AIM: To evaluate the impact of mass vaccination against the hepatitis B virus (HBV) in Egypt, and to search for vaccinee asymptomatic breakthrough HBV infection and its genotype.
METHODS: Seven hundred serum samples from vaccinated children and adults (aged 2-47 years) were used for quantitative and qualitative detection of HBsAb by ELISA. Three hundred and sixty serum samples representing undetectable or low or high HBsAb were screened for markers of active HBV infection (HBsAg, HBcAb (IgG) and HBeAb by ELISA, plus HBsAg by AxSYM) and HBV-DNA genotyping by nested multiplex PCR and by DNA sequencing.
RESULTS: It was found that 65% of children aged 2-4 years, and 20.5% aged 4-13 years, as well as 45% adults were good responders to HBV vaccination mounting protective level HBsAb. Poor responders were 28%, 59.5% and 34%, and non-responders were 7%, 20% and 21% respectively, in the three studied groups. Markers of asymptomatic HBV infections were HBsAg detected by ELISA in 2.5% vs 11.39% by AxSYM. Other markers were HBcAb (IgG) in 1.38%, HBeAb in 0.83%, and HBV-DNA in 7.8%. All had HBV genotype E infection.
CONCLUSION: It is concluded that HBV vaccine is efficient in controlling HBV infection among children and adults. The vaccine breakthrough infection was by HBV genotype E. A booster dose of vaccine is recommended, probably four years after initial vaccination.
HBV vaccine evaluation; Egyptain children; Adults; Genotype E vaccine escape HBV
HBV infection is a contagious disease that may transmit vertically from mothers to their neonates or horizontally by blood products and body secretions. Over 50% of Iranian carriers have contracted the infection perinatally, making this the most likely route of transmission of HBV in Iran. This study assesses the serologic markers of HBV in children born to HBsAg positive mothers who received HBIG and 3 doses of HBV vaccine.
To evaluate the effectiveness of vaccination against HBV, a study was conducted on 95 Children, born to hepatitis B surface antigen (HBsAg)-positive mothers, who had received Hepatitis B Immune Globulin and HBV vaccines during 2004-2008. All children were tested for the presence of HBsAg, anti-HBs and anti-HB core antigen (anti-HBc).
Among an estimated 30000 pregnant women during the five year study, about 130 (0.42%) were HBV carriers. Ninety-five children from these mothers were enrolled in this study. Only one child (1.1%) was HBsAg positive, while 88.4% of children were Anti-HBs Positive. Eleven children (11.6%) were exposed to HBV as shown by the presence of anti-HBc. A significant difference was observed between the children’s age and Anti-HBs (p=0.0001).
Passive-active immunoprophylaxis of high risk babies was highly efficacious in preventing perinatal transmission of the HBV carrier state. Also, evaluation of serologic markers in HBV infected people is important for designing the strategies for disease control.
Children; HBsAg positive mothers; Hepatitis B Vaccine; Hepatitis B Immunoglobulin; Anti-HBc; Anti-HBs
To control hepatitis B virus (HBV) infection, a universal HBV vaccination program for infants was launched in Taiwan in 1984. The aim of this study was to investigate the role of B-cell and T-cell epitope variations of HBsAg and polymerase in HBV infection in vaccinated children. One hundred sixty-three sera from vaccinated children were enrolled randomly. HBV serum markers, including hepatitis B surface antigen (HBsAg) and antibodies to HBsAg (anti-HBs) and core antigen (anti-HBc), were detected by ELISA. Nucleotide sequences encoding the S and the pre-S regions of HBsAg were analyzed in all HBsAg positive sera. Five children were HBsAg positive. Sequence analysis of S, pre-S, and overlapped polymerase (P) genes showed that HBV isolates of HBsAg-positive vaccinees were variants; no G145R but G145A and other substitutions were found in the “a” determinant. Fifteen, six, and eight amino acid substitutions within B-cell and T-cell epitopes of S, pre-S, and P regions were detected, respectively. Several immune-epitope mutants, such as S45T/A, N131T, I194V, and S207N in S, were detected in all isolates. In conclusion, our results suggested that these naturally occurring immunoepitope mutants, which changed their immunogenicity leading to escape from immune response, might cause HBV infection.
The level of HBsAg in some chronic hepatitis B virus (HBV)-infected individuals may decline over time so that it is not detectable in serum.
To assess the efficacy of HBV vaccine in those who lost their HBsAg without seroconverssion to anti-HBs antibody.
Patients and Methods
From April 1993 to December 2008, of 1603 chronic HBV-infected individuals, 34 (22 men and 12 women) became HBsAg-negative in follow-up visits, with no detectable anti-HBs antibody and HBV DNA in their sera. They received HBV vaccination at 0, 1 and 6 months (case group). Fifty-two subjects (30 men and 22 women) who were negative for HBsAg, anti-HBs and anti-HBc antibody, received HBV vaccination according to the said schedule (control group). Anti-HBs antibody was assessed one month after the last dose of vaccination in the both groups.
