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.

Prevalence and risk factors for HIV-1 infection in people who use illicit drugs in northern Brazil

BACKGROUND

People who use illicit drugs (PWUDs) have a high risk of viral infections. To date, there is a paucity of information on HIV infection among PWUDs in remote Brazilian regions. This study determined the prevalence and factors associated with HIV-1 infection among PWUDs in northern Brazil.

METHODS

Sociodemographic, economic, drug use and health-related information were collected through interviews from a community-recruited, multi-site sample of 1753 PWUDs. The blood samples collected were tested for the presence of HIV-1 using chemiluminescence immunoassay and PCR or western blotting. Logistic regressions identified factors independently associated with HIV-1 infection.

RESULTS

In total, 266 (15.2%) PWUDs were HIV-1 positive. Hepatitis B virus and/or hepatitis C virus nucleic acid was detected in 65 (3.7%) PWUDs infected by HIV-1. The factors associated with HIV-1 infection were male gender, older age, a lower educational level and a lower income, crack cocaine use, a longer drug use history and a history of drug injection and engagement in unsafe sex, sex work and a higher number of sexual partners.

CONCLUSIONS

The current study provides unique, initial insights into HIV and co-infection status and pertinent risk factors among PWUDs in northern Brazil, with clear and diverse implications for urgently improved prevention and treatment intervention needs.

Oral HPV among people who use crack-cocaine: prevalence, genotypes, risk factors, and key interventions in a remote Northern Brazilian region

OBJECTIVES

This study estimated the prevalence, genotype distribution, and the factors associated with oral human papillomavirus (HPV) in people who use crack-cocaine (PWUCC) in a remote Brazilian region.

MATERIALS AND METHODS

This cross-sectional study used community-based snowball sampling methods for participant recruitment. Socio-demographic, economic, drug use, and health-related information was collected from 278 PWUCC in the cities of Bragança and Capanema in northern Brazil. HPV diagnosis and genotyping were performed by a real-time polymerase chain reaction. Logistic regression identified the factors independently associated with oral HPV.

RESULTS

In total, 111 (39.9%) PWUCC had HPV DNA. Several genotypes were identified, some of them with high oncogenic potential. Crack-cocaine use ≥40 months, unprotected sex, more than 10 sexual partners in the last 12 months, oral sex, exchange of sex for money or illicit drugs, oral mucosa lesions, not having access to public health services, and the absence of vaccination against HPV was all associated with HPV DNA.

CONCLUSIONS

This study identified important epidemiological characteristics of oral HPV infection among PWUCC-a highly marginalized risk population-underlining the high prevalence of oral HPV with oncogenic potential and the urgent need for control and prevention measures, especially vaccination against this virus.

CLINICAL RELEVANCE

It is necessary to understand the prevalence and risk factors of oral HPV in risk populations as people who use crack-cocaine.

Range distribution and contributions to taxonomy of Elops smithi (ELOPIFORMES: ELOPIDAE)

This study presents the first record of Elops smithi for northern Brazil. The evidence suggests this species is being misidentified incorrectly as Elops saurus in estuaries of the Western Atlantic Ocean. Here, morphological, molecular, and cytogenetic evidence identified all ladyfish specimens from one estuary in the region as E. smithi. Thus, at least Elops smithi occurs in the northern coast of Brazil and it is recommended that specimens from this region identified as E. saurus be further investigated with genetic and cytogenetic tools in order to assure a correct species identification.

Prevalence and Risk Factors for Human Immunodeficiency Virus Infection Among Female Sex Workers: Distinct Offers of Sexual Services in a Municipality of the Brazilian Amazon

This study determined the prevalence of human immunodeficiency virus (HIV) infection and its associated factors in female sex workers (FSWs) from the municipality of Bragança in the state of Pará, Brazil. A cross-sectional study using a respondent-driven sampling method was used to investigate 137 FSWs. They were interviewed using a questionnaire for the collection of data on their characteristics and risk behavior. Blood samples were collected for serological and molecular testing for HIV. Poisson regression models were used to estimate the reasons of prevalence (RP). The majority was single, young, poorly educated, had a low monthly income, and had worked in the sex trade for more than 7 years. Sexual services were offered either directly (easy identification of FSWs in street markets, town squares, street corners, bars, and gas stations) or indirectly/discretely (more complex identification of FSWs, offering services through a cryptic approach or an intermediary). Overall, 22 (16.06%) FSWs had anti-HIV-1/2 antibodies, and 21 (15.33%) also had complementary DNA-HIV. The use of illicit drugs [adjusted RP (aRP) = 3.13; 95% confidence interval (CI) = 1.27-8.41], unprotected sex (aRP = 4.09; 95% CI = 1.34-11.62), anal sex (aRP = 4.01; 95% CI = 1.37-10.15), the exemption of condoms for clients paying extra (aRP = 4.71; 95% CI = 1.52-10.89), more than 7 years working as a sex worker (aRP = 6.04; 95% CI = 1.20-16.33), low levels of education (aRP = 3.55; 95% CI = 1.15-11.02), and a lack of regular medical or gynecological examinations were all associated with HIV infection (aRP = 5.87; 95% CI = 1.26-15.71). The FSWs who offered their services indirectly suffered significantly less physical and sexual aggression, charged more for encounters, had a significantly higher monthly income, and were more likely to have undergone a medical or gynecological examination within the preceding 12 months. This study identified information relevant to the control and prevention of HIV in FSWs.

