Hepatitis C Virus among Female Sex Workers: A Cross-Sectional Study Conducted along Rivers and Highways in the Amazon Region

HCV-HIV Chronic Coinfection Prevalence in Amazon Region

Hepatitis C virus (HCV) infection is an important public health problem, especially in areas with a low human development index such as the Amazon region. This study aimed to identify the prevalence and genotypes of HCV among people living with HIV (PLWH), both neglected chronic diseases in the Amazon region. From March 2016 to June 2017, 433 PWLH were attended to at two sexually transmitted infection referral centers in the city of Belém, in the Brazilian state of Pará in the Amazon region. All individuals were submitted to testing via the rapid immunochromatographic assay (RIA) for the qualitative detection of anti-HCV antibodies. Samples with anti-HCV antibodies were evaluated by reverse transcriptase polymerase chain reaction (RT-PCR), and samples with HCV RNA were subjected to nucleotide sequencing and phylogenetic analysis. Three (0.7%) PLWH had anti-HCV antibodies, and only one (0.2%) had HCV RNA (genotype 2); of these, 31 (7.1%) self-declared to have used drugs at least one time, and 12 (2.7%) regularly use injected drugs. One participant was elderly, single, heterosexual, with a history of unprotected sex and multiple sexual partners. This study detected a low prevalence of HCV infection and recorded the presence of HCV genotype 2 for the first time among PLWH in the Brazilian Amazon.

Treponema pallidum among Female Sex Workers: A Cross-Sectional Study Conducted in Three Major Cities in Northern Brazil

Female sex workers (FSWs) are an important group of people vulnerable to sexually transmitted infections. Northern Brazil is a rural and socioeconomically underdeveloped region, with lack of epidemiological information on syphilis in key populations. This study investigated the prevalence and factors associated with exposure to Treponema pallidum among FSWs in three major cities in northern Brazil. This cross-sectional study was conducted with a convenience sample of 415 FSWs from the cities of Belém, Macapá, and Rio Branco. Blood samples and personal data were collected from January 2009 to August 2010. Rapid plasma reagin and immunoenzymatic assays were used to detect antibodies against T. pallidum. Logistic regression models were used to determine factors associated with exposure to T. pallidum. In total, 36.1% were exposed to T. pallidum, and 15.7% had active syphilis. Sexual risk behaviors, use of illicit drugs, low education, and reduced monthly income were associated with exposure to T. pallidum. The high rate of exposure to T. pallidum indicates the urgent need for measures to identify, treat, and prevent syphilis and an education program for the valuation, care, and social inclusion of FSWs in northern Brazil.

Treponema pallidum in female sex workers from the Brazilian Marajó Archipelago: prevalence, risk factors, drug-resistant mutations and coinfections

BACKGROUND

Female sex workers (FSWs) are an especially vulnerable group for syphilis and other sexually transmitted infection (STIs). This study determined the prevalence of syphilis in FSWs and factors associated with this disease in the Marajó Archipelago (northern Brazil), as well as the frequency of point mutations (A2058G and A2059G) in the 23S rRNA gene of Treponema pallidum and coinfections with hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV).

METHODS

FSWs were diagnosed using a rapid qualitative test and the isolates were evaluated for the presence of point mutations by real-time PCR. Blood samples with T. pallidum were tested for the presence of HBV, HCV and HDV by ELISA and confirmed by real-time PCR. The factors associated with syphilis were identified using Poisson regression models.

RESULTS

Overall, 41.1% FSWs tested positive for syphilis and 23.5% were infected with strains having A2058G/A2059G point mutations. HBV (23.0%) and HCV (8.1%) were detected among FSWs with syphilis. Six factors were associated with syphilis: low levels of education, reduced income, drug use, unprotected sex, a lengthy career in prostitution and a lack of regular medical check-ups.

CONCLUSIONS

These findings indicate an urgent need for implementation of effective strategies to diagnose, prevent and treat syphilis, as well as other STIs, in this Brazilian region.