The mean±SD age of the case and control groups was 38±12.7 and 33.4 ± 8.6 years, respectively (p = 0.07). The sex distribution between these two groups were similar (p = 0.652). The mean ± SD years of follow-up for the case group was 7.6 ± 4.5 years. Anti-HBs antibody level ≥ 10 IU/L was found in 8 (24%) subjects in the case group and in 45 (87%) in the control group (p < 0.001). The mean±SD anti-HBs antibody level in the case group was 68 ± 32.66 and in the control group 344.6 ± 38.9 IU/L (p < 0.001).
We found that nearly 24% of chronic HBsAg-positive subjects who lost their HBsAg responded to HBV and the remaining cases need to be followed for occult HBV infection.
Chronic hepatitis B; Follow-up study; HBsAg; Hepatitis B virus; Hepatitis B vaccine
Background and aims: Liver donors with serological evidence of resolved hepatitis B virus (HBV) infection (HBV surface antigen (HBsAg) negative, anti-HBV core (HBc) positive) can transmit HBV infection to recipients. In the context of organ shortage, we investigated the efficacy of hepatitis B immunoglobulin (HBIG) to prevent HBV infection, and assessed the infectious risk by polymerase chain reaction (PCR) testing for HBV DNA on serum and liver tissue of anti-HBc positive donors.
Patients: Between 1997 and 2000, 22 of 315 patients were transplanted with liver allografts from anti-HBc positive donors. Long term HBIG therapy was administered to 16 recipients. Four naive and two vaccinated patients received no prophylaxis.
Results: Hepatitis B developed in the four HBV naive recipients without prophylaxis and in none of the vaccinated subjects. Among the 16 recipients receiving HBIG, one patient with residual anti-HBs titres below 50 UI/ml became HBsAg positive. The remaining 15 remained HBsAg negative and HBV DNA negative by PCR testing throughout a 20 month (range 4–39) follow up period. HBV DNA was detected by PCR in 1/22 donor serum, and in 11/21 liver grafts with normal histology. A mean of 12 months post-transplantation (range 1–23) HBV DNA was no longer detectable in graft biopsies from patients remaining HBsAg negative.
Conclusion: Anti-HBs antibodies may control HBV replication in liver grafts from anti-HBc positive donors, without additional antiviral drugs. These grafts are thus suitable either to effectively vaccinated recipients or to those who are given HBIG to prevent HBV recurrence.
hepatitis B virus; anti-hepatitis B virus core; liver transplantation; hepatitis B virus infection; liver grafts
Occult hepatitis B infection (OBI) is a form of hepatitis in which there is an absence of detectable HBsAg, despite the presence of HBV-DNA in the peripheral blood of patients. It seems that non-effective or attenuated immune system responses against HBV lead to the development of OBI. Previous studies showed that the Fas/Fas ligand (FasL) system is an important death signaling pathway that is used by cytotoxic T lymphocytes to eradicate HBV from the liver.
To investigate polymorphisms in the -670 region of the Fas gene in those with OBI.
Patients and Methods
The plasma samples from 3700 blood donors were tested for HBsAg and anti-HBs by ELISA. The HBsAg-/anti-HBc(+) samples were selected and screened for HBV-DNA by PCR. Those with HBV-DNA were diagnosed as OBI and PCR-RFLP technique was performed to examine polymorphisms within their Fas gene.
352 (9.5%) of 3700 blood samples were HBsAg-/anti-HBc(+). HBV-DNA was detected in 57 (16.1%) of 352 HBsAg-/anti-HBc(+) samples. Therefore, 57 HBsAg-/anti-HBc+/HBV-DNA(+) patients were diagnosed as OBI. Patient and control groups had no significant differences in terms of the studied polymorphisms.
The functional polymorphisms in the promoter region of Fas gene are not associated with OBI. Therefore, it may be concluded that polymorphisms at the -670 position of the Fas gene do not have any critical effects on the immune response against HBV in OBI.
Hepatitis B infection; Fas; Polymorphism; HBsAg; HBV; DNA
Many clinicians do not encourage breastfeeding in hepatitis B virus (HBV) carriers, since HBV DNA can be detected in breast milk and breast lesions may increase exposure of infants to HBV. The aim of this study was to determine whether breastfeeding may add risk for perinatal HBV transmission.
Totally 546 children (1–7-year-old) of 544 HBV-infected mothers were investigated, with 397 breastfed and 149 formula-fed; 137 were born to HBeAg-positive mothers. All children had been vaccinated against hepatitis B but only 53.3% received hepatitis B immune globulin (HBIG). The overall prevalence of HBsAg+, HBsAg−/anti-HBc+, and anti-HBs (≥10 mIU/ml) in children was 2.4%, 3.1%, and 71.6% respectively. The HBsAg prevalence in breast- and formula-fed children was 1.5% and 4.7% respectively (P = 0.063); the difference was likely due to the higher mothers' HBeAg-positive rate in formula-fed group (formula-fed 49.0% vs. breastfed 15.9%, P<0.001). Further logistic regression analyses showed that breastfeeding was not associated with the HBV infection in the children, adjusting for the effect of maternal HBeAg status and other factors different between the two groups.
