Neisseria gonorrhoeae (GC) is a human pathogen that adheres to and invades genital surfaces. Although pili are required for the initial adherence, the interaction of GC with epithelial cells is also promoted by a family of outer membrane proteins, the opacity (Opa) proteins such as OpaA protein from strain MS11. Studies have demonstrated that the interaction of the OpaA GC with epithelial cells involves binding to heparan sulfate attached to syndecan receptors. However, other Opa proteins interact with CEA gene family member 1 (CGM1) or biliary glycoprotein (BGP), members of the CD66 antigen family. In this study, we demonstrate that, in addition, the 180-kD carcinoembryonic antigen (CEA) is a receptor for Opa proteins. This conclusion was based on the following observations. First, transfected HeLa cells expressing CEA (HeLaCEA) and the CEA-expressing colon cancer cell line (LS 174T) bound and subsequently engulfed the Opa+ bacteria. These interactions were inhibited by anti-CEA antibody, but could not be inhibited by addition of heparin. Furthermore, OpaI E. coli directly bound purified CEA. We also compared the adherence and invasion by Opa+ bacteria of CD66 transfected HeLa cells: HeLa-BGPa, HeLa-CGM6, HeLa-NCA, HeLa-CGM1a, HeLa-CEA, and HeLa-Neo serving as negative control. Using OpaI as the prototype, the relative ability of the transfected HeLa cell lines to support adherence was (CEA = BGPa >CGM1a >NCA >>CGM6 = Neo). The ability to mediate invasion of the transfectant cells was (CGM1a >CEA >BGPa >NCA >CGM6 = Neo). Among the Opa proteins tested, OpaC proved to be bifunctional, able to mediate adherence to both syndecan receptors and to CD66 antigens.
ObjectiveTo investigate and compare determinates for delayed first presentation to antenatal care (ANC) services.MethodsA cross-sectional study was conducted amongst pregnant women attending their first ANC visit in rural Capricorn District and peri-urban Tlokwe sub-district communities in South Africa. Data collection included questionnaires and medical record abstraction. Bivariate and multivariate analyses assessed factors associated with late ANC presentation.ResultsWe recruited 807 pregnant women. Of these, 51% of rural women and 28% of peri-urban women presented late for first ANC. Rural women were more likely to present late for first ANC (AOR = 2.65; 95% CI 1.98–3.55) and report barriers to accessing ANC services (P<0.0001). Late ANC presentation in rural communities was associated with being married (AOR = 2.36; 95% CI 1.33–4.19), employed (AOR = 1.90; 95% CI 1.03–3.50), <20 years of age (AOR = 2.19; 95% CI 1.10–4.37), and reporting an unplanned pregnancy (AOR = 2.21; 95% CI 1.40–3.50). Late presentation in peri-urban communities was associated with unplanned pregnancy (AOR = 1.67; 95% CI 1.01–2.74), being told to come back later to initiate ANC after presenting early (AOR 0.51; 95% CI 0.30–0.89) and being pregnant for the first time (AOR = 0.56; 95% CI 0.34–0.94)ConclusionBoth rural and peri-urban women had high rates of late presentation for first ANC. However, women in the rural communities were more likely to present late. Unplanned pregnancy was an independent risk factor in both rural and peri-urban communities. Interventions around family planning, especially for adolescent girls and young women, are needed to improve early presentation for ANC.
There is a lack of evidence on the burden of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) among HIV-infected pregnant women in South Africa. We conducted a cross-sectional analysis of HIV-infected pregnant women in two healthcare facilities in a South African township to determine the prevalence of CT, NG and TV. HIV-infected pregnant women were recruited during the first antenatal care visit for their current pregnancy and requested to self-collect vulvovaginal swab specimens. Specimens were tested for CT, NG and TV using the Xpert® assay (Cepheid, Sunnyvale, CA). Of 247 tested for CT, NG and TV, 47.8% tested positive for at least one organism; CT = 36.8%, TV = 23.9%, NG = 6.9%. Forty three (17.4%) had multiple infections, of which 42 included CT as one of the infecting organisms. Of the 118 participants who tested positive for at least one sexually transmitted infection (STI), 23.7% reported STI-like symptoms. Among women who tested positive for CT, 29.7% reported symptoms while 47.1 and 27.1% of those who tested positive for NG and TV, respectively, reported symptoms. The high STI prevalence coupled with the low symptom prevalence among infected individuals justifies the use of diagnostic screening approaches rather than syndromic management of STIs in this setting.
Background: During May–June 2010, a childhood lead poisoning outbreak related to gold ore processing was confirmed in two villages in Zamfara State, Nigeria. During June–September of that year, villages with suspected or confirmed childhood lead poisoning continued to be identified in Zamfara State.Objectives: We investigated the extent of childhood lead poisoning [≥ 1 child with a blood lead level (BLL) ≥ 10 µg/dL] and lead contamination (≥ 1 soil/dust sample with a lead level > 400 parts per million) among villages in Zamfara State and identified villages that should be prioritized for urgent interventions.Methods: We used chain-referral sampling to identify villages of interest, defined as villages suspected of participation in gold ore processing during the previous 12 months. We interviewed villagers, determined BLLs among children < 5 years of age, and analyzed soil/dust from public areas and homes for lead.Results: We identified 131 villages of interest and visited 74 (56%) villages in three local government areas. Fifty-four (77%) of 70 villages that completed the survey reported gold ore processing. Ore-processing villages were more likely to have ≥ 1 child < 5 years of age with lead poisoning (68% vs. 50%, p = 0.17) or death following convulsions (74% vs. 44%, p = 0.02). Soil/dust contamination and BLL ≥ 45 µg/dL were identified in ore-processing villages only [50% (p < 0.001) and 15% (p = 0.22), respectively]. The odds of childhood lead poisoning or lead contamination was 3.5 times as high in ore-processing villages than the other villages (95% confidence interval: 1.1, 11.3).Conclusion: Childhood lead poisoning and lead contamination were widespread in surveyed areas, particularly among villages that had processed ore recently. Urgent interventions are required to reduce lead exposure, morbidity, and mortality in affected communities.
