Distribution Of Hepatitis B Virus Genotypes Research Articles

High rates of chronic HBV genotype E infection in a group of migrants in Italy from West Africa: Virological characteristics associated with poor immune clearance.

Hepatitis B virus (HBV) genotype E almost exclusively occurs in African people, and its presence is more commonly associated with the development of chronic HBV (CHB) infection. Moreover, an epidemiological link has been found between the distribution of HBV genotype E infection and African countries with high incidences of hepatocellular carcinoma. As part of a programme for the health assessment of migrants, we evaluated 358 young African subjects for HBV infection; 58.1% (208/358) were positive for an HBV marker, and 54 (25.5%) had CHB. Eighty-one percent of the CHB subjects were infected with HBV genotype E, with a median serum HBV-DNA of 3.2 (IQR: 2.7–3.6) logIU/ml. All patients had high serum HBsAg titres (10,899 [range 5,359–20,272] IU/ml), and no correlation was found between HBsAg titres and HBV-DNA plasma levels. RT sequence analysis showed the presence of a number of immune escape mutations: strains from all of the patients had a serine at HBsAg position 140; 3 also had T116N, Y100C, and P142L+S143L substitutions; and 1 had a G112R substitution. Six (18%) patients had stop-codons at position 216. In 5 of the 9 (26.5%) CHB patients, ultrasound liver biopsy, quantification of total intrahepatic HBV-DNA and cccDNA, and RT/HBsAg sequencing were performed. The median (IQR) total intrahepatic HBV-DNA was 766 (753–1139) copies/1000 cells, and the median (IQR) cccDNA was 17 (10–27) copies/1000 cells. Correlations were observed for both total intrahepatic HBV-DNA and cccDNA with serum HBV-DNA, while no correlation was found for the HBsAg titres. A difference of 2.5/1,000 nucleotides was found in the HBsAg sequences obtained from plasma and from liver tissue, with 3 cases of possible viral anatomical compartmentalization. In conclusion, a high rate of CHB infection due to the E genotype was demonstrated in a group of immigrants from Western Africa. An analysis of the viral strains obtained showed the virological characteristics of immune escape, which may be the cause of viral replication persistence. Moreover, a fair percentage of stop codon mutations were found. The lack of correlation between HBsAg titres and plasma or intrahepatic HBV-DNA found in these subjects suggests a pathway of virus production that is not linked to HBsAg secretion. Studies with a larger number of patients with CHB due to the E genotype are advisable to corroborate these observations.

GENOTIPE DAN SUBTIPE VIRUS HEPATITIS B PENDERITA YANG TERINFEKSI KRONIK AKTIF

Chronic activivity of Hepatitis B Virus (HBV) infection can lead to liver cirrhosis or hepatocellular carcinoma. The objective of thisstudy was to know by analyzing the distribution of HBV genotypes and subtypes from hepatitis B patients suffering from chronic activehepatitis B infection in Surabaya. The HBV genotypes were determined by comparing the S gene sequences to those kept in the GeneBank. The phylogenetic tree was constructed by means of the unweighted-pair group method using arithmetic averages. Furthermore,the subtypes were deduced based on the prediction of amino acid residues 116 to 183 of HBsAg on multiple sequences alignment withClustalW2. This study involved 20 sera obtained from patients suffering chronic active hepatitis B infection. After PCR and sequencing,it was found that 13 samples could be used for sequence analysis. The results showed that all sequences were clustered into HBV genotypeB. The subtype adw2 was identified from 12 of 13 sequences, whereas one (1) belonged to ayw1. The subtype adw2 is most prevalent inIndonesia, namely in the islands of Sumatra, Java, South Kalimantan, Bali, Lombok, Ternate, and Morotai, while ayw1 is found in theislands of Nusa Tenggara and Moluccas. Based on this study, it was found that the patients with HBV subtype adw2 were from Surabaya, whereas with ayw1 was from Nusa Tenggara. It can be concluded that the HBV infected patients with chronic active hepatitis B inSurabaya have the genotype B with subtype adw2 which was originally from Surabaya, whereas, ayw1 was a patient originally fromNusa Tenggara.

