Emergency Preparedness

Kern Medical Bioterrorism Response Guide Section 2-C-2 – Viral Hemorrhagic Fever

explain the bleeding diathesis. Proteinuria and hematuria are both common in VHF and their absence rules out Argentine and Bolivian HF and hantaviral infections. Hematocrit is generally normal or increased due to dehydration. Liver enzymes (AST) are generally elevated. Differential Diagnoses The major differential diagnosis is malaria. Other diagnoses include typhoid fever, rickettsial and leptospiral diseases, non-typhoidal salmonellosis, shigellosis, relapsing fever, fulminant hepatitis and meningococcemia. Conditions leading to DIC such as acute leukemia, lupus erythematosus, idiopathic or thrombic thrombocytopenia purpura and hemolytic uremic syndrome may lead to the misdiagnosis of VHF. Definitive diagnosis is made by specific virologic testing performed at a biosafety level IV laboratory. Medical Management Patients with VHF syndrome require intensive supportive care. Transporting patients, especially by air, should be avoided because of the effects of changes in ambient pressure on lung water balance. Restlessness, confusion, myalgia, and hyperesthesia occur frequently and should be managed by reassurance and other supportive measures, including the judicious use of sedative, pain-relieving, and amnestic medications. Aspirin and other antiplatelet or anticlotting -factor drugs should be avoided. Secondary infections are common and should treated aggressively. Intravenous lines, catheters, and other invasive devices should be avoided unless clearly indicated for the appropriate management of the patient. Treatment of Bleeding The management of bleeding is controversial. Uncontrolled clinical observations support vigorous administration of fresh frozen plasma, clotting factor concentrates, and platelets, as well as the early use of heparin for prophylaxis of disseminated intravascular coagulation (DIC). In the absence of definitive evidence, mild bleeding manifestations should not be treated. Severe hemorrhage indicates that appropriate replacement therapy is required. When definitive laboratory evidence of DIC becomes available, heparin therapy should be initiated if appropriate laboratory support is available. Treatment of Hypotension and Shock Management of hypotension and shock is difficult. Patients often are modestly dehydrated due to heat, fever, anorexia, vomiting and diarrhea, in any combination. There are losses of intravascular volume through hemorrhage and increased vascular permeability. These patients often respond poorly to fluid infusions and develop pulmonary edema. Colloid or crystalloid solutions should be given cautiously. Although

1