Under the recommended prophylaxis, breastfeeding is not a risk factor for mother-to-child transmission of HBV. Therefore, clinicians should encourage HBV-infected mothers to breastfeed their infants.
AIM: To detect the prevalence of anti-HAV IgG antibodies in adult multitransfused beta-thalassemic patients.
METHODS: We studied 182 adult beta-thalassemic patients and 209 controls matched for age and sex from the same geographic area, at the same time. Anti-HAV IgG antibodies, viral markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection were evaluated.
RESULTS: Anti-HAV IgG antibodies were detected more frequently in thalassemic patients (133/182; 73.1%) than in healthy controls (38/209; 18.2%, P < 0.0005). When we retrospectively evaluated the prevalence of anti-HAV IgG antibodies in 176/182 (96.7%) thalassemic patients, whose medical history was available for the previous ten years, it was found that 83 (47.2%) of them were continuously anti-HAV IgG positive, 16 (9.1%) acquired anti-HAV IgG antibody during the previous ten years, 49 (27.8%) presented anti-HAV positivity intermittently and 28 (15.9%) were anti-HAV negative continuously.
CONCLUSION: Multitransfused adult beta-thalassemic patients present higher frequency of anti-HAV IgG antibodies than normal population of the same geographic area. This difference is difficult to explain, but it can be attributed to the higher vulnerability of thalassemics to HAV infection and to passive transfer of anti-HAV antibodies by blood transfusions.
Hepatitis A virus; Anti-HAV antibodies; Beta-thalassemia; Multiple transfusions; Hepatitis C virus
Patients with HIV infection are at risk of co-infection with HBV, as the routes of transmission are shared and thus immunization with HBV vaccine could be protective in them. The aim of the present study was to assess the efficacy of recombinant vaccine in treatment-naive HIV positive patients and healthy controls, and to dissect out differences if any, in different limbs of immune response.
Forty HIV positive patients and 20 HIV negative controls, negative for HBsAg, HBsAbs and HBcAbs were vaccinated with three doses of 40μg and 20μg of vaccine respectively. Patients were divided into high CD4 and low CD4 group based on CD4+ lymphocytes of 200 and < 200/mm3 respectively. Group II consisted of healthy controls. Detection of phenotypic markers was done by flowcytometry. Cytokine estimation was done by sandwich ELISA. HBsAbs were estimated in serum by ELISA.
After vaccination, CD4+, CD8+ and CD3+ cells increased significantly in all the groups. There was no increase in NK cell activity in patients with high CD4+ lymphocytes and only a marginal increase in patients with low CD4+ lymphocytes (170 to 293/mm3) whereas a marked increase was observed in controls (252 to 490/mm3). After vaccination, although an increase in memory cells was observed in HIV positive patients, yet HBsAb levels were significantly lower than controls (P < 0.05) indicating a functional defect of memory cells in HIV/AIDS patients. Basal IFN-γ levels were also significantly lower in HIV/AIDS patients (P < 0.01). Although the levels increased after vaccination, the peak level remained lower than in controls. HBsAb titers were much lower in HIV positive patients compared to controls. (High CD4+ group: 8834 mIU/ml, low CD4+ group: 462 mIU/ml Vs. Controls: 16,906 mIU/ml). IL-4 and IL-10 were low in patients.
Despite a double dose in patients, IL-4 and IL-10, which regulate antibody response, were also lower in patients, and this together with low CD4+ counts and lack of T help, accounted for low HBsAb levels. Vaccination in patients with CD4+ lymphocytes < 50/mm3 was ineffective. Thus early immunization is advocated in all HIV positive patients at a stage when they are still capable of mounting an adequate immune response
Presence of occult hepatitis B infection (OBI) renders HBs antigen (HBsAg) undetectable by ELISA. Therefore it is valuable to evaluate the frequency of OBI among healthy blood donors to improve and perhaps change the strategies of blood screening to reduce the risk of HBV transmission.
The aim of this study was to determine the presence of HBcAb and HBV DNA among Iranian HBsAg negative healthy blood donors who donated their blood to the Tehran Blood Transfusion Center during 2011.
Patients and Methods
1000 serum specimens negative for HBsAg, HCV antibody and HIV antibody were collected from healthy blood donors and tested for HBcAb. Presence of hepatitis B viral DNA was checked in HBcAb positive samples by nested PCR with two sets of primers to amplify part of HBV S gene.