Genotyping and sero-virological characterization of hepatitis B virus (HBV) in blood donors, Southern Ethiopia.

Hepatitis B virus (HBV) prevalence is highest in Sub-Saharan Africa including Ethiopia. HBV genotypes have distinct geographic distributions and play a role in course of infection and treatment management. However, in Ethiopia there is paucity of information about distribution of HBV genotypes. This study was done to determine genotype, mutation and sero-virological profiles of HBV isolates in Southern Ethiopia. Cross-sectional, laboratory based study was conducted on 103HBsAg sero-positive samples from a total of 2,237 screened blood donors. HBV serological markers and biochemical assays were done. Serum viral load was measured using quantitative real-time PCR. Partial HBV S-gene was amplified with nested PCR and sequenced. Bioinformatics tools were utilized to determine genotypes, serotypes and mutations. Of 103 HBsAg reactive serum samples, 14.6% and 70.9% were sero-positive for HBeAg and HBeAb, respectively. Ninety-eight samples gave detectable viral load with a median of 3.46(2.62–4.82) log IU/ml. HBeAg sero-positive donors carried elevated levels of viral load. Eighty five isolates were successfully amplified, sequenced and genotyped into 58 (68.2%) genotype A (HBV/A) and 27 (31.8%) genotype D (HBV/D). HBV serotypes found were adw2 (74.1%), ayw2 (24.7%), and ayw3 (1.2%). In twenty-four (28.2%) samples mutations in the major hydrophilic region (MHR) were observed. Donors infected with HBV/A had higher viral load and more frequent MHR mutation than HBV/D infected donors. This study illustrated distribution of HBV genotype A and D among blood donors in southern Ethiopia. It also demonstrated occurrence HBV variants that may influence clinical aspects of HBV infection. The study contributes in narrowing the existing gap of HBV molecular study in Ethiopia.

Distribution of hepatitis B virus genotypes in Europe and clinical implications: a review

With an estimated 15 million infected persons in Europe, hepatitis B virus (HBV) infection is still one of the leading causes of chronic liver disease and associated mortality. The HBV infection prevalence in the general population depends on the region and ranges from 0.01% in Scandinavia to 10.3% in Kyrgyzstan. The prevalence of the 10 HBV genotypes (A-J) varies among different parts of the world, with genotypes A and D being most prevalent in Europe. Other HBV genotypes are mainly imported into Europe from other parts of the world and are rarely detected. HBV genotypes influence the clinical outcome of HBV infection, HBeAg seroconversion rates, and the frequency of mutations in the pre-core and core promoter regions. In addition, response rates to treatment with pegylated interferon alpha vary among HBV genotypes, whereas there is no influence of HBV genotypes on treatment response when using nucleoside/nucleotide analogues. Due to recent large-scale immigration to Europe, a change in HBV genotype distribution and the consequent clinical outcome of chronic hepatitis B may be expected in the near future.

Genetic and phylogenic characterization of hepatitis B virus in the eastern part of the Democratic Republic of Congo.

Hepatitis B virus (HBV) genotypes show a distinctive geographical distribution worldwide and genotypes A, D, and E are the most frequently found in Africa. There are only limited studies on HBV genotype distribution in Democratic Republic of Congo (DRC), all done in the western part showing a vast majority of genotype E. In our study, HBV strains from South Kivu, an eastern province of the DRC, were analyzed. Sequencing of 41 serum samples from HBV infected patients revealed strains of genotype A in 40/41 (97.6%) and genotype E in 1/41 (2.4%). The phylogenetic analysis showed that nearly all genotypes A (38/40) were closely related to A1 subgenotype strains found in Rwanda, Haiti, and Martinique while only two strains attached to the A2 subgenotype cluster were isolated. The remaining genotype E case was linked to the western African E crescent. Only the I169T nucleotide substitution was observed in two genotype A samples. In conclusion, the genotype A seems to be the most predominant genotype in eastern DRC with the majority belonging to the Afro-Asian subgenotype (A1). This contrasts with the western part of DRC where genotype E is predominant. These results support the hypothesis of an East-West genotypic demarcation.

