Hepatitis C virus prevalence among men who have sex with men: a cross-sectional study in 12 Brazilian cities.

BACKGROUND: Despite the preventive policies adopted, reduction in sexually transmitted infections (STIs) among men who have sex with men (MSM) has been limited. The risk of hepatitis C virus (HCV) infection has increased among the most vulnerable population groups, including MSM. The aim of this study was to estimate the prevalence of HCV infection and to assess risky practices among MSM from 12 Brazilian cities. METHODS: This study was carried out from June to December 2016 using respondent driven sampling (RDS). Participants completed a self-administered questionnaire to collect behavioral, socioeconomic, and demographic variables. In addition, the rapid diagnostic test (RDT) for HCV was offered. Positive results were sent to Instituto Adolfo Lutz for confirmation. RESULTS: A total of 4,176 participants were recruited and 23 samples were sent for confirmation. Of these, 16 were confirmed, resulting in a prevalence of 0.7% (95% CI: 0.3%-1.7%). The Southeast region showed a prevalence of 0.9% (95% CI: 0.3-2.6), followed by the South region, with 0.6% (95% CI: 0.2-2.1). The Northeast region had a prevalence of 0.3% (95% CI: 0.1-1.0) and the Midwest 0.1% (95% CI: 0.0-0.7). No positive cases were found in the North. Single men aged 40 years or older were the majority of participants exposed to HCV. High levels of alcohol consumption, illicit drug use, irregular condom use, in addition to infection with other STIs, were associated with exposure to HCV. CONCLUSIONS: STIs continue to be important health problems in Brazil and globally. Many STIs are inapparent for many years until they bring more serious consequences. Extra investment in HCV is also warranted, given that it can be eliminated. Relying solely on clinical data to provide information about inapparent infection, especially in stigmatized populations, will make that goal more difficult to achieve. Surveillance studies, such as the one reported here need to be repeated over time to demonstrate trends and to provide information for evaluation, program and policies. Investments in the most vulnerable populations are critical to achieve the World Health Organization global health goals including the elimination of viral hepatitis by 2030.

Hepatitis B Prevalence among Men Who Have Sex with Men in Brazil.

Hepatitis B virus (HBV) is a global public health problem and requires specific prevention actions, particularly focusing on the key populations, such as men who have sex with men (MSM). We aimed at assessing the prevalence of HBV infection, among MSM, in a multicity study in Brazil. In 2016, we conducted a survey using a respondent-driven sampling methodology in 12 Brazilian cities. Rapid tests (RT) were performed on 3178 samples from those MSM. Positive results were tested for HBV DNA and sequenced. If negative for HBV DNA, samples were tested for serological markers. The prevalence rate of HBV exposure and clearance was 10.1% (95% CI: 8.1-12.6), and 1.1% (95%; CI: 0.6-2.1) were confirmed to be HBsAg-positive. Of those samples tested for anti-HBs (n = 1033), only 74.4% presented a serological profile analogous to that elicited by hepatitis B vaccination. Among HBsAg-positive samples (n = 29), 72.4% were HBV DNA-positive, and from these, 18 were sequenced. HBV genotypes A, F, and G were found in 55.5%, 38.9%, and 5.6%, respectively. This study indicates high prevalence rates of MSM HBV exposure and a low positivity index for the serological marker of HBV vaccine immunity. These findings may contribute to the discussion of strategies to prevent hepatitis B and reinforce the importance of promoting HBV vaccination in this key population.

Detection of Hepatitis E Virus Genotype 3 in Feces of Capybaras (Hydrochoeris hydrochaeris) in Brazil.

Hepatitis E virus (HEV) is an emerging zoonotic pathogen associated with relevant public health issues. The aim of this study was to investigate HEV presence in free-living capybaras inhabiting urban parks in São Paulo state, Brazil. Molecular characterization of HEV positive samples was undertaken to elucidate the genetic diversity of the virus in these animals. A total of 337 fecal samples were screened for HEV using RT-qPCR and further confirmed by conventional nested RT-PCR. HEV genotype and subtype were determined using Sanger and next-generation sequencing. HEV was detected in one specimen (0.3%) and assigned as HEV-3f. The IAL-HEV_921 HEV-3f strain showed a close relationship to European swine, wild boar and human strains (90.7-93.2% nt), suggesting an interspecies transmission. Molecular epidemiology of HEV is poorly investigated in Brazil; subtype 3f has been reported in swine. This is the first report of HEV detected in capybara stool samples worldwide.

Hepatitis B virus infection in Haemodialysis Centres from Santa Catarina State, Southern Brazil. Predictive risk factors for infection and molecular epidemiology.

BACKGROUND: Patients under haemodialysis are considered at high risk to acquire hepatitis B virus (HBV) infection. Since few data are reported from Brazil, our aim was to assess the frequency and risk factors for HBV infection in haemodialysis patients from 22 Dialysis Centres from Santa Catarina State, south of Brazil. METHODS: This study includes 813 patients, 149 haemodialysis workers and 772 healthy controls matched by sex and age. Serum samples were assayed for HBV markers and viraemia was detected by nested PCR. HBV was genotyped by partial S gene sequencing. Univariate and multivariate statistical analyses with stepwise logistic regression analysis were carried out to analyse the relationship between HBV infection and the characteristics of patients and their Dialysis Units. RESULTS: Frequency of HBV infection was 10.0%, 2.7% and 2.7% among patients, haemodialysis workers and controls, respectively. Amidst patients, the most frequent HBV genotypes were A (30.6%), D (57.1%) and F (12.2%). Univariate analysis showed association between HBV infection and total time in haemodialysis, type of dialysis equipment, hygiene and sterilization of equipment, number of times reusing the dialysis lines and filters, number of patients per care-worker and current HCV infection. The logistic regression model showed that total time in haemodialysis, number of times of reusing the dialysis lines and filters, and number of patients per worker were significantly related to HBV infection. CONCLUSIONS: Frequency of HBV infection among haemodialysis patients at Santa Catarina state is very high. The most frequent HBV genotypes were A, D and F. The risk for a patient to become HBV positive increase 1.47 times each month of haemodialysis; 1.96 times if the dialysis unit reuses the lines and filters > or = 10 times compared with haemodialysis units which reuse < 10 times; 3.42 times if the number of patients per worker is more than five. Sequence similarity among the HBV S gene from isolates of different patients pointed out to nosocomial transmission.