Hepatitis: Boxall EH

Mathew JL, El Dib R, Mathew PJ, Boxall EH, Brok J. · Department of Pediatrics, Advanced Pediatrics Centre, Postgraduate Institute of Medial Education and Research (PGIMER), Chandigarh, India, 160012. · Cochrane Database Syst Rev. · Pubmed #18677780 No free full text.

Abstract: BACKGROUND: The benefits and harms of hepatitis B vaccination in persons not previously exposed to hepatitis B infection or with unknown exposure status have not been established. OBJECTIVES: To assess the benefits and harms of hepatitis B vaccination in people not previously exposed to hepatitis B infection or with unknown exposure status. SEARCH STRATEGY: Trials were identified from The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, LILACS,Science Citation Index Expanded (last search, March 2007). Additionally, we contacted experts and vaccine manufacturers, and read through reference lists for eligible trials. SELECTION CRITERIA: Randomised clinical trials comparing hepatitis B vaccine versus placebo, no intervention, or another vaccine in persons not previously exposed to hepatitis B (HBsAg negative) or with unknown exposure status. DATA COLLECTION AND ANALYSIS: The primary outcome was hepatitis B infection (detecting HBsAg, HBeAg, HBV DNA, or anti-HBc). Secondary outcomes were lack of sero-protection, antibody titre, clinical complications, adverse events, lack of compliance, and cost-effectiveness. Dichotomous outcomes were reported as relative risk (RR) with 95% confidence interval (CI), using intention-to-treat analysis assuming an unfavourable event for missing data. Sensitivity analyses based on methodological quality (risk of bias), available data analysis, intention-to-treat analysis assuming a favourable event for missing data, best-case scenario, and worst-case scenario were conducted. MAIN RESULTS: Twelve trials were eligible. All had high risk of bias and reporting was inconsistent. Hepatitis B vaccine did not show a clear effect on the risk of developing HBsAg (RR 0.96, 95% CI 0.89 to 1.03, 4 trials, 1230 participants) and anti-HBc (RR 0.81, 95% CI 0.61 to 1.07; 4 trials, 1230 participants, random-effects) when data were analysed using intention-to-treat analysis assuming an unfavourable event for missing data. Analysis based on data of available participants showed reduced risk of developing HBsAg (RR 0.12, 95% CI 0.03 to 0.44, 4 trials, 576 participants) and anti-HBc (RR 0.36, 95% CI 0.17 to 0.76, 4 trials, 576 participants, random-effects). Intention-to-treat analysis assuming favourable outcome for missing data showed similar reduction in risk. Hepatitis B vaccination had an unclear effect on the risk of lacking protective antibody levels (RR 0.57, 95% CI 0.26 to 1.27, 3 trials, 1210 participants, random-effects). Development of adverse events was sparsely reported. AUTHORS' CONCLUSIONS: In people not previously exposed to hepatitis B, vaccination has unclear effect on the risk of developing infection, as compared to no vaccination. The risk of lacking protective antibody levels as well as serious and non-serious adverse events appear comparable among recipients and non-recipients of hepatitis B vaccine.

Price N, Boxall EH. · Health Protection Agency, West Midlands Public Health Laboratory, Heart of England NHS Foundation Trust, Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK. · J Antimicrob Chemother. · Pubmed #17913721 links to  free full text

Abstract: We have reviewed the current strategies regarding the treatment of persistent hepatitis B virus (HBV) in children and compared these with adult strategies. The options for achieving suppression of viral DNA replication versus hepatitis B e antigen to antibody seroconversion have been evaluated. The results of studies in different geographical locations have been confounded by HBV genotypes, as it is now clear that some genotypes respond better to treatment than others. Consideration needs to be given as to whether optimal treatment strategies developed for adults are directly applicable to children. In children, early seroconversion to allow improved long-term outcomes should be considered rather than embarking on the long-term complexities of managing patients on a combination of antiviral drugs to achieve viral suppression.

Lee C, Gong Y, Brok J, Boxall EH, Gluud C. · No affiliation provided · Cochrane Database Syst Rev. · Pubmed #16625613 No free full text.