Hepatitis B virus DNA polymerase gene polymorphism based prediction of genotypes in chronic HBV patients from Western India.

Hepatitis B Virus (HBV) infection is one of the major causes of liver cirrhosis, hepatocellular carcinoma and deaths due to the acute or chronic consequences worldwide. HBV is distributed into various genotypes based on nucleic acid sequence variation. To develop a method of HBV genotyping and drug resistance interpretation using partial sequencing of polymerase gene. This study was performed on 98 HBV infected patients' serum samples from Western India. A nested PCR protocol was designed for amplification of pol gene from HBV genome and Sanger's sequencing of the gene fragment. Sequences were aligned with HBV reference sequences for phylogenetic analysis and for characterization of genetic diversity. Drug resistance mutations were screened using HBVSeq program from Stanford University. Distribution of HBV genotypes showed predominance of genotype D, circulating in 76 (77.55%) patients (p < 0.05). Genotypes A and C were less prevalent and were identified in 4 (4.08%) and 18 (18.37%) patients, respectively. Anti-retroviral drug resistance mutations were not detected in any patient. A method for determination of HBV genotypes using pol gene sequencing which simultaneously detects major drug resistance mutations has been established. HBV genetic diversity may play an important role in treatment decision.

High prevalence of HBV infection, detection of subgenotypes F1b, A2, and D4, and differential risk factors among Mexican risk populations with low socioeconomic status.

Hepatitis B virus (HBV) infection may be underestimated among high-risk individuals in regions of low HBs antigenemia. This study aimed to assess HBV serological markers, genotypes, and risk factors in Mexican patients with risk of HBV infection and low socioeconomic status. Demographics, clinical, and risk factor data were collected in patients with HIV (n = 289), HCV (n = 243), deferred blood donors (D-BD) (n = 83), and two native populations, Mixtecos (n = 57) and Purepechas (n = 44). HBV infection was assessed by HBsAg, anti-HBc, and HBV-DNA testing. Overall, patients had low education and very-low income. Totally, HBsAg prevalence was 16.5% (113/684) ranging from 0.7% (HCV) to 37.3% (D-BD), while anti-HBc was 30.2% (207/684). Among 52 sequences, genotypes H (n = 34, 65.4%), G (n = 4, 7.7%), subgenotypes F1b (n = 7, 13.5%), A2 (n = 6, 11.5%), and D4 (n = 1, 1.9%) were detected. Surgeries, sexual promiscuity, and blood transfusions had a differential pattern of distribution. In HCV patients, single (OR = 5.84, 95%Cl 1.91-17.80, P = 0.002), MSM (OR = 4.80, 95%Cl 0.75-30.56, P = 0.097), and IDU (OR = 2.93, 95%CI 1.058-8.09, P = 0.039) were predictors for HBV infection. While IDU (OR = 2.68, 95%CI 1.08-6.61, P = 0.033) and MSM (OR = 2.64, 95%CI 1.39-5.04, P = 0.003) were predictors in HIV patients. In this group, MSM was associated with HBsAg positivity (OR = 3.45, 95%CI 1.48-8.07, P = 0.004) and IDU with anti-HBc positivity (OR = 5.12, 95%CI 2.05-12.77, P < 0.001). In conclusion, testing with a combined approach of three different HBV markers, a high prevalence of HBV infection, a differential distribution of HBV genotypes, including subgenotypes F1b, A2, and D4, as well as risk factors in low-income Mexican risk groups were detected.

Nationwide overview of the distribution of hepatitis B virus genotypes in Brazil: a 1000-sample multicentre study.

