Leila Maria Moreira Beltrão Pereira

Multilevel analysis of hepatitis A infection in children and adolescents: a household survey in the Northeast and Central-west regions of Brazil

Background The objectives were to estimate the prevalence of hepatitis A among children and adolescents from the Northeast and Midwest regions and the Federal District of Brazil and to identify individual-, household- and area-levels factors associated with hepatitis A infection. Methods This population-based survey was conducted in 2004–2005 and covered individuals aged between 5 and 19 years. A stratified multistage cluster sampling technique with probability proportional to size was used to select 1937 individuals aged between 5 and 19 years living in the Federal capital and in the State capitals of 12 states in the study regions. The sample was stratified according to age (5–9 and 10- to 19-years-old) and capital within each region. Individual- and household-level data were collected by interview at the home of the individual. Variables related to the area were retrieved from census tract data. The outcome was total antibodies to hepatitis A virus detected using commercial EIA. The age distribution of the susceptible population was estimated using a simple catalytic model. The associations between HAV infection and independent variables were assessed using the odds ratio and corrected for the random design effect and sampling weight. Multilevel analysis was performed by GLLAMM using Stata 9.2. Results The prevalence of hepatitis A infection in the 5–9 and 10–19 age-group was 41.5 and 57.4%, respectively for the Northeast, 32.3 and 56.0%, respectively for the Midwest and 33.8 and 65.1% for the Federal District. A trend for the prevalence of HAV infection to increase according to age was detected in all sites. By the age of 5, 31.5% of the children had already been infected with HAV in the Northeast region compared with 20.0% in the other sites. By the age of 19 years, seropositivity was ∼70% in all areas. The curves of susceptible populations differed from one area to another. Multilevel modeling showed that variables relating to different levels of education were associated with HAV infection in all sites. Conclusion The study sites were classified as areas with intermediate endemicity area for hepatitis A infection. Differences in age trends of infection were detected among settings. This multilevel model allowed for quantification of contextual predictors of hepatitis A infection in urban areas.

Methodology of a nationwide cross-sectional survey of prevalence and epidemiological patterns of hepatitis A, B and C infection in Brazil

A population-based survey to provide information on the prevalence of hepatitis viral infection and the pattern of risk factors was carried out in the urban population of all Brazilian state capitals and the Federal District, between 2005 and 2009. This paper describes the design and methodology of the study which involved a population aged 5 to 19 for hepatitis A and 10 to 69 for hepatitis B and C. Interviews and blood samples were obtained through household visits. The sample was selected using stratified multi-stage cluster sampling and was drawn with equal probability from each domain of study (region and age-group). Nationwide, 19,280 households and ~31,000 residents were selected. The study is large enough to detect prevalence of viral infection around 0.1% and risk factor assessments within each region. The methodology seems to be a viable way of differentiating between distinct epidemiological patterns of hepatitis A, B and C. These data will be of value for the evaluation of vaccination policies and for the design of control program strategies.

IL-22 and IL-22 binding protein (IL-22BP) regulate fibrosis and cirrhosis in hepatitis C virus and schistosome infections

Interleukin (IL)‐22 acts on epithelia, hepatocytes, and pancreatic cells and stimulates innate immunity, tissue protection, and repair. IL‐22 may also cause inflammation and abnormal cell proliferation. The binding of IL‐22 to its receptor is competed by IL‐22 binding protein (IL‐22BP), which may limit the deleterious effects of IL‐22. The role of IL‐22 and IL‐22BP in chronic liver diseases is unknown. We addressed this question in individuals chronically infected with schistosomes or hepatitis C virus (HCV). We first demonstrate that schistosome eggs stimulate production of IL‐22 transcripts and inhibit accumulation of IL22‐BP transcripts in schistosome‐infected mice, and that schistosome eggs selectively stimulate production of IL‐22 in cultures of blood leukocytes from individuals chronically infected with Schistosoma japonicum. High IL‐22 levels in cultures correlated with protection against hepatic fibrosis and portal hypertension. To test further the implication of IL‐22/IL‐22BP in hepatic disease, we analyzed common genetic variants of IL22RA2, which encodes IL‐22BP, and found that the genotypes, AA, GG of rs6570136 (P = 0.003; odds ratio [OR] = 2), and CC, TT of rs2064501 (P = 0.01; OR = 2), were associated with severe fibrosis in Chinese infected with S. japonicum. We confirmed this result in Sudanese (rs6570136 GG [P = 0.0007; OR = 8.2], rs2064501 TT [P = 0.02; OR = 3.1]), and Brazilians (rs6570136 GG [P = 0.003; OR = 26], rs2064501 TC, TT (P = 0.03; OR = 11]) infected with S. mansoni. The aggravating genotypes were associated with high IL22RA2 transcripts levels. Furthermore, these same variants were also associated with HCV‐induced fibrosis and cirrhosis (rs6570136 GG, GA [P = 0.007; OR = 1.7], rs2064501 TT, TC (P = 0.004; OR = 2.4]). Conclusions: These results provide strong evidence that IL‐22 protects against and IL‐22BP aggravates liver fibrosis and cirrhosis in humans with chronic liver infections. Thus, pharmacological modulation of IL‐22 BP may be an effective strategy to limit cirrhosis. (Hepatology 2015;61:1321–1331)

