Hepatotropic viruses (hepatitis A, B, C, D and E) in a rural Brazilian population: prevalence, genotypes, risk factors and vaccination

BACKGROUND

People living in settlement projects represent an emergent rural population in Brazil. Data on their health is scarce and there are no data on viral hepatitis in this population. This study investigated the epidemiology of viral hepatitis A-E in residents of settlement projects in central Brazil.

METHODS

During 2011 and 2012, 923 people living in rural settlements in central Brazil were interviewed and tested to estimate the prevalence of exposure to viral hepatitis A-E, to identify the circulating hepatitis B virus (HBV)/hepatitis C virus (HCV) genotypes and risk factors for HBV exposure and to evaluate adherence to the hepatitis B vaccination series.

RESULTS

Overall, 85.9, 3.9, 0.4 and 17.3% of individuals showed evidence of exposure to hepatitis A virus (HAV), hepatitis E virus, HCV and HBV, respectively. Among HBV-DNA positive samples (n=8), subgenotypes A1 (n=3) and A2 (n=1) and genotype D/subgenotype D3 (n=4) were identified. Hepatitis D virus superinfection was detected in 0/16 HBsAg-positive participants. A total of 229 individuals showed serological evidence of HBV vaccination. In total, 442 settlers were eligible for vaccination, but only 150 individuals completed the vaccine series. All anti-HCV-positive samples (n=4) were also HCV-RNA positive and identified as subtype 1a.

CONCLUSIONS

The intermediate endemicity of HAV, the higher prevalence of HBV exposure compared with urban areas and the low compliance with HBV vaccination requires preventive measures focused on rural populations, emphasizing the need for HAV and HBV vaccination.

Prevalence of hepatitis B and D virus infection in a district of Mato Grosso, bordering Amazonas and Rondônia states

INTRODUCTION:

Brazil’s western Amazon basin has the highest prevalence of hepatitis B virus (HBV) infection in the country. Coinfection with hepatitis D virus (HDV) is also endemic. To estimate the prevalence of HBV and HDV markers in a population inhabiting the northwest portion of Mato Grosso state in the western Amazon.

METHODS:

We performed a cross-sectional study of the seroprevalence of antibodies against HBV core antigen (anti-HBc) in the Três Fronteiras District northwest of Mato Grosso. Anti-HBc-positive subjects were tested for HBV surface antigen (HBsAg). Those positive for this marker were tested for HDV antibodies. Anti-HBc-negative participants were tested for anti-HBsAg. All tests were performed by EIA.

RESULTS:

A total of 623 individuals in the community were assessed; the majority (67.6%) were male, with a mean age of 30.8 ± 15.4 years. Two hundred and fourteen individuals (34.3%) were anti-HBc-positive, and 47 (7.5%) were HBsAg carriers. Only one individual was anti-HDV-positive. Among the 409 individuals without HBV infection, 18.3% were anti-HBsAg-positive. There was no association between HBV infection and known risk factors.

CONCLUSIONS:

The study area had intermediate-to-high endemicity for HBV infection, but a low prevalence of HDV. Our serological results suggesting low vaccination-induced protection indicate a need for reinforced immunization programs in the populations of northwest Mato Grosso.

[Long-term use of lamivudine for treating chronic hepatitis B in the State of Mato Grosso]

To assess the results from lamivudine treatment (100 mg or 150 mg) for chronic hepatitis B, 34 patients were followed at a clinic in Cuiabá, Mato Grosso, Central Brazil. Among them, 21 (62%) had liver cirrhosis and 24 (70%) were HBeAg-positive. The viral genotype was determined for 18 patients, among whom genotype A was the most prevalent (12). The median follow-up was 27 months (range from 7 to 64 months). Among the total, 23 (67%) presented a biochemical response after 2 to 24 months of treatment. Among the 24 HBeAg-positive subjects, 13 (54%) became HBeAg-negative during the follow-up. Among the anti-HBe-positive patients, 70% obtained normalization of aminotransferase levels. Fourteen (41%) did not present any initial biochemical or serological response or presented breakthrough. The L180M and M204V mutations were found in six of the non-responders. Four patients died after at least 21 months of lamivudine and three patients with liver cirrhosis developed liver cancer after 24 months. From the third year onwards, complications such as digestive system hemorrhage or liver cancer started to emerge. The present findings suggest that an early response to lamivudine treatment may be associated with better control over chronic hepatitis B.

