Detection of hepatitis A virus in the feces of patients with naturally acquired infections.

A prospective study was carried out on 200 patients admitted to Fairfield Hospital, Melbourne, Australia, with acute hepatitis A to determine the frequency with which virus could be detected in their feces. Evidence of infection with hepatitis A virus (HAV) was obtained by detecting IgM specific for HAV in a single serum sample or by demonstrating a rising titer of antibody in paired sera by solid-phase radioimmunoassay. HAV was detected in the feces of 59 of the 200 patients by solid-phase radioimmunoassay and immune electron microscopy. When patients were admitted within one week of the onset of dark urine, 45% were found to be shedding HAV, whereas only 11% of specimens obtained from patients admitted during the second week contained virus. HAV was not detected in fecal specimens collected more than 14 days after the onset of dark urine. These findings suggest that patients admitted to hospital with hepatitis A may still be infectious and that appropriate precautions against fecal contamination should be maintained.