The biological meaning of anti-HBC positive result in blood donors: relation to HBV-DNA and to other serological markers

In order to assess the potential risk of anti-HBc-positive blood donors for post-transfusional hepatitis and to investigate whether other HBV serological markers are capable of identifying the presence of the virus, 1000 first-time blood donors were enrolled between June and July 1997. These donors were screened using routine Brazilian blood center tests (HIV 1 and 2, HTLV 1 and 2, Chagas disease, Syphilis, HCV, HBsAg, anti-HBc and ALT ). The 120 (12%) found to be anti-HBc-positive underwent further tests: HBe, anti-HBe, anti-HBs and HBV-DNA by PCR. Ten cases were HBsAg positive and all were HBV-DNA positive by PCR. Three HBsAg-negative donors were HBV-DNA-positive. Two HBV-DNA-positive donors were also anti-HBs-positive. All the HBV-positive donors had at least one HBV marker other than anti-HBc. Anti-HBc is an important cause of blood rejection. Testing for HBsAg alone is not fully protective and anti-HBc remains necessary as a screening test. The presence of anti-HBs is not always indicative of absence of the virus. The addition of other HBV serological markers could represent an alternative in predicting the presence of the virus when compared with PCR. It is recommended that other studies should be carried out to confirm this finding.

Cost-effectiveness analysis of universal childhood hepatitis A vaccination in Brazil: Regional analyses according to the endemic context

OBJECTIVE To conduct a cost-effectiveness analysis of a universal childhood hepatitis A vaccination program in Brazil. METHODS An age and time-dependent dynamic model was developed to estimate the incidence of hepatitis A for 24 years. The analysis was run separately according to the pattern of regional endemicity, one for South+Southeast (low endemicity) and one for the North+Northeast+Midwest (intermediate endemicity). The decision analysis model compared universal childhood vaccination with current program of vaccinating high risk individuals. Epidemiologic and cost estimates were based on data from a nationwide seroprevalence survey of viral hepatitis, primary data collection, National Health Information Systems and literature. The analysis was conducted from both the health system and societal perspectives. Costs are expressed in 2008 Brazilian currency (Real). RESULTS A universal immunization program would have a significant impact on disease epidemiology in all regions, resulting in 64% reduction in the number of cases of icteric hepatitis, 59% reduction in deaths for the disease and a 62% decrease of life years lost, in a national perspective. With a vaccine price of R

High tumor necrosis factor-α/interleukin-10 ratio is associated with hepatocellular carcinoma in patients with chronic hepatitis C.

16.89 (US

Modelling the Force of Infection for Hepatitis A in an Urban Population-Based Survey: A Comparison of Transmission Patterns in Brazilian Macro-Regions

7.23) per dose, vaccination against hepatitis A was a cost-saving strategy in the low and intermediate endemicity regions and in Brazil as a whole from both health system and society perspective. Results were most sensitive to the frequency of icteric hepatitis, ambulatory care and vaccine costs. CONCLUSIONS Universal childhood vaccination program against hepatitis A could be a cost-saving strategy in all regions of Brazil. These results are useful for the Brazilian government for vaccine related decisions and for monitoring population impact if the vaccine is included in the National Immunization Program.