Prevalence of serological markers of hepatitis B virus in pregnant women from Paraná State, Brazil

The prevalence of hepatitis B virus (HBV) in Brazil increases from South to North but moderate to elevated prevalence has been detected in the Southwest of Paraná State. The prevalence of serological markers of HBV was evaluated in 3188 pregnant women from different counties in Paraná State and relevant epidemiological features were described. The prevalence of HBV markers in pregnant women for the state as a whole was 18.5% (95% CI = 17.2-19.9), ranging from 7.2% in Curitiba to 38.5% in Francisco Beltrão. The endemicity of HBV marker prevalence in pregnant women was intermediate in Cascavel, Foz do Iguaçu, and Francisco Beltrão, and low in Curitiba, Londrina, Maringá, and Paranaguá. Multiple logistic regression showed that HBV marker prevalence increased with age, was higher among black women, among women of Italian and German descent, and among women who had family members in neighboring Rio Grande do Sul State. Univariate analysis showed that HBV marker prevalence was also higher among women with no education or only primary education, with a lower family income and whose families originated from the South Region of Brazil. Pregnant women not having positive HBV markers (anti-HBc, HBsAg or anti-HBs detected by ELISA) corresponded to 73.7% of the population studied, implying that HBV vaccination needs to be reinforced in Paraná State. The highest prevalence was found in three counties that received the largest number of families from Santa Catarina and Rio Grande do Sul, where most immigrants were of German or Italian ascendance. This finding probably indicates that immigrants that came to this area brought HBV infection to Southwestern Paraná State.

Seroepidemiology of hepatitis B virus infection and high rate of response to hepatitis B virus Butang®vaccine in adolescents from low income families in Central Brazil

In order to evaluate the seroepidemiology and response to Butang vaccine in adolescents from low income families in Central Brazil, blood samples of 664 adolescents were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs) markers, and multiple logistical regression analysis was carried out to determine variables associated with hepatitis B virus (HBV) infection markers. further, three 20 microg Butang vaccine doses were offered to all susceptible individuals (n = 304). Among those who accepted them (n = 182), the seroresponse was evaluated in 170 individuals by quantitative anti-HBs. an overall hbv prevalence of 5.9% was found: four adolescents were HBsAg positive, 24 were anti-HBc, anti-HBs-reactive, and 11 were anti-HBc only. The analyse of risk factors showed that age 16-19 years, place of birth outside Goiás, school B and body piercing were statistically associated with HBV infection markers (p < 0.05). All 170 adolescents responded to Butang, and a geometric mean titer (gmt) of 4344 mUI/ml was obtained. these results reinforce the importance of hepatitis b vaccine in adolescents despite of the hbv regional endemicity, and suggest that three doses of 20 microg of the Butang should guarantee protective anti-hbs levels to individuals at a critical time for hepatitis b acquiring such as latter adolescence and adulthood.