There were 64 women and 936 men in the population under study. The mean ± SD age of the donors was 38 ± 11 years. 80 out of 1000 samples (8%) were found to be positive for HBcAb. HBV DNA was detected in 50% of HBcAb positive specimens. The mean ± SD age of donors without HBV DNA was 37.7 ± 10.5 years and for donors with HBV DNA was 40.9 ± 11.2 years (P = 0.05).
OBI was prevalent among 50% of HBcAb positive healthy blood donors. The frequency of positive HBcAb among healthy HBsAg negative blood donors was comparable to previous studies reported from Iran. On the other hand, the frequency of HBV DNA in HBsAg negative blood donors was higher than previous reports.
Hepatitis B virus; Blood Donors; Polymerase Chain Reaction; Hepatitis B Surface Antigens
Background & Aim
Previous studies have suggested that prior exposure to hepatitis B virus (HBV) infection may increase the risk of development of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C. The aim of this study was to compare the prevalence of previous or occult HBV infection in a cohort of HBsAg-negative patients with histologically advanced chronic hepatitis C in the United States who did or did not develop HCC.
Stored sera from 91 patients with HCC and 182 matched controls who participated in the HALT-C Trial were tested for anti-HBc, anti-HBs and HBV DNA. Frozen liver samples from 28 HCC cases and 55 controls were tested for HBV DNA by real-time PCR.
Anti-HBc (as a marker of previous HBV infection) was present in the serum of 41.8% HCC cases and 45.6% controls (P=0.54); anti-HBc alone was present in 16.5% of HCC cases and 24.7% of controls. HBV DNA was detected in the serum of only one control subject and no patient with HCC. HBV DNA (as a marker of occult HBV infection) was detected in the liver of 10.7% HCC cases and 23.6% controls (P=0.18).
Although almost half the patients in the HALT-C Trial had serological evidence of previous HBV infection there was no difference in prevalence of anti-HBc in serum or HBV DNA in liver between patients who did or did not develop HCC. In the United States, neither previous nor occult HBV infection is an important factor in HCC development among patients with advanced chronic hepatitis C.
HBV DNA; hepatitis B core antibody; cirrhosis
Occult hepatitis B infection (OBI) is characterized by the presence of hepatitis B virus (HBV) DNA in the absence of HBsAg in the serum of patients. The aim of this study was to characterize HBV infection among a Piaroa community, an Amerindian group which exhibits significant evidence of exposure to HBV but relatively low presence of HBsAg, and to explore the presence of OBI in this population.
Of 150 sera, with 17% anti-HBc and 1.3% HBsAg prevalence, 70 were tested for the presence of HBV DNA. From these, 25 (36%) were found positive for HBV DNA by PCR in the core region. Two of these 25 sera were HBsAg positive, indicating an overt infection. Of the remaining 68 sera tested, 23 exhibited OBI. Of these, 13 were HBV DNA out of 25 anti-HBc positive (52%) and 10 HBV DNA positive, out of 43 anti-HBc negative (23%), with a statistical significance of p = 0.03. Viral DNA and HBsAg were present intermittently in follow up sera of 13 individuals. Sequence analysis in the core region of the amplified DNA products showed that all the strains belonged to HBV genotype F3. The OBI isolates displayed 96-100% nucleotide identity between them. One isolate exhibited the co-circulation of a wild type variant with a variant with a premature stop codon at the core protein, and a variant exhibiting a deletion of 28 amino acids.
The frequency of OBI found in this Amerindian group warrants further studies in other communities exhibiting different degrees of HBV exposure.
Hepatitis B virus; Occult infection; Amerindians
The main transmission route of the hepatitis B virus (HBV) is mother to child transmission and contributes significantly to chronic HBV infection. Even though immunoprophylaxis with hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine is administrated to neonates whose mothers are hepatitis B surface antigen (HBsAg) positive, about 10% of the neonates suffer from HBV infection in their early life.
To survey chronic HBV infection among pregnant women and their infants and analyze the reason for immunoprophylaxis failure.
Serum HBsAg was tested in all pregnant women. HBVDNA and other serum HBV markers including hepatitis B e antigen (HBeAg), hepatitis B core antibody (anti-HBc) and hepatitis B surface antibody (anti-HBs) were tested among HBsAg positive pregnant women. All infants whose mothers were HBsAg positive were vaccinated with a standard immunoprophylaxis. Serum HBV markers and HBVDNA were tested among these infants at 7 months of age. HBV genotypes were analyzed among the infants and pregnant women who were HBVDNA positive.