The influence of hepatitis B virus (HBV) genotypes in the natural history of the disease and its response to antiviral treatment have been addressed in many studies. In Brazil, studies on HBV genotype circulation have been restricted to specific population groups and states. Here, we have conducted a nationwide multicentre study with an unprecedented sample size representing all Brazilian regions in an effort to better understand the viral variants of HBV circulating among chronic carriers. Seven HBV genotypes were found circulating in Brazil. Overall, HBV/A was the most prevalent, identified in 589 (58.7 %) samples, followed by HBV/D (23.4 %) and HBV/F (11.3 %). Genotypes E, G, C and B were found in a minor proportion. The distribution of the genotypes differed markedly from the north to the south of the country. While HBV/A was the most prevalent in the North (71.6 %) and Northeast (65.0 %) regions, HBV/D was found in 78.9 % of the specimens analysed in the South region. HBV/F was the second most prevalent genotype in the Northeast region (23.5 %). It was detected in low proportions (7 to 10 %) in the North, Central-West and Southeast regions, and in only one sample in the South region. HBV/E was detected in all regions except in the South, while monoinfection with HBV/G was found countrywide, with the exception of Central-West states. Our sampling covered 24 of the 26 Brazilian states and the Federal District and is the first report of genotype distribution in seven states. This nationwide study provides the most complete overview of HBV genotype distribution in Brazil to date and reflects the origin and plurality of the Brazilian population.

Epidemiological, Virological and Clinical Characteristics of Hepatitis B Virus Genotypes in Chronically Infected Persons in Slovenia

Background: Hepatitis B virus (HBV) genotypes have been shown to have virological, clinical, and therapeutic implications. Knowledge about HBV genotype distribution in Slovenia is scarce. This study was the first to determine various characteristics of patients with chronic HBV infection with regard to HBV genotypes at the national level. Methods: HBV genotype determination was performed on randomly selected patients out of 1,729 patients from all Slovenian regions who tested positive for HBV surface antigen (HBsAg) at the national reference laboratory for viral hepatitis between January 1997 and December 2010. Demographic, epidemiological, virological, and clinical data were extracted from the medical records and statistically analyzed with regard to HBV genotypes. Results: A total of 186 HBsAg positive patients with the mean age of 40.1 years were identified from whom, 65.1% were male. 157 (84.4%) cases presented with genotype D, 23 (12.4%) with genotype A, and 6 (3.2%) with other HBV genotypes. Sexual transmission was more significantly associated with lower odds for HBV genotype D infection compared to blood-related risk factors (P = 0.023). Genotype A was significantly more common in men who had sex with men (P = 0.043). Compared to females with genotype D, genotype A positive women presented unknown risk factors more significantly (P = 0.002). Conclusions: HBV genotype D is the most prevalent genotype in Slovenia. However, future changes might be expected due to recent massive immigrations to Europe. Routine HBV genotyping is recommended in patients with certain risk factors prior to initiation of hepatitis B treatment.

Epidemiological study of hepatitis B virus among prisoners with active tuberculosis in Central Brazil.

Due to environmental and social conditions inherent to incarceration, tuberculosis (TB) and hepatitis B virus (HBV) are major diseases among prison inmates. To determine overall and occult HBV infection (OBI) prevalence rates, risk factors and genotype distribution among inmates with active TB. A cross-sectional study was conducted among 216 inmates with active TB recruited at the largest prisons in Campo Grande, Mato Grosso do Sul, Central Brazil. The participants were interviewed and tested for the presence of serological markers for HBV infection. The overall prevalence of HBV infection (total hepatitis B core antibodies) was 10.2% (95%CI 6.2-14.2). HBV surface antigen (HBsAg) prevalence was 1.4% (3/216). HBV DNA was detected in all three HBsAg-positive samples and in 10.5% (2/19) of the anti-HBc-positive samples (OBI), giving a HBV-TB co-infection prevalence of 2.3% (5/216). A multivariate analysis of risk factors showed that history of sharing cutting instruments, length of incarceration and homosexual sex were associated with HBV infection. Our findings indicate that HBV remains an important public health concern among prison inmates and active TB-HBV co-infection needs to be addressed for effective treatment.