Abstract: BACKGROUND: Hepatitis B vaccine and hepatitis B immunoglobulin are considered for newborn infants of HBsAg-positive mothers to prevent hepatitis B infection. OBJECTIVES: To assess the beneficial and harmful effects of hepatitis B vaccines and hepatitis B immunoglobulin in newborn infants of HBsAg-positive mothers. SEARCH STRATEGY: Trials were identified through The Cochrane Neonatal Group Controlled Trials Register, The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials in The Cochrane Library, MEDLINE, and EMBASE (until February 2004), authors of trials, and pharmaceutical companies. SELECTION CRITERIA: Randomised clinical trials comparing: plasma-derived vaccine (PDV) or recombinant vaccine (RV) versus no intervention, placebo, or other active vaccines; hepatitis B immunoglobulin versus no intervention, placebo, or other control immunoglobulin; as well as PDV or RV plus hepatitis B immunoglobulin versus no intervention, placebo, or other control vaccines or immunoglobulin. DATA COLLECTION AND ANALYSIS: Outcomes are assessed at maximal follow-up. The primary outcome measure was hepatitis B occurrence, based on a blood specimen positive for HBsAg, HBeAg, or antibody to hepatitis B core antigen (anti-HBc). Binary outcomes are reported as relative risks (RR) with 95% confidence interval (CI). Subgroup analyses were performed with regard to methodological quality of the trial, mother's HBe-Ag status, and time of immunisation after birth. MAIN RESULTS: We identified 29 randomised clinical trials, five of which were considered high quality. Only three trials reported inclusion of hepatitis B e-antigen negative mothers. Compared with placebo/no intervention, vaccine reduced hepatitis B occurrence (RR 0.28, 95% confidence interval (CI) 0.20 to 0.40, 4 trials). No significant differences of hepatitis B occurrence were found comparing recombinant vaccine (RV) versus plasma-derived vaccine (PDV) (RR 1.00, 95% CI 0.71 to 1.42, 4 trials) and high-dose versus low-dose vaccine (PDV: RR 0.97, 95% CI 0.55 to 1.68, 3 trials; RV: RR 0.78, 95% CI 0.31 to 1.94, 1 trial). Compared with placebo/no intervention, hepatitis B immunoglobulin or the combination of vaccine plus hepatitis B immunoglobulin reduced hepatitis B occurrence (hepatitis B immunoglobulin: RR 0.50, 95% CI 0.41 to 0.60, 1 trial; PDV plus hepatitis B immunoglobulin: RR 0.08, 95% CI 0.03 to 0.17, 3 trials). Compared with vaccine, vaccine plus hepatitis B immunoglobulin reduced hepatitis B occurrence (RR 0.54, 95% CI 0.41 to 0.73, 10 trials). Hepatitis B vaccine and hepatitis B immunoglobulin seem safe, but few trials reported on adverse events. AUTHORS' CONCLUSIONS: Vaccine, hepatitis B immunoglobulin, and vaccine plus hepatitis B immunoglobulin prevent hepatitis B occurrence in newborn infants of HBsAg positive mothers.

Lee C, Gong Y, Brok J, Boxall EH, Gluud C. · Cochrane Hepato-Biliary Group, Copenhagen Trial Unit, Copenhagen University Hospital, Denmark. · BMJ. · Pubmed #16443611 links to  free full text

