Preferences for Conditional Economic Incentives to Improve Pre-exposure Prophylaxis Adherence: A Discrete Choice Experiment Among Male Sex Workers in Mexico.

Pre-exposure prophylaxis (PrEP) is highly effective in preventing HIV but requires sustained adherence. Conditional economic incentives (CEIs) can improve medication-taking behaviors, yet preferences for programs that employ CEIs to increase PrEP use among male sex workers (MSWs) have not been investigated. We conducted a discrete choice experiment in Mexico City to elicit stated preferences for a CEI-based PrEP adherence program among MSWs. Respondents expressed their preferences for different program characteristics: incentive amount; incentive format; incentive type; and adherence-verification method. We used a random utility logit model to estimate the relative importance of each attribute and estimated willingness-to-pay. MSWs preferred a higher, fixed incentive, with PrEP adherence measured via hair sampling. MSWs were willing to forego up to 21% of their potential maximum CEI amount to ensure receipt of a fixed payment. MSWs are highly willing to accept a CEI-based intervention for PrEP adherence, if offered along with fixed payments.

RESUMEN: La profilaxis previa a la exposición (PrEP) es muy eficaz para prevenir el VIH, pero requiere una adherencia sostenida. Los incentivos económicos condicionales (IEC) pueden mejorar los comportamientos de toma de medicamentos, sin embargo, no se han investigado las preferencias por los programas que emplean IEC para aumentar el uso de PrEP entre los trabajadores sexuales masculinos (TSM). Realizamos un experimento de elección discreta con TSM en la Ciudad de México para obtener preferencias declaradas para un programa de adherencia a la PrEP basado en IEC. Los participantes expresaron sus preferencias en cuanto a diferentes características: monto del incentivo; formato del incentivo; tipo de incentivo; y método de verificación de la adherencia. Utilizamos un modelo logit de utilidad aleatoria para estimar la importancia relativa de cada atributo y la disposición a pagar estimada (DAP). Los TSM prefirieron un incentivo fijo más alto, con la adherencia a la PrEP medida a través de muestras de cabello. Los TSM estaban dispuestos a renunciar hasta el 21% de su monto máximo potencial de IEC para garantizar la recepción de un pago fijo. Los TSM están muy dispuestos a aceptar una intervención basada en IEC para la adherencia a la PrEP, si se ofrece junto con pagos fijos.

Syphilis infection markers among HIV positive individuals in the Mexico City HIV/AIDS Program / Marcadores de infección por sífilis de individuos VIH positivos en el Programa de VIH/SIDA de la Ciudad de México

Abstract: Objective: The aim of this study is to evaluate the prevalence of T. pallidum infection markers in HIV-positive individuals receiving highly active antiretroviral therapy (ART) in the Mexico City HIV/AIDS Program, as well as predictive characteristics. Materials and methods: The reverse serologic algorithm method was used for the T. pallidum diagnosis, and applied to 2 383 HIV-positive individuals. Sociodemographic characteristics, sexual practices, previous syphilis diagnosis, and length of antiretroviral treatment, were evaluated. Variables significantly associated with syphilis markers were analyzed using a logistic regression model. Results: Prevalence of "active or resolved" and "probable active" infection markers were 44.2 and 28.8%, respectively. Predictive factors were: Clínica Especializada Condesa Iztapalapa (CECI), previous syphilis diagnosis, men in who have sex with men (MSM), and receptive sex practices. Conclusions: The prevalence of T. pallidum infection markers was the highest ever reported in Mexico, and was related to specific sexual practices as well as previous syphilis diagnosis, elements which require preventive measures in the Mexico City HIV/AIDS Program.

Resumen: Objetivo: Evaluar las prevalencias de marcadores de infección por T. pallidum en personas que viven con VIH y reciben tratamiento antirretroviral en el Programa de VIH/SIDA de la Ciudad de México, así como sus características asociadas. Material y métodos: Se siguió el método del algoritmo reverso para el diagnóstico de T. pallidum aplicado a 2 383 individuos VIH positivos, quienes contestaron un cuestionario sobre características sociodemográficas, prácticas sexuales, diagnóstico previo de sífilis y tiempo de tratamiento antirretroviral. Las variables significativamente asociadas con los marcadores de sífilis se analizaron mediante un modelo de regresión logística. Resultados: Las prevalencias de marcadores de infección "activa o resuelta" y "probablemente activa" fueron 44.2 y 28.8%, respectivamente. Las características asociadas con los marcadores fueron Clínica Especializada Condesa Iztapalapa (CECI), diagnóstico previo de infección por sífilis, hombres que tienen sexo con hombres (HSH) y prácticas sexuales receptivas. Conclusiones: Las prevalencias de marcadores de infección por T. pallidum fueron altas y estuvieron relacionadas con prácticas sexuales específicas y con el diagnóstico previo de sífilis, características que requieren medidas preventivas dentro del programa.

Syphilis Infection Markers Among HIV Positive Individuals In The Mexico City HIV/AIDS Program.