High risk of occult hepatitis B virus infection in leukemia patients from China.

In this study, we assessed the prevalence of overt and occult hepatitis B virus (HBV) infection among leukemia patients. Among 256 leukemia patients and 377 fracture patients (control group), we found that the hepatitis B surface-antigen-positive rate was greater in leukemia patients than in the controls (odds ratio, 2.08; p = 0.01). Moreover, the prevalence of occult HBV infection was higher in leukemia patients than in the controls (10.5% vs. 2.9%; odds ratio, 3.92; p<0.001). The HBV genotype distribution differed significantly between the leukemia and chronic hepatitis B or control groups (p < 0.001 and 0.01, respectively); specifically, genotype C was primarily observed in occult HBV infection patients with leukemia. The stop codon mutation rate or amino acid substitutions in the major hydrophilic region did not differ between the groups. Thus, the prevalence of occult hepatitis B is higher in leukemia patients, and the HBV genotype distribution differs between patients with leukemia and chronic hepatitis B virus infection.

Serological and molecular analysis on the relationships between type 2 diabetes mellitus and hepatitis B virus infection.

This study aimed to further analyze the associations between type 2 diabetes mellitus (T2DM) and hepatitis B virus (HBV) infection, and to investigate the relationships between T2DM and the mutations within the HBV major hydrophilic region (MHR). In this cross-sectional study, 3,377 persons (338 T2DM patients and 3,039 non-diabetics) were randomly selected. HBsAg detection was performed by enzyme-linked immunosorbent assay. The HBV MHR was amplified, sequenced, and analyzed by nested PCR. The seroprevalence of HBsAg was 21.30% in T2DM patients (72/338), which was significantly higher than in non-diabetics (15.53%). Compared to persons without T2DM, the proportion of T2DM patients positive for HBsAg was significantly elevated in males, people > 55 years (p = 0.039), and people with a body mass index (BMI) ≥ 24 kg/m2. Totally, 112 genotype B and 111 genotype C HBV sequences were isolated. No significant difference in HBV genotype distribution was observed between T2DM patients and non-diabetics. Compared to genotype C HBV-infected cases in non-diabetics, the amino acid substitution rates in the MHR were significantly higher in T2DM patients (p = 0.003). Moreover, seven HBV strains with stop codon mutations within the HBV S gene were identified: three from T2DM patients (5.45%) and four from non-diabetics (2.38%). In China, T2DM is significantly associated with chronic HBV infections and genotype C HBV MHR mutations. Being males, > 55 years of age, and ≥ 24 kg/m2 of BMI are the risk factors of HBV infection in T2DM patients.

Genotyping of Hepatitis B Virus by Multiplex PCR in Sistan and Baluchestan Province

Background: Hepatitis B virus (HBV) has been classified into 8 genotypes (A - H) according to at least 8% dierence in complete nu- cleotide sequences or more than 4% in S gene. Dierent genotypes of HBV have important roles in development of certain disorders as: hepatitis, cirrhosis and hepatocellular carcinoma. Therefore, knowing the distribution of HBV genotypes, have considerable impacts on treatment strategies, vaccination program, diagnosis and prevention. Objectives: This study aims to determine the prevalence of HBV genotypes in patients infected with the virus in Sistan and Baluches- tan province (south-east Iran). Patients and Methods: In this descriptive study, 163 patients infected with HBV were selected over the first 6 months (beginning from March 2012 onward). All the patients were HBsAg (hepatitis B surface antigen) and HBeAg (extracellular form of HBcAg) positive along with viral load > 10000 copies/mL. After DNA extraction from the patients' sera, viral genotypes were determined by multiplex polymerase chain reaction (PCR) using special primers for each genotype. Results: From 163 samples, 154 samples (94.5%) had D genotype which was dominant genotype; and 9 samples (5.5%) had mixed genotype of C/D. Conclusions: This study showed that in Sistan and Baluchestan, like other regions of Iran as well as Mediterranean countries, D genotype is dominant genotype. In additional, C/D mixed genotype is also seen less frequently in this province.