Abstract: OBJECTIVE: To evaluate the effects of hepatitis B vaccine and immunoglobulin in newborn infants of mothers positive for hepatitis B surface antigen. DESIGN: Systematic review and meta-analysis of randomised clinical trials. DATA SOURCES: Electronic databases and hand searches. REVIEW METHODS: Randomised clinical trials were assessed for methodological quality. Meta-analysis was undertaken on three outcomes: the relative risks of hepatitis B occurrence, antibody levels to hepatitis B surface antigen, and adverse events. RESULTS: 29 randomised clinical trials were identified, five of which were considered high quality. Only three trials reported inclusion of mothers negative for hepatitis B e antigen. Compared with placebo or no intervention, vaccination reduced the occurrence of hepatitis B (relative risk 0.28, 95% confidence interval 0.20 to 0.40; four trials). No significant difference in hepatitis B occurrence was found between recombinant vaccine and plasma derived vaccine (1.00, 0.71 to 1.42; four trials) and between high dose versus low dose vaccine (plasma derived vaccine 0.97, 0.55 to 1.68, three trials; recombinant vaccine 0.78, 0.31 to 1.94, one trial). Compared with placebo or no intervention, hepatitis B immunoglobulin or the combination of plasma derived vaccine and hepatitis B immunoglobulin reduced hepatitis B occurrence (immunoglobulin 0.50, 0.41 to 0.60, one trial; vaccine and immunoglobulin 0.08, 0.03 to 0.17, three trials). Compared with vaccine alone, vaccine plus hepatitis B immunoglobulin reduced hepatitis B occurrence (0.54, 0.41 to 0.73; 10 trials). Hepatitis B vaccine and hepatitis B immunoglobulin seem safe, but few trials reported adverse events. CONCLUSION: Hepatitis B vaccine, hepatitis B immunoglobulin, and vaccine plus immunoglobulin prevent hepatitis B occurrence in newborn infants of mothers positive for hepatitis B surface antigen.

Boxall EH, Sira J, Ballard AL, Davies P, Kelly DA. · Liver Unit, Birmingham Children's Hospital NHS Trust, Birmingham, United Kingdom. · J Med Virol. · Pubmed #16721856 No free full text.

Abstract: The long-term outcome of treatment with Interferon Alpha 2B with and without Prednisolone priming in children infected perinatally with hepatitis B was reviewed. The group studied included 48 children (aged 2-16 years), who were HBe antigen and hepatitis B DNA positive between 1991 and 1993. Twenty children were randomized to a therapeutic trial at that time, and received Prednisolone in reducing doses for 6 weeks and Interferon for 16 weeks while 22 children were monitored without treatment for 12 months. Fourteen of the untreated group and 6 additional children later received treatment with Interferon alone (n = 20). Eight children for whom treatment was declined were followed long term. Median follow-up was 7.5 years (range 1.5-10.6). There was no significant effect of Interferon therapy on seroconversion with or without Prednisolone at 12 months post-treatment compared to untreated children. On longer term follow-up, the 5-year HBeAg to anti-HBe seroconversion percentages, estimated from Kaplan-Meier curves, were 54% for Prednisolone plus Interferon, 22% for Interferon alone, and 12% for untreated children. The median time to seroconversion was 3.9 years (range 0.4-8.2) and was shortest in those treated with Prednisolone plus Interferon. Children who had elevated hepatic transaminase enzymes prior to treatment or during Prednisolone priming had a better response. In contrast to many European studies, no child cleared HBsAg and produced anti-HBs. Treatment with Prednisolone priming and Interferon, improved both the time and rate of seroconversion compared to no treatment or Interferon alone, suggesting that this combination of drugs might have an immunomodulatory effect.

Hallett RL, Ngui SL, Meigh RE, Mutton KJ, Boxall EH, Teo CG. · Sexually Transmitted and Blood Borne Virus Laboratory, Health Protection Agency Colindale, London, United Kingdom. · Clin Infect Dis. · Pubmed #15472844 No free full text.

Abstract: BACKGROUND: Outbreaks of acute hepatitis B among inmates of 6 prisons in 3 regions of northern England occurring from 1992 through 1994 were found to be associated with a single hepatitis B virus (HBV) variant, which was carried by 20 of the 24 case patients. We instigated a study of cases of acute hepatitis B to trace the spread and prevalence of this variant. METHODS: A denaturing gradient gel electrophoresis assay was optimized to detect the HBV variant, and cases of acute HBV infection in 3 regions in England occurring from 1990 through 1996 were screened for its presence. Samples from HBV-transmission incidents that were received for molecular investigation were also tested. RESULTS: The variant was identified in 117 (41%) of the 266 cases of acute hepatitis examined in representative regions in England. In North Humberside, but not in southeast England or the West Midlands, a trend toward an increase in the prevalence of the variant was observed. Furthermore, the same variant was identified in the case patients or the individuals implicated in transmission in 11 (22%) of 51 transmission incidents occurring in England from 1997 through 2002. The spread of the variant was primarily associated with injection drug use. CONCLUSIONS: The finding of a single, genetically identical variant (over the 600 bp sequenced) occupying a large niche among the circulating viruses was unexpected. This finding has major implications for the use of DNA sequencing analysis in the investigation of chains of transmission. The study also highlights the need for better protection of at-risk groups through vaccination against HBV, a strategy that currently achieves poor coverage.

