infectious diseases
Hantavirus Infection
Hantavirus Pulmonary Syndrome
Hantavirus pulmonary syndrome (HPS) occurs in the United States, primarily in the southwestern states, Canada, primarily in western provinces, and in South America and Panama. It begins as a flu-like illness and, within days, causes noncardiogenic pulmonary edema. Diagnosis is with serologic tests and reverse transcriptase–polymerase chain reaction (RT-PCR). The more severe forms have a case fatality rate of up to 50%. Treatment is supportive. Most casesof HPS are caused by The Sin Nombre, Andes, and Choclo hantaviruses Others are caused by The Black Creek Canal virus, Muleshoe virus, and Bayou virus in the southeastern United States and Mexico The New York virus (a variant of Sin Nombre virus) on the East Coast of the United States The Convict Creek virus and Isla Vista virus on the West Coast of North America The Laguna Negra (and its Rio Mamore variant), Andes-like virus Hu39694, Lechiguanas, Oran, Central Plata, Buenos Aires, Rio Mearim, Juquitiba, Juquitiba-like, Ape Aime Itapua, Araucaria, Jabora, Neembucu, Anajatuba, Castelo dos Sonhos, Maripo, and Bermejo hantaviruses in South America Infection is transmitted to humans via inhalation of excreta of sigmodontine rodents (especially the deer mouse for Sin Nombre virus). Most cases occur west of the Mississippi River in spring or summer, typically after heavy rains that elicit vegetation growth that serves as food that promotes rodent population growth. Hantavirus pulmonary syndrome begins as a nonspecific flu-like illness, with acute fever, myalgia, headache, and gastrointestinal symptoms. Two to 15 days later (median 4 days), patients rapidly develop noncardiogenic pulmonary edema and hypotension. Several patients have had a combination of HFRS and HPS. Mild cases of HPS can occur. Serologic testing or polymerase chain reaction (PCR) Hantavirus pulmonary syndrome is suspected in patients with possible exposure if they have unexplained clinical or radiographic pulmonary edema. Chest x-ray may show increased vascular markings, Kerley B lines, bilateral infiltrates, or pleural effusions. If HPS is suspected, echocardiography should be done to exclude cardiogenic pulmonary edema. Complete blood count, liver tests, and urinalysis are also usually done. HPS causes mild neutrophilic leukocytosis, hemoconcentration, and thrombocytopenia. Modest elevation of lactic dehydrogenase, aspartate aminotransferase, and alanine aminotransferase, with decreased serumalbumin, is typical. Urinalysis shows minimal abnormalities. Diagnosis of HPS is with serologic testing or reverse transcriptase–PCR. Supportive care Treatment of hantavirus pulmonary syndrome is supportive. Mechanical ventilation, meticulous volume control, and vasopressors may be required. For severe cardiopulmonary insufficiency, extracorporal mechanical oxygenation may be lifesaving (see alsoCenters for Disease Control and Prevention: Hantavirus Virus: Treatment) . has not been shown to be effective for treatment of HPS despite its effectiveness in Hemorrhagic Fever With Renal Syndrome . 