This letter is to inform you of the early signs and symptoms of HPS and to let you know what resources are available for diagnosis, treatment and prevention of the disease. Clinical Recognition of the hantavirus prodrome. HPS begins one to six weeks after exposure to infected rodents or their excreta, although not all patients will give a history of rodent exposure. All patients experience a prodromal phase with fever, chills and myalgias, persisting for 1 to 7 days before progression to the cardiopulmonary phase. Pain in the legs and back can be very severe in hantavirus prodrome.
Many patients also experience nausea, vomiting and diarrhea.
Cough and other upper respiratory symptoms are not present at the onset of the prodromal phase but instead begin hours before the onset of the noncardiogenic pulmonary edema and cardiogenic shock. Presumptive laboratory recognition of the hantavirus prodrome. Other nonspecific lab results suggestive of prodromal HPS include elevated LDH, elevated AST, and reduced serum bicarbonate. With the onset of pulmonary edema, the CBC now shows thrombocytopenia, elevated hematocrit, leukocytosis with circulating myelocytes and promyelocytes, and immunoblasts, recognized as large atypical lymphocytes with deep blue cytoplasm. Serum creatinine is usually not elevated unless dehydration due to vomiting and diarrhea is severe.