Boxall EH, Smith N. · National Blood Service, Vincent Drive, Edgbaston, Birmingham B15 2SG, UK. · J Public Health (Oxf). · Pubmed #15454598 links to  free full text

Abstract: BACKGROUND: The UK Department of Health recommends that all pregnant women are offered screening for infection with human immunodeficiency virus (HIV) and had encouraged maternity units to achieve uptake targets of 90 per cent by the end of 2002. Many maternity units fail to meet this target and there is concern that those women who are still refusing testing may include a higher proportion of women at high risk of infection. In consequence, those infected with HIV are not being identified and are not receiving the antiviral treatment, which would be of benefit to them and reduce the risk of transmission of HIV to their babies. METHODS: A retrospective audit of HIV screening uptake in women who were found to be infected with hepatitis B virus (HBV) and in those who were not infected with HBV was carried out in order to explore further the characteristics of 'acceptors' and 'refusers' of HIV screening. RESULTS: The overall uptake rate of HIV screening in the West Midlands population served by the National Blood Service was 60 per cent in 2001 and 74 per cent in 2002. The prevalence of HBV infection was found to be twice as high (0.39 per cent) in those who had refused an HIV test compared with those who had accepted a test (0.21 per cent) (p = 0.022). CONCLUSION: There is good evidence that women refusing HIV antenatal screening have a higher prevalence of another blood-borne virus, indicating clearly that further effort must be made to increase the screening uptake and fully integrate HIV screening with other antenatal tests.

Boxall EH, A Sira J, El-Shuhkri N, Kelly DA. · Health Protection Agency, West Midlands Public Health Laboratory, Heartlands Hospital, Birmingham, United Kingdom. · J Infect Dis. · Pubmed #15346336 No free full text.

Abstract: BACKGROUND: The long-term response to hepatitis B vaccination during infancy has not been fully evaluated in countries where endemicity is low. METHODS: The present study was a serological investigation of immunity to hepatitis B during adolescence. In a cohort of children who were born to hepatitis B virus carrier mothers and who were vaccinated during infancy, evidence of past or current infection and the response to a single booster dose of vaccine were analyzed. Sixty-four children whose antibody levels were measured after immunization (group 1) and 52 younger siblings who did not undergo postvaccination antibody tests (group 2) were studied. RESULTS: One child in each group showed evidence of natural infection. In group 1, 32 children (50%) had undetectable antibody to hepatitis B surface antigen (anti-HBs), and only 8 (13%) had levels >100 mIU/mL. After a booster dose of vaccine, only 7 (11%) still had undetectable anti-HBs, 3 (5%) showed a primary response, and 50 (78%) had levels >100 mIU/mL. Five of the 7 vaccine nonresponders and all of the primary responders had also received hepatitis B-specific immunoglobulin (HBIG) at birth. The children in group 2 showed a similar response to the vaccine, but with slightly higher levels of anti-HBs. CONCLUSIONS: Most children vaccinated at birth retain immunological memory to hepatitis B vaccine for 15 years, but those who did not were more likely to have received HBIG at birth, suggesting that passive antibody may interfere with the induction of immunological memory.

