Hepatitis A-virus particles in stools of patients from a natural hepatitis outbreak in Germany.

During a hepatitis outbreak in Southern Germany 27 nm particles were visualized by immune electron microscopy in stools of two patients. These particles were sereologically identical or similar to hepatitis A-virus particles identified in the USA. The buoyant density of these particles was 1.34 g/cm3 as shown by cesium chloride density centrifugation. The particles were first observed in small numbers in a stool obtained 11 days, and in large numbers in stools obtained 6 and 7 days before the onset of jaundice. Few particles were seen on the day of the onset of jaundice and none thereafter. In both patients a sereoconversion to hepatitis A-virus as judged by immune electron microscopy could be demonstrated.