Meritxell Sabidó

Field evaluation of the performance and testing costs of a rapid point-of-care test for syphilis in a red-light district of Manaus, Brazil

Objectives: To assess the performance, usefulness and cost of a rapid treponemal antibody assay (VisiTect Syphilis) to detect syphilis in high risk populations. Methods: People who attended STI clinics in Manaus, Brazil, were screened for syphilis using the fluorescent treponemal antibody absorption (FTA-Abs) test and a non-treponemal test (Venereal Diseases Research Laboratory (VDRL)), and for HIV. Finger prick blood samples were tested with VisiTect Syphilis. The rapid test was evaluated against the reference FTA-Abs and for its usefulness in detecting active syphilis (FTA-Abs and VDRL positive). Operational performance was assessed through providers’ and patients’ interviews. An economic evaluation was conducted from the provider’s perspective. Results: 510 patients (60% men) were enrolled, of whom 13 (2.5%) were HIV-1 seropositive. Syphilis prevalence (FTA-Abs) was 18% and active syphilis prevalence was 7.5%. 11% (57/506) of samples were positive by VisiTect. The sensitivity, specificity, positive and negative predictive values of VisiTect Syphilis were 57% (95% CI 45.8 to 66.7), 99% (95% CI 97.0 to 99.6), 91% (95% CI 80.0 to 96.7) and 91% (95% CI 88.0 to 93.5), respectively. VisiTect Syphilis identified 79% (30/38) of active syphilis cases. The cost per case of syphilis was

The UALE project: decline in the incidence of HIV and sexually transmitted infections and increase in the use of condoms among sex workers in Guatemala.

16.8 for VDRL,

Comparison of users of an HIV/syphilis screening community-based mobile van and traditional voluntary counselling and testing sites in Guatemala.

33.2 for low cost and

Field performance of a rapid point-of-care diagnostic test for antenatal syphilis screening in the Amazon region, Brazil

56.3 for high cost VisiTect Syphilis; the cost per case of active syphilis was

High prevalence of human papillomavirus infection in the female population of Guatemala

21.3,

Rapid point-of-care diagnostic test for syphilis in high-risk populations, Manaus, Brazil.

57.5 and

Lessons learned from integrating simultaneous triple point-of-care screening for syphilis, hepatitis B, and HIV in prenatal services through rural outreach teams in Guatemala.

97.6, respectively. Patients identified finger prick pain and preference for venous blood collection as minor barriers to test use. Conclusion: VisiTect Syphilis had low sensitivity in field use and was less cost effective than conventional VDRL. However, rapid and correct identification of a high proportion of active syphilis cases combined with operational characteristics suggest a role in high risk populations.

HIV and sexually transmitted infections at the borderlands: situational analysis of sexual health in the Brazilian Amazon

Objectives: To assess the impact of a multilevel sexually transmitted infections (STI)/HIV prevention and treatment intervention on the incidence of STIs and HIV, the use of condoms, and HIV knowledge among sex workers (SWs). Methods: An open-enrolment cohort of 1554 SWs attending STI clinics integrated within the primary health care system of Escuintla, Guatemala. They were offered 6 monthly STI/HIV screening, condom promotion, education, and community-based interventions. We evaluated trends in condom use, HIV-related knowledge, and STI/HIV incidence using generalized estimating equations. Results: For over three and a half years, there was a significant increase in the proportion of consistent condom use from the baseline visit through the third follow-up visit (94.29%-99.11% with new clients and 90.36%-97.22% with regular clients) and in HIV-related knowledge (95.99%-97.22%). Except for syphilis, we observed a significant decline in gonorrhoea, chlamydia, trichomoniasis, and candidiasis in each follow-up visit, from 11.30 per 100 person-years, 10.71 per 100 person-years, 6.88 per 100 person-years, and 8.23 per 100 person-years in the first follow-up visit to 6.44 per 100 person-years, 6.21 per 100 person-years, 4.81 per 100 person-years, and 6.17 per 100 person-years in the third follow-up visit, for each STI, respectively. HIV global incidence was 0.41 per 100 person-years, and it significantly declined from 1.85 per 100 person-years (2005) to 0.42 per 100 person-years (2008). Conclusions: Although a longer follow-up would be needed, the results suggest that the intervention was feasible and has been shown to be effective in reducing STI and HIV incidence and in increasing condom use with clients and HIV-related knowledge.

Notification for sexually transmitted infections and HIV among sex workers in Guatemala: acceptability barriers and preferences.

Objectives The use of a mobile van (MV) for screening for HIV and other sexually transmitted infections (STIs) is effective at reaching at-risk populations. The aim of this study was to compare behaviour characteristics and HIV and syphilis prevalence between subjects tested at a MV offering voluntary counselling and testing and those tested at three STI clinics in Guatemala. Methods Over 28 months, female sex workers (FSWs), men who have sex with men/transgenders (MSM/TG), and people not reporting being a member of a risk group (NR) were offered HIV and syphilis rapid tests and interviewed about their sociodemographic and risk behaviour. Results 2874 subjects were tested (MV, 1336 (46%); clinics, 1538 (54%)). The MV screened 73% of FSWs and 73% of the MSM/TG, and detected 19% of HIV and 69% of syphilis cases. HIV prevalence was significantly higher (p<0.001) at the STI clinics than at the MV for both NR and MSM/TG groups (NR, 7% vs 1%; MSM/TG, 8% vs 1%, respectively). A significantly higher proportion of MSM/TG screened at the STI clinic reported having had a prior HIV test (MV, 21%; clinics, 41%; p<0.001), whereas more FSWs tested in the MV reported having multiple partners and using condoms during their last sexual intercourse. Conclusions The higher prevalence of HIV and syphilis at the STI clinics suggests that they successfully identified high-risk subjects. In particular, the NR group showed higher than expected HIV and syphilis prevalence. Innovative approaches such as the use of a MV helped to increase access to other hard-to-reach groups such as MSM/TG and FSWs.

Etiology of Genital Ulcer Disease in a Sexually Transmitted Infection Reference Center in Manaus, Brazilian Amazon

We evaluated an immunochromatographic point-of-care (POC) syphilis test in 712 pregnant women under field conditions in remote communities of the Amazon region (Brazil), and identified risk factors for syphilis. Women were screened by POC test using whole blood obtained by fingerprick, the fluorescent treponemal antibody absorption (FTA-Abs) test as the gold standard and the Venereal Diseases Research Laboratory (VDRL) test to determine test performance in active syphilis. Multivariate analysis was conducted to identify factors associated with syphilis infection. Among women, 2.2% had syphilis (positive FTA-Abs) and 0.8% active syphilis (FTA-Abs and VDRL positive). In all, 2.2% of samples were positive by the POC test. The sensitivity, specificity, positive and negative predictive values were 62.5% (95% confidence interval [CI]: 38.6–81.5), 99.1% (95% CI: 98.1–99.6), 62.5% (95% CI: 38.6–81.5) and 99.1% (95% CI: 98.1–99.6), respectively. The POC test identified 62.5% (10/16) of syphilis cases, 66.7% (4/6) of active syphilis cases and all high-titre syphilis cases (VDRL > 1:8). Older age was associated with syphilis infection. The rapid test performed moderately well as a screening tool for low-risk populations. This combined with on-site testing and same day treatment could expand antenatal syphilis screening programmes in distant communities characterized by difficult access to antenatal services and infrequent clinical follow-up visits.