Boxall EH, Sira J, Standish RA, Davies P, Sleight E, Dhillon AP, Scheuer PJ, Kelly DA. · The Liver Unit, Birmingham Children's Hospital NHS Trust, Birmingham, UK. · Arch Dis Child Fetal Neonatal Ed. · Pubmed #15321970 links to  free full text

Abstract: OBJECTIVES: To establish natural seroconversion rates and incidence of hepatic pathology in perinatally infected hepatitis B carriers. METHODS: Seventy three perinatally infected hepatitis B carriers identified through maternal screening were evaluated. Fifty three were born to parents from the Indian subcontinent, nine were Oriental, six were Afro-Caribbean, and five were white. Median follow up was 10.24 (range 2.02-20.16) years. RESULTS: Only three of the children followed up had cleared hepatitis B surface antigen during this period, and 30% of the children had seroconverted to anti-HBe. Seroconversions to anti-HBe were observed in Asian (18/50) and white (4/5) children, but not in Oriental or Afro-Caribbean children. More girls (40%) than boys (23%) had seroconverted, but the difference was not significant. All children were asymptomatic with normal physical examination, growth, and development. Almost half (48%) of the hepatitis B e antigen (HBeAg) positive children had normal hepatic transaminases and liver function. Thirty five liver biopsies were performed in children with active virus replication (HBeAg or hepatitis B virus DNA positive) who were being considered for antiviral treatment as part of a clinical trial and were scored using the Ishak method. Two thirds (62%) of the children had mild hepatitis, 60% had mild fibrosis, and 18% had moderate to severe fibrosis. There was a weak correlation between histological evidence of hepatitis and hepatic transaminase activity, implying that biochemical monitoring of hepatic disease activity may be ineffective. CONCLUSIONS: These asymptomatic hepatitis B virus carrier children remain infectious in the medium to long term with notable liver pathology. They should receive antiviral treatment to reduce infectivity and to prevent further progression of liver disease. Hepatic transaminases alone are not a reliable marker of liver pathology, and liver histology is essential before consideration for antiviral treatment.

Cameron-Wilson CL, Muir P, Ballard AL, Corden S, Boxall EH, Sablon E, Stuyver L. · Department of Infectious Diseases, King's College London, St. Thomas' Campus, Lambeth Palace Road, London SE1 7EH, UK. · J Virol Methods. · Pubmed #14599684 No free full text.

Abstract: A prototype line probe assay (LiPA) for identifying hepatitis B virus (HBV) precore variants (INNO-LiPA HBV precore) was evaluated using a panel of 50 sera from 46 patients with HBV infection. The assay detected sequence variations detected commonly in the precore promoter region and in amino acid codons 28 and 29 of the precore gene. There was strong agreement between INNO-LiPA HBV precore results and those of a codon 28 point mutation assay (PMA), with identical results obtained in 40 of 43 sera (93%) typeable by both assays (kappa coefficient (kappa)=0.90). In addition, the precore codon 29 sequence identified by the INNO-LiPA HBV precore was confirmed by nucleotide sequencing in all seven samples analysed. However, the INNO-LiPA HBV precore identified precore promoter sequences much less efficiently. The prototype assay could identify codon 28/29 sequences from as little as 10 HBV genome equivalents in 10 microl serum, and in experiments using artificially prepared mixtures of variants could identify a minor component constituting 2.5% of the total viral DNA population. The INNO-LiPA HBV precore was also straightforward technically and rapid, and is therefore likely to be useful for epidemiological investigations into the prevalence, distribution and clinical significance of HBV precore variants.

Corden S, Ballard AL, Ijaz S, Barbara JA, Gilbert N, Gilson RJ, Boxall EH, Tedder RS. · Department of Virology, Public Health Laboratory, Birmingham Heartlands Hospital, UK. · J Clin Virol. · Pubmed #12727529 No free full text.