The prevalence of HBsAg, anti-HBc and anti-HBs among 4,536 pregnant women was 5.49%, 29.65% and 58.55%, respectively. The prevalence of HBsAg, anti-HBc and anti-HBs among pregnant women older than 20 years of age was significantly different compared to pregnant women younger than 20 years of age (4.54, 5.69 and 0.61 times, prevalence older vs. younger, respectively. P<0.05, 0.01, 0.05, respectively). Among 249 HBsAg positive pregnant women, 167 (67.07%) were HBeAg positive, 204 (81.93%) were HBVDNA positive and only 37 (14.86%) had HBVDNA >107 IU/ml. Among the infants whose mothers were HBsAg positive, 214 (85.94%) infants were anti-HBs positive. There were 12 (4.82%) infants who were HBsAg and HBVDNA positive, and all 12 of these infants mothers were HBeAg positive and had HBVDNA >107 IU/ml. Genotypes B and C were present among 165 pregnant women and genotype C was present in 85 pregnant women. There were 12 infants who were HBsAg positive and had the same HBV genotypes as their mothers. There was a significant difference in genotypes between the pregnant women whose infants were infected with HBV compared to those without HBV infection (P < 0.05).
There was a significant decline in HBsAg prevalence among pregnant women and their infants in Shenyang. Genotype C might be a risk factor for mother to child transmission of HBV.
HBV; Infection; Pregnancy; Mother to child transmission
The administration of hepatitis B immunoglobulin followed by hepatitis B vaccine can result in a protective efficacy of almost 90% in mother-to-child transmission of hepatitis B virus (HBV). However, little is known about immunity against HBV infection in children after immunoprophylactic treatment. We tried to assess the association between T-cell responses and viremia in children after successful prophylactic treatment.
Thirteen children and their 8 HBV carrier mothers (8 families), who were positive for human leukocyte antigen (HLA)-A24, were enrolled in this study. All of the 13 children received immunoprophylactic treatment and became negative for hepatitis B surface antigen (HBsAg) after birth. HBV-specific cytotoxic T lymphocyte (CTL) responses were evaluated using IFNγ - enzyme-linked immunosorbent spot (ELISPOT) and major histocompatibility complex class I peptide pentamer assays. Serum HBV DNA was measured by real-time PCR.
Significant HBV-specific T-cell responses were detected in 2 (15%) of the 13 children by ELISPOT. However, the frequency of HLA-A24-HBV-specific CTLs was very low in both HBV carrier mothers and children using pentamers. Of the 13 children, 4 (31%) were positive for serum HBV DNA. However, the levels of serum HBV DNA were 100 copies/ml or less. One of the 2 children in whom significant HBV-specific CTL responses were detectable was positive for serum HBV DNA.
HBV core and polymerase-specific T-cell responses were detected and a low-dose viremia was observed in children after successful immunoprophylaxis treatment. Although the presence of viremia was not related to HBV-specific T-cell responses, CTLs might play a role in the control of HBV infection in children born to HBsAg-positive mothers after immunoprophylactic treatment.
Routes of transmission of hepatitis B virus (HBV)/HIV infections are similar and there is a significant rate of co-infection in patients. A study was recently carried out in NHS Fife, Scotland from February 2007 - February 2008 to estimate the prevalence of HBV/HIV co-infection, occult HBV infection and immunisation status against HBV in a cohort of patients with HIV attending the departments of infectious diseases and genitourinary medicine.
Case notes were reviewed retrospectively (n = 70). Details on patient demographics, risk category, nadir/current CD4 count, HIV viral load and vaccination history were analysed. HBV markers (HBsAg/anti-HBs/anti-HBc/HBV DNA) and alanine transaminase (ALT) levels were tested prospectively if these tests had not been carried out in the previous 12 months.
Results and Conclusion
Prevalence of HBV/HIV co-infection was 5.6% of which 2.8% of patients had occult infection and 22.9% had evidence of previous exposure. Although HBV is preventable by vaccination, only 24.2% of patients had been vaccinated against it. Improvements could therefore be made in the field of prevention with vaccination and monitoring the immune response in this cohort.
Prevalence; Immunization status; Hepatitis B Virus; HIV
Chronic infection with hepatitis B virus (HBV) arising in childhood is associated with hepatocellular carcinoma in adult life. Between 1986 and 1990, approximately 120,000 Gambian newborns were enrolled in a randomised controlled trial to assess the effectiveness of infant HBV vaccination on the prevention of hepatocellular carcinoma in adulthood. These children are now in adolescence and approaching adulthood, when the onset of sexual activity may challenge their hepatitis B immunity. Thus a booster dose in adolescence could be important to maintain long-term protection.
Fifteen years after the start of the HBV infant vaccination study, 492 vaccinated and 424 unvaccinated children were identified to determine vaccine efficacy against infection and carriage in adolescence. At the same time, 297 of the 492 infant-vaccinated subjects were randomly offered a booster dose of HBV vaccine. Anti-HBs was measured before the booster, and two weeks and 1 year afterwards (ISRCTN71271385).
Vaccine efficacy 15 years after vaccination was 67.0% against infection as manifest by anti-HBc positivity (95% CI 58.2–74.6%), and 96.6% against HBsAg carriage (95% CI 91.5–100%). 31.2% of participants had detectable anti-HBs with a GMC of 32 IU/l. For 168 boosted participants GMC anti-HBs responses were 38 IU/l prior to vaccination, 524 IU/l two weeks after boosting, and 101 IU/l after 1 year.
