Persistence of infectious hepadnavirus in the offspring of woodchuck mothers recovered from viral hepatitis

Mother-to-child transmission is an important route for hepatitis B virus (H BV) dissemination. It has been established that HBV traces persist for year s after complete clinical recovery from hepatitis B. Similarly, resolution of hepatitis caused by HBV-related woodchuck hepatitis virus (WHV) is follo wed by occult lifelong carriage of pathogenic virus. In this study, we docu mented that WHV persisting after termination of acute hepatitis is transmit table to newborns as an asymptomatic long-term infection. All 11 offspring from 4 darns studied carried transcriptionally active WHV genomes for 3.5 y ears after birth without immunovirological markers of infection. WHV genome s and mRNA were detected both in the liver and lymphoid tissue in the major ity of offspring; WHV covalently closed circular DNA was detected in some s amples. In 4 offspring, however, the virus was restricted to the lymphatic system. In the circulation, WHV DNA-reactive particles were DNase resistant and of comparable size and density to complete virions. Importantly, the v irus in offspring with or without hepatic WHV DNA expression was infectious to WHV-naive woodchucks. Finally, offspring challenged with WHV were not p rotected against reinfection. These findings show that mothers with occult hepadnaviral carriage transmit pathogenic virus to their offspring, inducin g a persistent infection invariably within the lymphatic system but not alw ays in the liver.