A hepatite B e os movimentos migratórios no Estado de Mato Grosso, Brasil

A hepatite B é a principal causa de doença hepática na Amazônia, sendo um de seus maiores problemas de saúde pública. A partir dos anos 70, intensificou-se a migração para o sul da Amazônia. No norte do Estado de Mato Grosso, Brasil, foram identificados surtos de hepatite B comunitária e alta prevalência de seus marcadores entre os migrantes após meses da chegada. Análise de subtipos do antígeno de superfície do virus sugere que os migrantes trouxeram o agente infeccioso de suas regiões de origem. Fatores ambientais e comportamentais provavelmente facilitaram a rápida disseminação do vírus da hepatite B nessas comunidades. Dados mais recentes demonstram que a manutenção de vacinação e vigilância nas regiões mais acometidas está diminuindo a incidência da infecção. O aumento do número de casos de hepatite delta entre os portadores do vírus B no norte do Estado de Mato Grosso começa a ser detectado, provavelmente resultante do maior contato com os Estados vizinhos, que têm alta prevalência de hepatite delta.

Seroprevalence of hepatitis B virus infection in individuals with clinical evidence of hepatitis in Goiânia, Goiás. Detection of viral DNA and determination of subtypes

The presence of serological markers for hepatitis B virus (HBsAg, anti-HBc IgM and Anti-HBc total) was investigated in the serum of 1,396 individuals who had clinical suspect of hepatitis. It was observed that 50.7% of the individuals were positive and, from the total of the studied individuals, 14.5% were positive for HBsAg. From these, 8.5% were also positive for anti-HBc IgM. The analysis in relation to gender showed a higher seroprevalence index among male individuals (p < 0.0001). It was observed the occurrence of subtypes adw2 (62.7%), ayw3 (23.5%), ayw2 (9.8%) and adw4 (3.9%). The viral DNA was detected in 61 (33.9%) HBsAg positive samples and in one sample positive only for anti-HBc total. These results indicate an important incidence of the HBV infection in this population, and reinforce previous studies regarding this virus in the central west region of Brazil.

Seroprevalence of viral hepatitis in riverine communities from the Western Region of the Brazilian Amazon Basin

The western region of the Brazilian Amazon Basin has long been shown to be a highly endemic area for hepatitis B and hepatitis D viruses. Data concerning the prevalence of hepatitis C and E viruses in this region are still scarce. In this study we investigated the presence of hepatitis A, B, C, D and E viruses infection in communities that live along the Purus and Acre rivers in the states of Acre and Amazonas within the Amazon Basin. A total of 349 blood samples were collected and tested for hepatitis A-E serological markers (antibodies and/or antigens) using commercial enzyme linked immunosorbent assays. Anti-HCV positive sera were further assayed by an immunoblot. HBsAg positive sera were subtyped by immunodifusion. The overall prevalence for hepatitis A, B, C, and E were 93.7%, 66.1%, 1.7%, and 4%, respectively. A very high prevalence of delta hepatitis (66.6%) was found among HBsAg positive subjects. Hepatitis A, B and D viruses were shown to be largely disseminated in this population, while hepatitis C and E viruses infection presented low prevalence rates in this region. The analysis of risk factors for HBV infection demonstrated that transmission was closely associated with sexual activity.

Prevalence of hepatitis B and C virus markers among malaria-exposed gold miners in Brazilian Amazon

Hepatitis B and C virus markers were assessed during a survey on malaria in gold mine camps in southern Brazilian Amazon in order to identify risk factors associated to these viral diseases. The study comprised 520 subjects, most of them were gold miners. Missing subjects totaled 49 (8.6%). Among these 520, 82.9% had HBV markers and 7.1% were HBsAg positive. Previous hospitalization, surgery, sexually transmitted diseases and incarceration were quite common among surveyed people, but there is no association between total HBV markers and these factors. On other hand, HBsAg was independently associated to history of sexually transmitted diseases and history of surgery after adjustment. The most frequent HBsAg subtypes identified, adw2 (59%), predominates in populations of Northeast Brazil. The most surveyed people were immigrants coming from that area suggesting that immigrants carried HBV themselves to the study area. Immunoblot (RIBA) confirmed-anti-HCV were found in 2.1%. The only variable associated to anti-HCV in multivariate analysis was illicit intravenous drug. Lack of HCV infection in subjects with such a high HBV markers prevalence reinforces the opinion that HCV is transmitted by restricted routes when compared to HBV. Furthermore, gold miners in Amazon may be considered as a risk group for HBV infection, but not for HCV.