Hepatitis B virus genotypes among chronic hepatitis B patients reporting at Korle-Bu teaching hospital, Accra, Ghana.

IntroductionKnowledge of hepatitis B virus (HBV) genotype is an important predictive variable which might have an impact in management and treatment of patients with chronic hepatitis B infection. In Ghana very little information is available on hepatitis B genotypes. This study was conducted to determine the distribution of HBV genotypes circulating among chronic hepatitis B patients reporting at the Korle-Bu Teaching Hospital (KBTH), Accra, Ghana.MethodsBlood samples (10 ml) were collected from 250 consenting patients. DNA was extracted and amplified using polymerase chain reaction technique. Restriction fragment length polymorphism (RFLP) was used for the detection of genotypes.ResultsOut of the 250 chronic hepatitis B patients who were HBsAg positive, 91 (36.4%) were males aged 29.8 ± 9.1 and 159 (63.6%) females aged 33± 12.1 years. HBV DNA was detected in 111 (44.4%) but only 58 (52%) of these were typeable. These were classified as genotype A, 8 (7.2%); genotype D, 3 (2.7%) and genotype E, 47 (42.3%). Our results did not show any association between the infecting genotype and age (X2= 0.923; p-value=0.623) or gender (X2= 0.283, p= 0.579).ConclusionConsistent with similar studies worldwide, the results suggest that genotypes A, D and E were the genotypes circulating among chronic hepatitis B patients who reported to the Korle-Bu Teaching Hospital with genotype E being the most predominant and therefore constitutes an important public health concern. We recommend further epidemiological studies to understand the implication of genotype E in terms of disease progression and treatment.

Geographic distribution and characteristics of genotype A hepatitis B virus infection in acute and chronic hepatitis B patients in Japan.

The prevalence of sexually transmitted acute infections of the genotype A hepatitis B virus (HBV) has been increasing in Japan. Genotype A HBV is associated with an increased risk of HBV progression to chronic infection after acute hepatitis B (AHB) in adults. A nationwide survey was conducted to evaluate the geographic distribution, clinical, and virologic characteristics of genotype A AHB and chronic hepatitis B (CHB) in Japan. Five hundred seventy AHB patients were recruited between 2005 and 2010, and 3682 CHB patients were recruited between 2010 and 2011. HBV genotypes were determined for 552 and 3619 AHB and CHB patients, respectively. Clinical characteristics were compared among different genotypes in AHB and CHB patients. Genomic characteristics of HBV genotype A were examined by molecular evolutionary analysis. Hepatitis B virus genotype A was the predominant genotype for AHB between 2005 and 2010. Phylogenetic analysis showed that all strains in the AHB patients with genotype A were classified into subtype Ae. Among CHB patients, the occurrence of genotype A was 4.1%, and genotype A was spreading in young adults. In genotype A CHB patients, early stage liver diseases were predominant, although liver diseases progressed to cirrhosis or hepatocellular carcinoma in some patients. The distribution of HBV genotypes is quite different between AHB and CHB in Japanese patients. Genotype A infection is spreading in young adults of Japanese CHB patients. Sequences derived from Japanese AHB patients were identical to or closely resembled the sequences derived from other Japanese AHB patients.

Molecular epidemiology of hepatitis B virus infection in Switzerland: a retrospective cohort study.