HBV vaccination in infants confers very good protection against carriage up to 15 years of age, although a large proportion of vaccinated subjects did not have detectable anti-HBs at this age. The response to boosting persisted for at least a year.
Hepatitis B virus (HBV) is the major cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. The global epidemiological scenario of HBV infection has been changing rapidly over the last two decades due to an effective immunization programme initiated by the World Health Organization. The objective of this study is to estimate the prevalence of HBV in apparently healthy young people and to identify the risk factors of transmission of the HBV among this population in Bangui.
Dried blood Spots from 801 adolescent high school and young adult university students were prepared by spotting a drop of whole blood (4 spots) from the same fingerprick onto Whatman filter paper. A blood sample aliquot eluted from DBS was then processed with commercial ELISA tests (Abbott Murex, Dartfort, UK) to detect HBsAg antigen, Anti-HBc and Anti-HBs antibodies).
The overall prevalence was 42.3% for antibody to hepatitis B core antigen, 15.5% for HBsAg of which 1.3% of HBsAg alone. HBV familial antecedents, sexual activity and socioeconomic conditions were the main risk factors of HBV infection encountered in the adolescents and young adults.
These results show for the first time the high prevalence of HBV in apparently healthy young people in Bangui. This high prevalence is age- and sex-independent. Transmission risk factors were a familial antecedent of HBV, no utilisation of condoms and public scholarship. To lower HBV prevalence, an adequate program of active screening and vaccination for adolescents and young adults should be implemented, along with a universal immunization program.
Sudan is a highly endemic area for hepatitis B virus (HBV), and >5% of blood donors are chronically infected. To examine potential strategies to improve HBV blood safety, 404 replacement donor samples previously screened for HBV surface antigen (HBsAg) were tested for antibody to HBV core (anti-HBc), anti-surface antigen (anti-HBs), and HBV DNA. Of 145 anti-HBc-containing samples (36%) identified, 16 retested were HBsAg positive (11%). Anti-HBs was detected in 43/77 (56%) anti-HBc-reactive samples. Six samples were HBsAg−/anti-HBc+/anti-HBs+ and contained HBV DNA, meeting the definition of occult HBV infection (OBI). OBIs had low HBV DNA loads (<10 IU/ml) and were genotype B (n = 1) or genotype D (n = 5). Pre-S/S and/or whole genome sequences were obtained from 47 randomly selected HBsAg-positive donors added to the previous 16. Genotype E was identified in 27 strains (57.5%), genotype D in 19 strains (40.5%), and genotype A2 in 1 strain (2%). Two outlier strains within genotype D ultimately were identified as recombinants of genotypes D and E with identical recombination points, suggesting circulating, infectious, recombinant strains. Anti-HBc screening does not appear to be a sustainable blood safety strategy because of the cost and the negative impact on the Sudanese blood supply, even when reduced by anti-HBs testing. Being at the junction between two main African HBV genotypes, genetic recombination occurred and became part of the molecular epidemiology of HBV in Sudan.
Background and aim
Transmission of hepatitis B virus (HBV) infection occurs in up to 87.5% of HBsAg-negative recipients of anti-HBc-positive donor livers in the absence of HBV prophylaxis. There is no standardized prophylactic regimen to prevent HBV infection in this setting. The aim of this study was to determine the long-term efficacy of nucleoside analogue to prevent HBV infection in this setting.
A retrospective study of HBsAg-negative patients receiving liver transplantation (LT) from anti-HBc-positive donors during a 10-year period.
Twenty patients were studied, mean age was 50.2 ± 8.3 years, 40% were men, and 90% were Caucasian. The median MELD score at the time of LT was 18 (12–40). None of the patients received hepatitis B immune globulin. Eighteen patients received nucleoside analogue monotherapy: 10 received lamivudine and 8 received entecavir. None of these 18 patients developed HBV infection after a median follow up of 32 (1–75) months. One patient received a second course of hepatitis B vaccine 50 months after LT with anti-HBs titer above 1,000 mIU/mL. Lamivudine was discontinued and the patient remained HBsAg negative 18 months after withdrawal of lamivudine. Two patients who were anti-HBs positive before LT were not started on HBV prophylaxis after LT; both developed HBV infection after LT.
Nucleoside monotherapy is sufficient in preventing HBV infection in HBsAg-negative recipients of anti-HBc-positive donor livers. HBV prophylaxis is necessary in anti-HBs-positive recipients of anti-HBc-positive donor livers.
Lamivudine; Entecavir; Hepatitis B immune globulin; HBV vaccine; HBV infection
Dental health care providers are at risk of infection with hepatitis B virus (HBV). Dentists can occupationally become infected with HBV through needle sticks or exposure to blood and other body fluids.