BackgroundHIV increases women’s risk for high-risk human papillomavirus (hrHPV) infection and invasive cervical cancer. South Africa has a high HIV prevalence but low cervical cancer screening coverage. Self-collection of cervical specimens and hrHPV testing, including hrHPV messenger-RNA (mRNA) testing, are methods aimed at increasing screening rates. However, data are limited on the acceptability and accuracy of tampon-based self-collection for hrHPV mRNA testing in HIV-infected women.MethodsWe recruited 325 HIV-infected women seeking care at a government HIV clinic in Pretoria, South Africa. A clinician performed a pelvic examination and obtained an endocervical specimen. Study participants performed self-collection using a tampon. Both clinician- and self-collected specimens were tested for hrHPV mRNA. Acceptability of both collection methods was assessed, the prevalence of hrHPV mRNA in our study population was estimated, test positivity of the two collection methods were compared, and test agreement was assessed by calculating the κ-statistic, sensitivity, and specificity.ResultsOver 90% of women reported no difficulties self-collecting specimens and 82% were willing to perform the tampon-collection at home. Based on clinician-collection specimens, the prevalence of hrHPV mRNA in our study population was 36.7% (95% CI: 31.4%– 42.0%). There was no difference in test positivity between clinician-collection, 36.7%, and tampon-collection, 43.5% (p-value = 0.08). Using clinician-collection as the reference test, the sensitivity and specificity for hrHPV mRNA of tampon-collection were 77.4% (95% CI: 69.8–85.0%) and 77.8% (95% CI: 71.9–83.6%), respectively.ConclusionsTampon-based self-collection is acceptable to women and has similar hrHPV mRNA positivity rates as clinician-collection, but has reduced sensitivity and specificity compared to clinician-collection. The hrHPV mRNA prevalence in our study population is high, but similar to other high-risk populations, and highlights the need for improved cervical cancer screening. Further research into the optimal use of tampon-based collection as a cervical cancer screening tool is warranted.
Background Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) infections may increase the risk of vertical transmission of the human immunodeficiency virus (HIV). In resource-limited settings, symptomatic screening, and syndromic management of sexually transmitted infections (STIs) during pregnancy continue to be the standard of care. In the absence of diagnostic testing, asymptomatic infections in pregnant women go untreated. Objective To describe the acceptability and feasibility of integrating diagnostic STI screening into first antenatal care visits for HIV-infected pregnant women. Methods HIV-infected pregnant women were recruited during their first antenatal care visit from three antenatal care clinics in Tshwane District, South Africa, between June 2016 and October 2017. Self-collected vaginal swabs were used to screen for CT, NG, and TV with a diagnostic point-of-care (POC) nucleic acid amplification test. Those with STIs were provided treatment per South African national guidelines. Results Of 442 eligible women, 430 (97.3%) agreed to participate and were tested. Of those with a positive STI test result (n = 173; 40.2%), 159 (91.9%) received same-day results and treatment; 100% of STI-infected women were treated within seven days. Conclusions Integration of POC diagnostic STI screening into first-visit antenatal care services was feasible and highly acceptable for HIV-infected pregnant women.
Low rates of TB screening and testing by the health system resulted in missed TB patients. Universal TB screening and testing of symptomatic individuals should be instituted in high TB burden communities in South Africa.
ObjectiveSTIs during pregnancy increase adverse pregnancy and birth outcomes and may increase HIV risk. STI syndromic management is standard of care in South Africa. Our study evaluated the prevalence and incidence of STIs in pregnant women and the associated risk factors.MethodsWe combined data from two prospective observational studies of pregnant women enrolled while attending their first antenatal clinic (ANC) visit in Tshwane District and Cape Town. Women ≥18 years were tested at first ANC visit and at their first postpartum visit for Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis using Xpert assays (Cepheid, USA). We evaluated the prevalence and incidence of STI and the associated risk factors using multivariable regression models.ResultsWe enrolled 669 pregnant women, 64% (n=427) from Tshwane District and 36% (n=242) from Cape Town; 80% (n=534) were women living with HIV (WLHIV) and 20% (n=135) without HIV. At enrolment, 37% (n=250) were diagnosed with at least one STI, of which 76% (n=190) were asymptomatic. STI prevalence was 40% (n=213) in WLHIV and 27% (n=37) in women without HIV (p=0.01). Baseline STI infection was associated with younger age (OR=0.95 per year, 95% CI 0.92 to 0.98), higher gestational age (adjusted OR (aOR)=1.03 per week, 95% CI 1.00 to 1.05), single relationship status (aOR=1.53, 95% CI 1.09 to 2.15) and HIV status (aOR=1.86, 95% CI 1.17 to 2.95). Of 419 participants with no STI at baseline, 21 had an incident STI during follow-up, with a mean follow-up time of 140 days. The incidence rate of STI during pregnancy and early post partum was 15 infections per 100 women-years (95% CI 9 to 23). Younger age was associated with STI incidence.ConclusionOur study shows high prevalence and incidence of STIs in pregnancy, especially in WLHIV, demonstrating the need for STI screening in ANC to prevent adverse pregnancy and birth outcomes. Most STI cases were asymptomatic and would have gone untreated with syndromic management. Aetiological STI screening is urgently needed to reduce the burden of STIs in pregnancy.
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