BackgroundChronic hepatitis B virus (HBV) infection affects up to 7 % of the European population. Specific HBV genotypes are associated with rapid progression to end-stage liver disease and sub-optimal interferon treatment responses. Although the geographic distribution of HBV genotypes differs between regions, it has not been studied in Switzerland, which lies at the crossroads of Europe.MethodsIn a retrospective analysis of 465 HBV samples collected between 2002 and 2013, we evaluated the HBV genotype distribution and phylogenetic determinants, as well as the prevalence of serological evidence of hepatitis delta, hepatitis C and HIV infections in Switzerland. Baseline characteristics of patients were compared across their region of origin using Fisher’s exact test and ANOVA, and risk factors for HBeAg positivity were assessed using logistic regression.ResultsThe Swiss native population represented 15.7 % of HBV-infected patients living in Switzerland. In the overall population, genotype D was most prevalent (58.3 %), whereas genotype A (58.9 %) was the predominant genotype among the Swiss native population. The prevalence of patients with anti-HDV antibodies was 4.4 %. Patients of Swiss origin were most likely to be HBeAg-positive (38.1 %). HBV genotypes of patients living in Switzerland but sharing the same original region of origin were consistent with their place of birth.ConclusionsThe molecular epidemiology of HBV infection in Switzerland is driven by migration patterns and not by the genotype distribution of the native population. The prevalence of positive anti-HDV antibodies in our cohort was very low.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-015-1234-z) contains supplementary material, which is available to authorized users.

Phylogenetic Analysis of Hepatitis B Virus Genotypes Circulating in Different Risk Groups of Panama, Evidence of the Introduction of Genotype A2 in the Country

The Hepatitis B Virus (HBV) can cause acute or chronic infection it is also associated with the development of liver cancer, thousands of new infections occur on a yearly basis, and many of these cases are located in certain areas of the Caribbean and Latin America. In these areas, the HBV prevalence is still high which makes this virus a serious public health concern to the entire region. Studies performed in Panama suggest a complex pattern in the distribution of HBV among the country’s different risk groups. We use phylogenetic analysis in order to determine which HBV genotypes were circulating in these specific groups; for this we used a fragment of the PreS2/2 region of the HBV genome. Subsequently whole HBV genome sequences were used for Bayesian analysis of phylodynamics and phylogeography. Two main genotypes were found: genotype A (54.5%) and genotype F (45.5%). There was a difference in the distribution of genotypes according to risk groups: 72.9% of high risk groups were associated to genotype A, and 55.0% of samples of genotype F were associated to the low risk group (p<0.002). The Bayesian analysis of phylogeny-traits association revealed a statistically significant geographical association (p<0.0001) with both genotypes and different regions of the country. The Bayesian time of most recent common ancestor analysis (tMRCA) revealed a recent tMRCA for genotype A2 circulating in Panama (1997, 95% HPD: 1986—2005), when it is compared with Panamanian genotype F1c sequences (1930, 95% HPD: 1810 – 2005). These results suggest a possible change in the distribution of HBV genotypes in Panama and Latin America as a whole. They also serve to encourage the implementation of vaccination programs in high-risk groups, in order to prevent an increase in the number of new HBV cases in Latin America and worldwide.

Viral hepatitis and human immunodeficiency virus co-infections in Asia.

Hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) affect many people in Asian countries, although there are geographic differences. Both HBV and HIV (HBV/HIV) and HCV/HIV co-infections are highly prevalent in Asia. Hetero- and homosexual, injection drug use, and geographic area are strong predictors of HBV, HCV, and HIV serostatus. In HBV endemic regions, the prevalence and genotype distribution of HBV/HIV co-infection is almost comparable with that in the general population. In Japan, where HBV has low endemicity, the prevalence of HBV/HIV co-infection is approximately 10-fold higher than that in the general population, and HBV Ae is the most common subgenotype among HIV infected individuals. Highly active antiretroviral therapy (HAART) is an effective treatment for HIV/Acquired Immune Deficiency Syndrome. Lamivudine, a component of HAART, is an effective treatment for HBV, HIV, and HBV/HIV co-infection; however, cost, emerging drug resistance, antiretroviral-associated liver toxicity and liver-related morbidity due to HCV progression are particular concerns. HCV/HIV co-infection may accelerate the clinical progression of both HCV and HIV. The high prevalence of HBV/HIV and HCV/HIV co-infections in Asia underscores the need to improve prevention and control measures, as fewer evidence-based prevention strategies are available (compared with Western countries). In this review, the most recent publications on the prevalence of HBV/HIV and HCV/HIV co-infections and related issues, such as therapy and problems in Asia, are updated and summarized.

