the broad group of viral haemorrhagic fevers, with a global distribution influenced by factors such as climate, environment, social development, ecology of rodent hosts, and human behavior in endemic regions 3.