Hantavirus

Background

• Enveloped, single-stranded RNA virus within the order Bunyavirales
• Acquired by inhalation of contaminated rodent urine or feces, and possibly by bites
• Essentially worldwide, though New World viruses tend to cause hantavirus pulmonary syndrome and Old World viruses tend to cause hemorrhagic fever with renal syndrome

Clinical Manifestations

• Incubation period of 14 days (range 5 to 42 days)

Hemorrhagic Fever With Renal Syndrome (HFRS)

• Caused by Old World hantaviruses, such as Hantaan, Dobrava, Seoul, Puumala, and other Old World hantaviruses
• Fever, thrombocytopenia, and AKI caused by acute interstitial nephritis
• Also headache, abdominal pain, low back pain, dizziness, and blurred vision
• Can have conjunctival injection and petechiae on upper trunk and soft palate
• Febrile phase lasts 4 to 7 days of acute, severe illness, followed by hypotensive, oliguric, and polyuric phases
• Leukocytosis and thrombocytopenia seen on CBC
• Mortality up to 5%

Hantavirus Pulmonary Syndrome (HPS)

• Caused by New World hantaviruses such as Sin Nombre, Bayou, and Black Creek Canal
• Prodrome of fever followed 4 to 5 days later by shock and pulmonary edema
  • Prodrome may include myalgias, abdominal pain, and gastrointestinal symptoms
  • Respiratory failure can develop quickly
• Elevated hematocrit (from third-spacing), leukocytosis, atypical lymphocytes, mild thrombocytopenia, prolonged PTT, and mild elevations in AST and LDH
• Creatinine may be elevated, but not as severe as HFRS

Differential Diagnosis

• HPS: other causes of unexplained pulmonary edema

Diagnosis

• Serology usually positive by presentation (both IgM and IgG)
• PCR or immunohistochemical staining are both possible
• Viral culture is difficult

Management

• Supportive