To evaluate anti-HBs antibody titer in students, professors, clinical assistants and non-clinical staff of Faculty of Dentistry, Tehran University of Medical Sciences (TUMS), and to investigate the probable correlation between the level of immunity and a number of associated factors.
Patients and Methods
230 participants who had a history of previous HBV vaccination (receiving at least two doses of HBV vaccine) and a negative history of being infected with HBV were studied. Participants' data were recorded using a checklist, and the level of antibody was measured by enzyme-linked immunosorbent assay (ELISA).
While there existed statistically significant correlations between age, occupation, smoking, complete and scheduled vaccination and time of the last vaccination with the level of anti-HBs antibody, the correlation between gender and level of the antibody was not significant. Multiple regression analysis revealed significant association between immune response and age and time of the last vaccination.
Due to the significant correlation between younger age and anti-HBs antibody titer in our study, it makes sense to establish a mandatory complete and scheduled vaccination program for all members of dental society younger than 40 years.
Hepatitis B; Antibody; Vaccination; Dental health care providers
AIM: To investigate characteristics of hepatitis B virus (HBV) implicated in HBV reactivation in patients with hematological malignancies receiving immunosuppressive therapy.
METHODS: Serum samples were collected from 53 patients with hematological malignancies negative for hepatitis B surface antigen (HBsAg) before the start of and throughout the chemotherapy course. HBV reactivation was diagnosed when the HBsAg status changed from negative to positive after the initiation of chemotherapy and/or when HBV DNA was detected by real-time detection polymerase chain reaction (RTD-PCR). For detecting the serological markers of HBV infection, HBsAg as well as antibodies to the core antigen (anti-HBc) and to the surface antigen were measured in the sera by CEIA. Nucleic acids were extracted from sera, and HBV DNA sequences spanning the S gene were amplified by RTD-PCR. The extracted DNA was further subjected to PCR to amplify the complete genome as well as the specific genomic sequences bearing the enhancer II/core promoter/pre-core/core regions (nt 1628-2364). Amplicons were sequenced directly.
RESULTS: Thirty-five (66%) of the 53 HBsAg-negative patients were found to be negative serologically for anti-HBc, and the remaining 18 (34%) patients were positive for anti-HBc. Five of the 53 (9.4%) patients with hematologic malignancies experienced HBV reactivation. Genotype D1 was detected in all five patients. Four types of mutant strains were detected in the S gene product of HBV strains and were isolated from 3 patients with HBV reactivation: T/S120, L143, and I126. HBV DNA was detected in the pretreatment HBsAg-negative samples in one of the five patients with HBV reactivation. In this patient, sequences encompassing the HBV full genome obtained from sera before the start of chemotherapy and at the time of de novo HBV hepatitis were detected and it showed 100% homology. Furthermore, in the phylogenetic tree, the sequences were clustered together, thereby indicating that this patient developed reactivation from an occult HBV infection.
CONCLUSION: Past infection with HBV is a risk factor for HBV reactivation in Egypt. Mandatory anti-HBc screening prior to chemotherapy in patients with hematological malignancies is recommended.
Hepatitis B virus; Occult infection; Reactivation; Hepatitis B surface antigen
To investigate the prevalence of occult HBV infection (OBI) among children and to characterize virology of occult HBV, we conducted an epidemiological survey.
186 HB-vaccinated infants born to HBsAg-positive mothers were included in the study. Serological tests for HBV markers were performed using commercial ELISA kits. Real-time quantitative PCR and nested PCR were used to detect HBV DNA. PCR products of the C and pre-S/S regions were sequenced and analyzed.
1.61% (3/186) infants were HBsAg positive, and 4.92% (9/183) infants were considered as occult infection. The viral load of mothers was associated with occult infection (P = 0.020). Incomplete three-dose injections of HB vaccine was associated with HBV infection (P = 0.022). Six OBI infants were positive for anti-HBs, but their titers were not greater than 100 mIU/mL. Seven isolated HBV pre-S/S sequences were obtained from nine OBI infants. Three of the sequences were genotype C, and four of the sequences were genotype C/D. Escape mutation S143L was found in the four sequences of genotype C/D. All seven sequences lacked G145R and other escape mutation in S region.
Occult HBV infection was detected in anti-HBs positive infants born to HBsAg-positive mothers in China. Occult infection was associated with absent anti-HBs or with low anti-HBs level, high maternal viral loads and escape mutations in the S gene.
The chronicity of hepatitis B virus (HBV) infection is attributed to inappropriate functioning of cell-mediated immunity. Besides the importance of measuring serum HBV DNA and HBV surface antigen (HBsAg) as markers of viral replication and exposure, respectively, studies regarding their influence on immune cell status in chronic HBV infection are still scarce. Because such studies of chronic HBV patients have not been reported for India, we attempted to evaluate the relationship between serum concentrations of HBsAg, HBV DNA, and percentage of immune cells in peripheral blood of Indian subjects with chronic HBV infection.