OBJECTIVE: The aim of this study is to evaluate the prevalence of T. pallidum infection markers in HIV-positive individuals receiving highly active antiretroviral therapy (ART) in the Mexico City HIV/AIDS Program, as well as predictive characteristics. METHODS: The reverse serologic algorithm method was used for the T. pallidum diagnosis, and applied to 2,383 HIV-positive individuals. Socio-demographic characteristics, sexual practices, previous syphilis diagnosis, and length of antiretroviral treatment, were evaluated. Variables significantly associated with syphilis markers were analyzed using a logistic regression model. RESULTS: Prevalence of "active or resolved" and "probable active" infection markers were 44.2% and 28.8%, respectively. Predictive factors were: Clinic Specialized Condesa Iztapalapa (CECI), previous syphilis diagnosis, MSM, and receptive sex practices. CONCLUSIONS: The prevalence of T. pallidum infection markers was the highest ever reported in Mexico, and was related to specific sexual practices as well as previous syphilis diagnosis, elements which require preventive measures in the Mexico City HIV/AIDS Program.

Uptake of the HPV vaccine among people with and without HIV, cisgender and transgender women and men who have sex with men and with women at two sexual health clinics in Mexico City.

Our aim was to better understand Human Papillomavirus (HPV) vaccine acceptance among Mexican adults including people with and without HIV, cisgender men who have sex with men (MSM) or with women (MSW), cisgender and transgender women. A computer-assisted, self-administered questionnaire was completed by healthcare users and participants recruited through community organizations, and the first dose of the quadrivalent HPV vaccine was offered at no cost at a large sexual health clinic in Mexico City, from May to December 2018. Socio-demographic characteristics and factors associated with HPV vaccine acceptance were analyzed using logistic regression.The sample of 1915 participants included 1341 cisgender men (70.9%, 1247 MSM and 94 MSW), 396 (20.7%) cisgender women and 178 (9.3%) transwomen; 615 people (32.1%) were HIV positive. Uptake of the HPV vaccine was higher in men and transwomen (91.5% and 87%, respectively) than among cisgender women (81.8%; p < .001). Cisgender women (OR 0.43, 95%CI 0.30-0.61, p < .05) were less likely to accept HPV vaccination than men. Married/partnered people were less likely to accept HPV vaccination compared to those who were single (OR 0.70, 95%CI 0.51-0.97). People living with HIV were not significantly more likely to accept HPV vaccination (OR 1.7; 95%CI 0.86-1.61).HPV vaccine acceptance was high among adult Mexican study participants; it may be higher than among other Mexican adults given most of these individuals are engaged in care. Modifications will be needed in national and international recommendations on HPV vaccination in adults if healthcare personnel are to recommend the vaccine to the population groups studied.

[Identification of meeting places of sexual partners in 2 cities of the Southern Mexican borders, using the PLACE method]. / Identificación de sitios de encuentro de parejas sexuales en dos ciudades de la frontera sur de México, mediante el método PLACE.

OBJECTIVE: To identify the meeting sites of new sexual partners in two Southern border cities in Mexico. MATERIAL AND METHODS: A descriptive epidemiologic study was carried out in May 2001, by surveying key informants in two border cities. Each reported site was visited to interview a resident subject. Subjects socializing in a subsample of sites were also interviewed. RESULTS: The key informants of the community reported 134 meeting sites in Chetumal and 111 in Ciudad Hidalgo. Both sites had scarce HIV/AIDS prevention activities. Characteristics were obtained for 89 sites in Chetumal and 42 in Ciudad Hidalgo. Almost 21% of interviewees reportedly met a new sexual partner in these sites in the past four weeks. CONCLUSIONS: Preventive actions are needed in meeting sites of new sexual partners. This method may provide information to plan for future interventions. The English version of this paper is available too at:http://www.insp.mx/salud/index.html.

Identificación de sitios de encuentro de parejas sexuales en dos ciudades de la frontera sur de México, mediante el método PLACE / Identification of meeting sites of new sexual partners in two Southern border cities in Mexico using the PLACE method

OBJETIVO: Identificar sitios de encuentro de nuevas parejas sexuales en dos ciudades de la frontera sur de México. MATERIAL Y MÉTODOS: En un estudio epidemiológico descriptivo se encuestó, en mayo de 2001, a informantes clave de la comunidad en dos ciudades fronterizas del sur de México para identificar sitios de encuentro de nuevas parejas. Se visitó cada sitio reportado y se encuestó a una persona del lugar. De una submuestra de sitios, se encuestó a personas que socializaban en los mismos. RESULTADOS: Los informantes clave de la comunidad reportaron 134 sitios en Chetumal y 111 en Ciudad Hidalgo. Se obtuvo información de las características de 89 sitios en Chetumal y 42 en Ciudad Hidalgo, ambos con escasas actividades preventivas del VIH/SIDA. Cerca de 21 por ciento de usuarios encuestados reportaron haber conocido una nueva pareja en los sitios en las últimas cuatro semanas. CONCLUSIONES: Son necesarias acciones de prevención en los sitios de encuentro de nuevas parejas sexuales. Este método puede proveer información para planificar futuras intervenciones.