Abstract: BACKGROUND: Laboratory-based study funded by the Research and Development Division of the Department of Health to inform the decision making on guidelines for the conduct of exposure prone procedures (EPPs) by health care workers who are hepatitis B carriers. OBJECTIVES: Define the quantity and nature of hepatitis B virus (HBV) DNA in hepatitis carriers whose serum does not contain hepatitis B e antigen (HBeAg) and in surgeons previously cleared to conduct EPPs who have transmitted HBV to their patients. STUDY DESIGN: Cross-sectional survey using HBV DNA quantification, genotyping and sequencing comparing transmitting surgeons and asymptomatic carriers. RESULTS: HBV DNA could be detected and quantified in 64.5% (136 of 211) of carriers whose serum did not contain HBeAg with a median level 3.6 log(10) copies/ml (range of 5.7 log(10) copies). Pre-core mutation appeared not to affect the HBV DNA level, however, all surgeons carried codon 28 variants and transmitted these variants to their patients. The lowest HBV DNA level in a transmitting surgeon was 4 x 10(4) copies/ml. CONCLUSIONS: Pre-core mutations are common in carriers whose serum does not contain HBeAg and do not specifically identify carriers whose HBV DNA levels are high. It was possible to define a level of virus above which transmission of hepatitis B during conduct of EPPs could not be excluded.

Tedder RS, Ijaz S, Gilbert N, Barbara JA, Corden SA, Gilson RJ, Boxall EH. · Department of Virology, Royal Free and University College Medical School, London, United Kingdom. · J Med Virol. · Pubmed #12376958 No free full text.

Abstract: Anti-hepatitis Be (HBe) carriers are perceived as having low infectivity, with hepatitis B virus (HBV) DNA levels far below those seen in the HBeAg carrier. However, the temporal stability of HBV DNA in anti-HBe carriers remains poorly characterised. UK Department of Health guidelines use HBV DNA levels to define whether HBV-infected health care workers may perform exposure-prone procedures. Two samples separated by 1-23 years available from 147 carriers were analysed for precore variants and HBV DNA levels. Among 15 HBeAg carriers, HBV DNA was maintained at high levels. There was a 5 log(10) fold reduction in DNA in 11 individuals who developed anti-HBe during follow-up evaluation. Proportional changes in HBV DNA levels in anti-HBe carriers were similar to those in HBeAg carriers, although there was a trend for changes in viral DNA to be more marked in anti-HBe carriers followed up for longer periods. Closer sampling in 20 anti-HBe carriers demonstrated large fluctuations of DNA levels over short periods. Serum transaminases and precore mutant status at the outset failed to predict those in whom HBV DNA levels fluctuated. HBV DNA was below the detection threshold (<400 copies/ml) in 36 anti-HBe carriers at first sampling and remained so in all but 5 of these carriers. Twelve individuals who were previously viraemic lost detectable HBV DNA during follow-up evaluation. While HBV DNA levels are found to fluctuate in carriers, our results indicate that once below the threshold of detectability, levels are unlikely to rise. This is an important factor when assessing health care workers for exposure-prone procedures.

Gilbert N, Corden S, Ijaz S, Grant PR, Tedder RS, Boxall EH. · Department of Virology, Royal Free and University College Medical School, Windeyer Building, Cleveland Street, London W1P 6DB, UK. · J Virol Methods. · Pubmed #11742651 No free full text.

Abstract: Until recently, carriers of hepatitis B virus (HBV) were allowed to undertake exposure prone procedures providing their serum did not contain HBeAg. However, the recent description of hepatitis B transmission events occurring from HBV-infected health care workers who conduct exposure prone procedures demonstrated that the then current Department of Health guidelines needed to be revised. As part of a series of studies carried out to determine if viral load measurements are a more secure means of assessing the conduct of exposure prone procedures, the suitability of commercially available assays for HBV DNA detection and quantification were investigated. This study describes a comparative analysis on the performances of three assays each based on a different methodology. The assays included the QUANTIPLEX HBV DNA Assay (bDNA), (Chiron Diagnostics Ltd.), the AMPLICOR HBV Monitor Test, (Roche Diagnostics Systems) and the Digene Hybrid Capture System HBV DNA Assay (Digene Corporation). Calibration curves from experiments using the Eurohep ad and ay HBV DNA standard controls indicated a close correlation between the three assays over the dynamic ranges claimed by the manufacturers, although the Quantiplex assay did appear to be over-reporting. This became more apparent when testing patients undergoing anti-viral therapy where the Quantiplex assay consistently over-reported by 0.5 log(10) when compared with the Amplicor assay. The results of this study indicate that based on its dynamic range, the Amplicor HBV Monitor test is the most appropriate assay for the routine investigation of anti-HBe carriers, which will have lower levels of HBV DNA. The investigation also highlights the need for using accepted standard HBV DNA control sera. This will be essential when using an assay to establish whether health care workers who are hepatitis B carriers can be allowed to perform exposure prone procedures under the new guidelines of the UK Department of Health.