Thirty-one HbsAg-positive subjects were evaluated for serum HBe antigen (HBeAg), anti-HBe, and alanine transferase status by standard enzyme-linked immunosorbent assay (ELISA) and biochemical procedures. Serum HBV DNA level was determined by real-time TaqMan® polymerase chain reaction assay. Serum HBsAg level was measured by a third-generation sandwich ELISA kit. Peripheral immune cell profiling was done by multifluorometric flow cytometry analysis, for which 21 healthy subjects were included as controls.
The majority (93.5%) of the study subjects were HBeAg-negative and anti-HBeAg-positive. Mean viral load, HBsAg, and alanine transferase levels were 4.20 ± 1.96 log copies/mL, 5.98 ± 4.62 log IU/mL, and 74.5 ± 110 IU/mL, respectively. In comparison with controls, total T cell and cytotoxic T cell populations were significantly (P < 0.05) reduced in HBV-infected subjects, while the status of B cells, natural killer cells, T helper cells, and ratio of T helper to cytotoxic cells remained unaltered.
Suppression of the peripheral cytotoxic T cell population in chronic HBeAg-negative chronic HBV infection is influenced by increased viral load. Serum HBsAg concentration appeared independent of serum HBV DNA level and immune cell status. Nonelevation of natural killer cell and T helper cell numbers in subjects harboring lower to moderate HBV loads is further indicative of noninduction of innate as well as a coordinated adaptive immune response favoring chronicity of the disease.
hepatitis B virus; HBsAg quantitation; viral load; peripheral lymphocytes; chronic HBV infection
The prevalence of HIV/hepatitis B virus (HBV) co-infection in South Africa ranges from 4.8% to17% using the standard marker surface antigen (hepatitis B surface antigen, HBsAg) for chronic active HBV infection. However, sensitive molecular techniques for detecting HBV DNA in serum can detect occult HBV infection. We report the first observational prospective study of occult HBV infection in HIV-positive people in South Africa.
Five hundred and two patients attending an urban hospital were screened for HBV using serological testing for HBsAg, core antibody (anti-HBc), and surface antibody (anti-HBs). DNA was analyzed using real-time quantitative PCR to determine the HBV viral load.
Of the 502 participants, 24 (4.8%) were HBsAg- positive and 53 (10.6%) were positive for anti-HBc alone. Of these 53, screening for occult disease was carried out in 43, of whom 38 (88.4%) were positive. The mean HBV viral load was 2.8 × 104 copies/ml (range 1 ×102 to 1 × 106 copies/ml).
Combining the participants with positive HBsAg and occult HBV DNA results, the prevalence of HBV increases from 4.8% (HBsAg alone) to 12.4%. While the clinical impact of occult HBV infection is unclear, consideration should be given to changing the guidelines to recommend dual HBV therapy for the treatment of co-infected patients in the developing world.
HIV; Occult HBV; Co-infection; South Africa; Developing countries
Reactivation of hepatitis B virus (HBV) infection in patients with past infection has been described in 5% to 10% of individuals undergoing immunosuppressive therapies. No data are available to date on the outcome of patients treated by tumour necrosis factor-alpha (TNFα) inhibitors for chronic arthritis with a serological pattern of past HBV infection. The aim of our study was to monitor HBV markers in HBV surface antigen (HBsAg)-negative/anti-HBcAb-positive patients treated with a TNFα inhibitor for inflammatory arthritides.
Twenty-one HBsAg-negative/anti-HBcAb-positive patients were included. HBV serological patterns were compared with those determined before starting TNFα inhibitors. Serum HBV DNA testing by polymerase chain reaction was additionally performed. Spearman correlation analysis was used and P < 0.05 was chosen as the significance threshold.
Before starting therapy, mean anti-HBsAb titre was 725 IU/L, no patient had an anti-HBsAb titre <10 IU/L, and 18 patients had an anti-HBsAb >100 IU/L. At a mean time of 27.2 months following therapy introduction, mean anti-HBsAb titre was 675 IU/L and anti-HBsAb titre remained >100 IU/L in 17 patients. There was a strong correlation between the first and second anti-HBsAb titres (r = 0.98, P = 0.013). Moreover, no patient had an anti-HBsAb titre below 10 IU/L or HBV reactivation (HBsAg seroreversion or positive HBV DNA detection). However, the anti-HBsAb titre decreased by more than 30% in 6 patients. The mean anti-HBsAb titre at baseline was significantly lower (P = 0.006) and the mean duration of anti-TNFα therapy, although non-significant (P = 0.09), was longer in these six patients as compared to patients without a decrease in anti-HBsAb titre.
Anti-TNFα treatments are likely to be safe in patients with past hepatitis B serological pattern. However, the significant decrease of anti-HBsAb titre observed in a proportion of patients deserves HBV virological follow-up in these patients, especially in those with a low anti-HBsAb titre at baseline.