High Frequency of Variant Alleles of the Mannose-Binding Lectin 2 (MBL2) Gene Are Associated with Patients Infected by Hepatitis B Virus

Hepatitis C virus (HCV) is the main cause of chronic liver disease, cirrhosis and hepatocellular carcinoma (HCC) worldwide. The risk for the development of HCC increases with the severity of liver inflammation and fibrosis. The hepatic inflammation caused by HCV involves host regulatory immune response, which is mediated by cytokines with anti-viral role upon the interaction of viral polypeptides with innate and adaptive immunity. Two cytokines; tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) play key roles in the regulation of cellular immune response in HCV infection. The aim of the present study was to determine the levels of IL-10 and TNF-α, as well as the ratio of TNF-α and IL-10 serum levels in patients with HCV and HCC caused by HCV (HCC-HCV). The study included 173 patients with chronic HCV. TNF-α and IL-10 serum levels were measured by ELISA (R&D Systems, Inc.). In the present study, 54 patients presented liver mild fibrosis, 68 had severe fibrosis and 51 patients had HCC. After adjustment in the multivariate regression analysis, the following variables remained significantly associated with HCC-HCV occurrence: diabetes (p=0.012 OR 10.44 CI 1.66-65.60), IL-10 lower levels (p<0.0001 OR 0.83 CI 0.78-0.89) and TNF-α higher levels (p<0.0001 OR 1.19 CI 1.11-1.28). Individuals with HCC presented higher TNF-α/IL-10 ratio than those with fibrosis grade F4, F3 or F0+F1+F2 (p=0.0003, p<0.0001, p<0.0001, respectively). Patients with HCC were associated to higher index TNF-α/IL-10 ratio, suggesting that the unbalanced production of these cytokines may represent progression to the liver disease severity in HCV infected patients.

Population-Based Multicentric Survey of Hepatitis B Infection and Risk Factors in the North, South, and Southeast Regions of Brazil, 10-20 Years After the Beginning of Vaccination

Background This study aimed to identify the transmission pattern of hepatitis A (HA) infection based on a primary dataset from the Brazilian National Hepatitis Survey in a pre-vaccination context. The national survey conducted in urban areas disclosed two epidemiological scenarios with low and intermediate HA endemicity. Methods A catalytic model of HA transmission was built based on a national seroprevalence survey (2005 to 2009). The seroprevalence data from 7,062 individuals aged 5–69 years from all the Brazilian macro-regions were included. We built up three models: fully homogeneous mixing model, with constant contact pattern; the highly assortative model and the highly assortative model with the additional component accounting for contacts with infected food/water. Curves of prevalence, force of infection (FOI) and the number of new infections with 99% confidence intervals (CIs) were compared between the intermediate (North, Northeast, Midwest and Federal District) and low (South and Southeast) endemicity areas. A contour plot was also constructed. Results The anti- HAV IgG seroprevalence was 68.8% (95% CI, 64.8%–72.5%) and 33.7% (95% CI, 32.4%–35.1%) for the intermediate and low endemicity areas, respectively, according to the field data analysis. The models showed that a higher force of infection was identified in the 10- to 19-year-old age cohort (∼9,000 infected individuals per year per 100,000 susceptible persons) in the intermediate endemicity area, whereas a higher force of infection occurred in the 15- to 29-year-old age cohort (∼6,000 infected individuals per year per 100,000 susceptible persons) for the other macro-regions. Conclusion Our findings support the shift of Brazil toward intermediate and low endemicity levels with the shift of the risk of infection to older age groups. These estimates of HA force of infection stratified by age and endemicity levels are useful information to characterize the pre-vaccination scenario in Brazil.

Mannose-binding lectin serum levels in patients with leprosy are influenced by age and MBL2 genotypes

Patients with hepatitis B virus (HBV) infection may develop severe chronic liver disease. Carriers of HBV have an increased risk of developing cirrhosis, hepatic decompensation, and hepatocellular carcinoma. Worldwide an estimated 350 million people are infected with HBV, and 15-40% will develop serious sequelae in their lifetime. In our study we investigated the association of single nucleotide polymorphisms (SNPs) in the first exon and promoter region of the mannose-binding lectin gene 2 (MBL2) situated on chromosome 10, with susceptibility to HBV infection. One-hundred and two patients infected with HBV were included in this study, and 232 uninfected individuals were used as healthy controls. Genotyping of the first exon (alleles A/O) was performed using a melting temperature assay. Genotyping of the promoter region (-550 H/L; -221 Y/X) was performed using the Taqman PCR technique. In the HBV-infected group we found a significantly increased frequency of haplotypes associated with low serum MBL. Our findings may indicate that MBL has a protective role against HBV infection in the studied population.