Ballard AL, Boxall EH. · Public Health Laboratory, Heartlands Hospital, Birmingham, United Kingdom. · J Med Virol. · Pubmed #11074475 No free full text.

Abstract: A point mutation assay was used to study the codon 28 and codon 1 precore mutant status of 310 chronic hepatitis B carriers (82 HBeAg positive and 228 HBeAg negative). Fourteen of 228 (6%) of HBeAg negative carriers had high levels of serum HBV DNA. Nine of these were explained by precore variants, three by core promoter variants, and two were not explained by recognised precore changes. Nested PCR detected serum HBV DNA in 36% (82/228) of HBeAg negative carriers and 63% (52/82) of these had precore variants. Four of 82 (4%) of the HBeAg positive carriers had precore variants, all as mixed mutant/wild type populations and evidence indicated that these carriers were seroconverting. Overall 23% (52/228) of HBeAg negative carriers had both serum HBV DNA and codon 1 or 28 precore mutations. A sexual transmission event from an HBeAg negative carrier with a relatively low serum HBV DNA level (10(4)-10(6) genome copies/ml) and only core promoter mutations was observed. Despite high rates of variant carriage in the antenatal sub-group perinatal transmission was not observed. The results of direct sequencing on 45 carriers validated the point mutation assay and also showed that codon 28 mutations were only seen in carriers with the genotype CCT at codon 15. For the Caucasian population a higher prevalence of codon 28 mutations (13/25 or 52%) than expected was seen. Liver biopsy data indicated that there was no link between the presence or absence of precore mutants and the severity of liver disease.

Ballard AL, Boxall EH. · Birmingham Public Health Laboratory, Birmingham Heartlands and Solihull NHS Trust, Heartlands Hospital. · Commun Dis Public Health. · Pubmed #10491871 No free full text.

Abstract: The infectivity of 310 hepatitis B carriers (among antenatal and genitourinary medicine clinic attendees, blood donors, and patients of a liver disease unit) was assessed using three different assays: chemiluminescent molecular hybridisation assay (Murex Digene), column-based solution hybridisation assay (Abbott Genostics) and in-house polymerase chain reaction (PCR). PCR was found to be at least 100 times more sensitive (1 x 10(4) copies/mL) than Murex Digene (3.2 x 10(6) copies/mL) and Abbott Genostics (3.7 x 10(7) copies/mL). Comparison of the hepatitis B e antigen (HBeAg)/anti-HBe status and hepatitis B virus (HBV) DNA level confirmed an association between these two variables. The overall detection rate of HBV DNA by Murex Digene was 28% (87/310): 89% (73/82) in the HBeAg positive group, 10% (4/40) in the HBeAg/anti HBe negative group, and 5% (10/188) in the anti-HBe positive group. The detection rate by PCR increased to 53% (163/310): 98% (80/82) in the HBeAg positive group, 38% (15/40) in the HBeAg/anti-HBe negative group, and 36% (67/188) in the anti-HBe positive group. HBV DNA detection rates by all three assays in 97 liver disease unit patients were higher, particularly in anti-HBe positive patients, than in the cohort overall, probably reflecting a higher rate of active liver disease in these patients. HBV DNA was detected at the lowest rate in the antenatal clinic group. We suggest that HBeAg negative patients who are positive by PCR but negative by either Murex Digene or Abbott Genostics are still infectious. A cut-off serum HBV DNA level of 10(4) copies/mL is proposed, below which transmission is unlikely to occur, but further studies using quantitative PCR are needed to refine the cut-off level.

Wallis DE, Boxall EH. · Walsall Health Authority, Lichfield House, Walsall WS1 1TE. · BMJ. · Pubmed #10213719 links to  free full text

This publication has no abstract.