[Hepatitis Delta in the State of Mato Grosso, Brazil: report of 5 cases]

Five cases of hepatitis B and D superinfection in teenagers from the northernmost region of Mato Grosso State are reported. Hepatitis B is high prevalent there, but not hepatitis D. The proximity to the States of Acre and Amazonas and intense migration may be introducing the virus into the region. Necessity for the surveillance of hepatitis D in northern Mato Grosso is emphasized.

Dynamic study of HBsAg and HBeAg in saliva samples from patients with hepatitis B infection: diagnostic and epidemiological significance

Analysis of 505 cases history of patients among men with viral hepatitis demonstrates that HBV infected patients represent 68.9% of the total and that a non-parenteral rate of transmission is the most likely means of hepatitis B infection. Saliva and serum testing for the presence of specific HBV markers (HBsAg, HBeAg and HBV DNA) at different phases of the infection process were carried out to review the diagnostic and epidemiological value of saliva samples from patients with acute viral hepatitis B. The frequency of HBsAg detection by Enzyme Immune Assay (EIA) in saliva of patients in acute period was found to correlate with the frequency of its detection in serum. In early convalescence the frequency of detection of that antigen in serum (59.5% of patients) was significantly higher than in saliva (23.8%) (P < 0.001). The frequencies of HBeAg detection by EIA in saliva samples was significantly higher than that in serum samples in both acute phase (84.3% and 28.1% of patients, respectively) and in early convalescence (56.2% and 3.1% of patients, respectively). The study of frequencies of detection of these antigens in the dynamics of the disease up to the total recovery of patients (observations were carried out for the period of 60 days and longer) showed that in most patients there was a faster disappearance HBsAg from saliva than from serum. By the end of second month this antigen was detected in saliva of only 8.3% of patients whereas in serum in the same period HBsAg was detected in 33.3% of patients. HBeAg became undetectable in blood whereas HBs-antigenemia was still pronounced, and a month after the beginning of the disease it was not found in serum specimens. In saliva, HBeAg was detected in 95.8% of patients observed directly after admission. A month after the beginning of the disease it was detected in saliva of 66.7% of patients and, by the end of observation period, in 12.5% of patients recovered from viral hepatitis. HBV DNA revealed by PCR in saliva and serum of HBV-infected patients was detected in acute period not only in serum (84.6% of cases) but also in saliva (46.2% of cases). The data illustrate the diagnostic value of saliva and point to the possible role of saliva as a source of HBV infection.

Hepatitis C virus prevalence among an immigrant community to the southern Amazon, Brazil

A community-based random survey was conducted in a southern Brazilian Amazonian county aiming to investigate hepatitis C virus (HCV) infection prevalence and the association of demographic variables and lifestyle behaviours. Seven hundred eighty individuals were serologically screened with a third generation enzyme-linked immunosorbent assay to detect anti-HCV antibodies between 1994/1995. Positive samples were retested for confirmation with a line immunoassay (LIA, Inno-LIA HCV Ab III). Most of these subjects were low income and came from southern Brazilian states (65.8). Two point four percent (IC 95% 1.2%- 4.6%) of the subjects had LIA-confirmed anti-HCV antibodies reactivity. The age-specific prevalence of HCV antibodies slightly increased with age, with the highest prevalence after the age of 40 years. The results of multivariate analysis indicate a strong association between HCV antibodies and previous surgery and history of intravenous drug use. There were no apparent association with gender, hepatitis B virus markers, blood transfusion, and sexual activity. Mean time living in Amazon did not differ between confirmed and negative anti-HCV individuals. The present data point out an intermediate endemicity of HCV infection among this immigrant community to the Amazon region and that few HCV infected participants presented known risk factors.