Seroprevalence of HBV and HCV in female sex workers from four cities in the state of Pará, northern Brazil

Female sex workers (FSWs) represent a high vulnerability group for the acquisition of sexual and parenteral infections such as hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. The present study aimed to determine the prevalence of serological markers and risk factors associated with exposure to HBV and HCV among FSWs in the state of Pará, Brazil. A cross-sectional study using principles of the time location sampling (TLS) method was conducted in four cities (Belém, Bragança, Barcarena, and Augusto Corrêa) of the state of Pará, from 2005 to 2006. In total, 365 FSWs were interviewed using a standardized questionnaire. Blood samples were collected and tested for serological markers of exposure to HBV and HCV using an enzyme immunoassay. The overall prevalence of exposure to HBV and HCV was 36.7% and 7.7%, respectively. The prevalence of surface antigen of HBV was 3.0%. The prevalence of anti-HBc and anti-HBc+ anti-HBs antibodies were 6.3% and 27.4%. Very few (4.7%) FSWs had vaccine immunity against HBV (anti-HBs antibodies only). The prevalence of anti-HCV antibodies was 7.7%. Low monthly income, drug usage, and unprotected sex were some of the social characteristics associated with exposure to the viruses using different analysis. The seroprevalence of HBV and HCV infections among FSWs in four cities of the state of Pará is high when compared to the general population of Brazil, but similar to those found in FSWs in other nondeveloped countries. The prevalence of HBV was higher in Belém, while the prevalence of HCV was higher in the other three cities, highlighting the importance of establishing control and prevention programs to reduce the risk of acquiring these viruses in Pará.

Molecular Epidemiology of HIV-1 and HTLV-1/2 Among Female Sex Workers in Four Cities in the State of Para, Northern Brazil

Female sex workers (FSWs) represent a key population for the acquisition of sexually transmitted infections (STI) due to their social vulnerability and the risks associated with their occupation. This study was conducted to describe the sociodemographic characteristics and sexual behavior among FSWs in cities in northern Brazil, to determine the prevalence of human immunodeficiency virus 1 (HIV-1) and human T-cell lymphotropic virus (HTLV-1/2) infections and to identify the circulating subtypes of these agents in this key population. A cross-sectional study using the Time Location Sampling (TLS) method was conducted among 339 FSWs in cities in the state of Pará from 2005 to 2006. Serological and molecular tests were performed to identify infections and viral subtypes, and bivariate and multivariate analyses were conducted to identify risk factors. Most FSWs were young, single, less educated and had at least one child. The prevalence of antibodies against HIV-1 and HTLV-1 was 2.3 and 1.7%, respectively. HIV-1 subtypes B (87.5%) and F1 (12.5%) were identified among FSWs, as were Cosmopolitan subtype (1a) and Transcontinental subgroup (A). Unprotected sex and illicit drug use were associated with HIV-1 and HTLV-1 infections using bivariate and multivariate analyses, and age ≥27 years was associated only with HIV. The important information highlighted here clearly indicates that the lack of actions to control and prevent pathogens in FSWs and the lack of strategies for health promotion in key populations can further aggravate the epidemiological scenario of viral infections in remote areas with low human development indices. Neglecting these facts may be causing the spread of these two viruses and their respective subtypes in the general population of northern Brazil.

Prevalence of syphilis in female sex workers in three countryside cities of the state of Pará, Brazilian Amazon

Background

Syphilis is a sexually transmitted infection (STI) transmitted from person to person mainly by sexual intercourse or through vertical transmission during pregnancy. Female sex workers (FSWs) are exposed especially to syphilis infection, and besides all the efforts to control the spread of STIs, syphilis prevalence is still rising, mainly occurring in low-income countries. This study aimed to investigate the syphilis prevalence, demographic characteristics and sexual habits among FSWs in the Amazon region of Brazil.

Methods

A cross-sectional study was carried out including 184 FSWs from 3 countryside cities of the state of Pará, Amazon region of Brazil. A venereal disease research laboratory test and an indirect immunoenzyme assay to test antibodies against Treponema pallidum were used for screening syphilis infection, while sexual habits and demographic data information were collected through a semi-structured questionnaire. Data was analyzed comparing groups with/without syphilis. Poisson regression models were used to estimate the reasons of prevalence (RP).

Results

The overall prevalence of syphilis was 14.1% (95% CI = 9.8–17.8). FSWs had between 15 and 56 years of age, most were unmarried (65.7%), had attended less than 8 years of formal education (64.1%), had between 10 and 20 partners per week (64.1%), and reported no previous history of STIs (76.1%) and regular use of condom (52.7%). Low level of education attending up to the primary school (RP adjusted = 3.8; 95% CI = 1.4–9.2) and high frequency of anal sex during the past year (RP adjusted = 9.3; 95% CI = 3.5–28.7) were associated with a higher prevalence of syphilis.

Conclusions

A high prevalence of syphilis among FSWs in the Brazilian Amazon region was identified, showing that syphilis is more likely to be transmitted in FSW working in low-income areas, which is attributed to the low level of education. Anal intercourse was found as a risk factor associated with syphilis. Health programs focused on risk populations appear as a rational way to control syphilis spread, which is a rising problem in Brazil and in other several countries.