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Natural Duck Hepatitis B Virus (DHBV) infection has been studied in Australian ducks. Sera from 430 Pekin Aylesbury cross-bred ducks taken from three separate flocks were examined for duck hepatitis B virus (DHBV) DNA using a DNA dot hybridisation assay. In one flock there was significant infection with DHBV (98/140), but none was detectable in the other two flocks. Episomal DHBV DNA in liver tissue was demonstrated by gel blot hybridisation only in birds with DHBV DNA in serum. Polymerase-labelled DHBV DNA migrated as expected for linear double-stranded DNA 3-1 kilobase (kb) in length. Virus particles with characteristic DHBV morphology were observed in DHBV DNA-positive serum on electron microscopy. No overt morbidity has been noted in naturally infected ducks, but moderately severe hepatitis was found in 3/40 ducks examined histologically. These 3 ducks had DHBV DNA in serum and liver tissue. Mild hepatitis was observed in 27 ducks, but, in these, there was no correlation between the hepatitis and the presence of DHBV in serum or in liver tissue. This is the first report of DHBV in Australia. An animal model may now be established to study aspects of Hepadna virus infection which are pertinent to Hepatitis B virus (HBV) disease in man. [ABSTRACT FROM AUTHOR]

The persistence of Langerhans cells, melanocytes and ABH red cell antigens in human epidermal cell cultures derived from neonatal foreskin explants has been investigated. Langerhans cells were recognised via the detection of ATPase activity and by immunohistochemical staining for T6 and HLA-DR antigens. Melanocytes were detected by the dihydroxyphenylalanine (DOPA) technique; whilst the presence of red cell antigens was confirmed by immunohistochemical tests using monoclonal anti-A, anti-B, and anti-H antibodies. Langerhans cells were not detected in the cultured epidermis, and few melanocytes were found more than 0-2 mm from the periphery of the explants. However, both Langerhans cells and melanocytes were found to persist for up to 4 weeks in the explants themselves. Red cell antigens, consistent with the blood group of the donor infant, were consistently detected on the surface of the differentiating keratinocytes throughout their in vitro lifespan. The significance of these findings is discussed. [ABSTRACT FROM AUTHOR]

The literature concerning hepatitis B in pregnancy is reviewed and problems of management of both the acute and chronic infections are discussed. [ABSTRACT FROM PUBLISHER]

Hepatitis B core antigen (HBcAg) was prepared from human liver tissue and used in an immunoelectro-osmophoresis screening test to detect antibody to HBcAg (anti-HBc) in patients with evidence of liver disease and in blood donors. With the exception of two immunosuppressed HBsAg carriers, anti-HBc was found in all cases of hepatitis B infection even when HBsAg was detectable only by radioimmunoassay. Non-specific reactions were observed in 'non-B' hepatitis but, in spite of this problem, antib-HBc screening was considered a useful addition to routine tests in the clinical hepatitis laboratory. [ABSTRACT FROM PUBLISHER]

Background: Reports from around the world indicate that multiply transfused patients are at increased risk of hepatitis C virus (HCV) infection, with reported rates of between 4% and 44%. Such reports are mostly of haematological and renal patients. As recipients of blood products in the newborn period, premature infants share this risk, but there is little information regarding their risk. Aim: To assess the risk of HCV infection in children who, as premature neonates, received multiple blood products prior to the introduction of screening of donated blood for HCV. Methods: Premature infants born between January 1985 and January 1990 who had attended our high-risk follow-up clinic were selected on the basis of the number of transfusions of blood, platelets or fresh frozen plasma they received in the newborn period. Ethical approval to offer HCV testing to parents was obtained from the Central Sydney Area Health Service Ethics Review Committee. Parents of infants who received three or more transfusions were then contacted by mail with the approved letter explaining the study, and offered HCV testing. Detection of anti-HCV antibodies was undertaken using second, and later third generation enzyme immunoassay kits. Samples which were found to be ‘indeterminate’ were tested using a Wellcozyme HCV western blot assay (Murex Diagnostics Ltd, Datford, UK). Hepatitis C virus–ribonucleic acid (RNA) was detected using an ‘in-house’ polymerase chain reaction (PCR) assay. Alanine transaminase (ALT) was also measured, with values above 55 U/L considered abnormal. Results: Consent was obtained for 45 children (25 males, 20 females). The mean (± SEM) gestational age and weight of the children at birth was 26.7 ± 0.2 weeks and 938 ± 27 g, respectively. The children received 198 transfusions of blood products, an average of 4.4 U per child. All of the infants except for one were negative for anti-HCV antibodies. One infant was ‘indeterminate’ (low positive on third generation test but negative on second generation test), but proved negative subsequently on both western blot and PCR testing. HCV–RNA was not detected in any of the infants on PCR testing. All of the samples had normal ALT values, the mean being 16 U/L (range 8–52). Conclusion: None of the children consenting to this study had evidence of current HCV infection. Because of the sample size, we were not able to estimate the true risk of infection from this study, except that the upper limit for the risk is about 1/200 per transfused blood sample. [ABSTRACT FROM AUTHOR]

A new commercial test for hepatis B surface antigen based on an enzyme-linked immunosorbent-assay system was evaluated and compared with other tests already available. It was of comparable sensitivity to the radioimmunoassay test but required less expensive equipment (in terms of both outlay and upkeep) and did not use radioisotopes; the reagents were more stable. [ABSTRACT FROM PUBLISHER]