Hepatitis C virus infection status and associated factors among a multi-site sample of people who used illicit drugs in the Amazon region

BACKGROUND

Elevated rates of Hepatitis C Virus (HCV) infection have been reported in epidemiological studies with people who used illicit drugs (PWUIDs) in different Brazilian regions. In Brazil's Amazon region, studies have already identified the common use of illicit drugs among adolescents and the high prevalence of HCV infections among PWUIDs. However, all studies done with PWUIDs were conducted with small samples and within limited geographic coverage. This study determined the prevalence and risk factors for HCV infection in PWUIDs in the Amazon region, northern Brazil, as well as estimating the prevalence and factors associated with the HCV spontaneous clearance (HSC).

METHODS

This cross-sectional study accessed 1666 PWUIDs from multiple municipalities of the Amazon region. Socio-demographic, economic, drug use and health-related information were collected through interviews. Blood samples collected were tested for the presence of anti-HCV antibodies and RNA-HCV. HCV genotypes were identified by real-time polymerase chain reaction (PCR). Logistic regressions were run to identify factors independently associated with HCV infection status and HSC.

RESULTS

In total, 577 (34.6%) featured HCV antibodies, of which 384 (23.1%) had active HCV infection and 193 (11.6%) indicated HSC. Genotypes 1 (80.2%) and 3 (18.8%) were detected. HCV infection status was associated with the length of illicit drug use history, factors related to parenteral and sexual transmission, and factors of socio-economic marginalization leading to potential risk activities for HCV. HSC was associated with the ethnic (including indigenous) background of participants.

CONCLUSIONS

High levels of HCV infection were detected in PWUIDs. Genotype 1 was predominant. Intense use of illicit drugs, unprotected sexual intercourse, high number of sexual partners and social marginalization were associated with all HCV infection. HSC was associated with origin (Amazonian-born) and non-white (e.g., Black or Indigenous) of PWUIDs. These findings emphasize the need for improve HCV prevention and control services and care for PWUIDs in the Brazilian Amazon region.

Prevalence and genotyping of hepatitis B virus: a cross-sectional study conducted with female sex workers in the Marajó Archipelago, Brazil

In South America, the Amazon basin is considered an endemic area of hepatitis B virus (HBV) infection. However, epidemiological studies with vulnerable groups are scarce. Female sex workers (FSWs) are highly vulnerable to sexually transmitted infections due to a combination of their sexual behavior and socio-economic conditions. Thus, this study investigated the prevalence of HBV infections and HBV–hepatitis C virus, HBV–hepatitis D virus, HBV–HIV, and HBV–human T-lymphotropic virus co-infections among FSWs in the Marajó Archipelago, northern Brazil, as well as identifying the HBV genotypes circulating in this population. A total of 153 FSWs in 5 towns and 18 riverside communities were included in the study. The HBV infection and co-infections were diagnosed by enzyme-linked immunosorbent assay and real-time polymerase chain reaction. The HBV genotypes were detected by sequencing and were then analyzed phylogenetically. Most of the FSWs surveyed were single, young, heterosexual, and born locally, with low levels of education. Overall, 21 (13.7%) had been exposed to HBV, and HBV-DNA was detected in 13 (8.5%). Genotypes A (69.2%), D (23.1%), and F (7.7%) were detected. Seven cases of co-infections with other viruses were detected. These findings indicate a clear need for urgent measures to control the spread of HBV and other pathogens, and to promote the health of the local FSWs.

Genomic Organization of the Repetitive Sequences in Centropomus undecimalis (Perciformes, Centropomidae): Implications for Hybridization and Aquaculture Programs

The family Centropomidae includes a number of fish species of high commercial value. One of these species, Centropomus undecimalis, is a target of artisanal, industrial, and sports fisheries and has also considerable potential for captive breeding, which has led to its inclusion in several aquaculture programs. While the biology and ecology of C. undecimalis are relatively well documented, few karyological data are available on this species, and they are still scarce for other centropomids. The few chromosomal data available on this family indicate a conserved karyotype 2n = 48, but it is unclear whether the chromosome microstructure is also conserved. In this study, new cytogenetic data are presented on C. undecimalis from the Amazon coastal zone, including C-banding, Ag-NOR, in situ hybridization with repetitive DNA probes (5S and 18S ribosomal genes), and telomeric (TTAGGG)n sequences. The diploid number of the species was 2n = 48, with heterochromatic blocks in the centromeric and pericentromeric regions, as well as distal signals; the nucleolus organizer regions (NORs) were associated with the heterochromatic region. The 18S and 5S recombinant DNA (rDNA) clusters were located in the distal region of chromosome pairs 1 and 11, respectively. The similarities of the karyotype macrostructure found among the centropomid species reinforce their exceptional chromosomal stability. However, the presence of heterochromatic blocks and location of NORs suggest the occurrence of structural rearrangements, which indicates that evolutionary dynamics at the microstructural level in this group may be relatively complex and should be evaluated carefully in any study that targets the production of hybrids for aquaculture.