Distribution of hepatitis B virus genotypes in azerbaijani patients with chronic hepatitis B infection.

Background:Hepatitis B virus (HBV) has been classified into ten genotypes (A-J) based on genome sequence divergence, which is very important for etiological and clinical investigations. HBV genotypes have distinct geographical distributions worldwide.Objectives:The aim of this study was to investigate the distribution of HBV genotypes among Azerbaijani patients with chronic hepatitis B, came from the Republic of Azerbaijan country to Iran to receive medical care.Patients and Methods:One hundred and three patients with chronic HBV infection, referred to hospitals related to Iran University of Medical Sciences and Tehran Hepatitis Center from August 2011 to July 2014, were enrolled in this cross sectional study. About 3-milliliter of peripheral blood was taken from each patient. After viral DNA extraction, HBV genotypes were tested using the INNO-LiPA™ HBV kit (Innogenetics, Ghent, Belgium). HBV genotyping was confirmed using sequencing of hepatitis B surface antigen (HBsAg) and polymerase (pol) regions of HBV.Results:The mean age of patients was 35.9 ± 11.7 years (19-66). Of 103 patients, 72 (69.9%) were male. In the present study, the predominant HBV genotype was D (93.2%) followed by genotype A (5.8%) and concurrent infection with A and D genotypes (0.97%).Conclusions:The main and frequent HBV genotype among Azerbaijani patients with chronic hepatitis B virus infection was genotype D followed by genotype A.

Recent population expansions of hepatitis B virus in the United States.

The recent epidemic history of hepatitis B virus (HBV) infections in the United States is complex, as indicated by current disparity in HBV genotype distribution between acute and chronic hepatitis B cases and the rapid decline in hepatitis B incidence since the 1990s. We report temporal changes in the genetic composition of the HBV population using whole-genome sequences (n = 179) from acute hepatitis B cases (n = 1,206) identified through the Sentinel County Surveillance for Acute Hepatitis (1998 to 2006). HBV belonged mainly to subtypes A2 (75%) and D3 (18%), with times of their most recent common ancestors being 1979 and 1987, respectively. A2 underwent rapid population expansions in ca. 1995 and ca. 2002, coinciding with transient rises in acute hepatitis B notification rates among adults; D3 underwent expansion in ca. 1998. A2 strains from cases identified after 2002, compared to those before 2002, tended to cluster phylogenetically, indicating selective expansion of specific strains, and were significantly reduced in genetic diversity (P = 0.001) and frequency of drug resistance mutations (P = 0.001). The expansion of genetically close HBV A2 strains was associated with risk of infection among male homosexuals (P = 0.03). Incident HBV strains circulating in the United States were recent in origin and restricted in genetic diversity. Disparate transmission dynamics among phylogenetic lineages affected the genetic composition of HBV populations and their capacity to maintain drug resistance mutations. The tendency of selectively expanding HBV strains to be transmitted among male homosexuals highlights the need to improve hepatitis B vaccination coverage among at-risk adults. Hepatitis B virus (HBV) remains an important cause of acute and chronic liver disease globally and in the United States. Genetic analysis of HBV whole genomes from cases of acute hepatitis B identified from 1998 to 2006 in the United States showed dominance of genotype A2 (75%), followed by D3 (18%). Strains of both subtypes were recent in origin and underwent rapid population expansions from 1995 to 2000, indicating increase in transmission rate for certain HBV strains during a period of decline in the reported incidence of acute hepatitis B in the United States. HBV A2 strains from a particular cluster that experienced the most recent population expansion were more commonly detected among men who have sex with men. Vaccination needs to be stepped up to protect persons who remain at risk of HBV infection.