RESUMEN
In 2020, the WHO launched its first global strategy to accelerate the elimination of cervical cancer, outlining an ambitious set of targets for countries to achieve over the next decade. At the same time, new tools, technologies, and strategies are in the pipeline that may improve screening performance, expand the reach of prophylactic vaccines, and prevent the acquisition, persistence and progression of oncogenic HPV. Detailed mechanistic modelling can help identify the combinations of current and future strategies to combat cervical cancer. Open-source modelling tools are needed to shift the capacity for such evaluations in-country. Here, we introduce the Human papillomavirus simulator (HPVsim), a new open-source software package for creating flexible agent-based models parameterised with country-specific vital dynamics, structured sexual networks, and co-transmitting HPV genotypes. HPVsim includes a novel methodology for modelling cervical disease progression, designed to be readily adaptable to new forms of screening. The software itself is implemented in Python, has built-in tools for simulating commonly-used interventions, includes a comprehensive set of tests and documentation, and runs quickly (seconds to minutes) on a laptop. Performance is greatly enhanced by HPVsim's multiscale modelling functionality. HPVsim is open source under the MIT License and available via both the Python Package Index (via pip install) and GitHub (hpvsim.org).
Asunto(s)
Infecciones por Papillomavirus , Programas Informáticos , Neoplasias del Cuello Uterino , Humanos , Femenino , Infecciones por Papillomavirus/transmisión , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/prevención & control , Simulación por Computador , Papillomaviridae/genética , Papillomaviridae/patogenicidad , Papillomaviridae/fisiología , Biología Computacional/métodos , Modelos BiológicosRESUMEN
Less than two-thirds of US adolescents are up-to-date with HPV vaccination. While mothers engaged in preventive care are more likely to seek preventive care for their children, current studies on associations between maternal cervical cancer screening (CCS) and adolescent HPV vaccination are needed. We assessed associations between maternal preventive service utilization and adolescent HPV vaccination using electronic health record data from a healthcare system in Washington State. We included adolescents (11-17 years) and their mothers with ≥ 1 primary care visit between 2018 and 2020. Outcomes were HPV vaccine initiation and completion. The primary exposure was maternal adherence to guideline-recommended CCS. Secondary exposures were maternal breast cancer screening adherence (for mothers ≥ 52 years) and ≥ 1 wellness visit ≤ 2 years. We used Generalized Estimating Equations to estimate prevalence ratios, and explore effect modification by adolescent sex, adolescent provider characteristics, and maternal language interpreter use. Of 4121 adolescents, 66% had a CCS-adherent mother, 82% initiated HPV vaccination, and 49% completed the series. CCS adherence was associated with higher initiation (adjusted prevalence ratio (APR):1.10, 95%CI:1.06-1.13) and completion (APR:1.16, 95%CI:1.08-1.23). Associations were stronger for male vs. female adolescents, adolescents who had a primary care provider in family practice vs. pediatrics, and adolescents who had the same primary care provider as their mother vs. not. Recent maternal wellness visit was also associated with higher initiation (APR:1.04, 95%CI:1.01-1.07) and completion (APR:1.12, 95%CI:1.05-1.20). Results suggest that delivering healthcare through a family-centered approach and engaging mothers in broad preventive care could increase adolescent HPV vaccination coverage.
Asunto(s)
Detección Precoz del Cáncer , Madres , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Adolescente , Femenino , Vacunas contra Papillomavirus/administración & dosificación , Neoplasias del Cuello Uterino/prevención & control , Detección Precoz del Cáncer/estadística & datos numéricos , Madres/estadística & datos numéricos , Madres/psicología , Niño , Washingtón , Masculino , Adulto , Persona de Mediana Edad , Infecciones por Papillomavirus/prevención & control , Cooperación del Paciente/estadística & datos numéricos , Vacunación/estadística & datos numéricosRESUMEN
Internet-based surveys can be programmed and advertised in multiple languages to reach non-English-speaking individuals, but it is unclear the extent to which this enhances the diversity of participants and supports inclusion of individuals at higher risk for HIV. We sought to examine how language of survey completion (English or Spanish) was associated with sociodemographic characteristics and indicators of HIV risk and prevention among cisgender Latino sexual minority men (SMM). We analyzed national and Washington State data using the Understanding New Infections through Targeted Epidemiology (UNITE) Cohort Study (2017 and 2018) and the Washington HIV/STI Prevention Project (WHSPP) survey (2017 and 2018/2019), respectively. Latino SMM who completed online surveys in Spanish differed from those who completed surveys in English across several sociodemographic characteristics including age, education, and income. After adjusting for sociodemographic characteristics and HIV-related risk factors, Spanish language respondents in UNITE were less likely to have tested for HIV in the past year, and those in WHSPP were more likely to report a recent STI diagnosis. Findings suggest that Latino SMM who complete surveys in Spanish comprise a unique subgroup that may have a specific HIV health and risk behavior profile. Our results suggest a need for increased and tailored efforts to recruit and include Spanish-speaking Latino SMM for local and national research and public health programming.
RESUMEN: Encuestas por internet pueden ser programadas y anunciadas para alcanzar a personas que no hablan inglés, pero no queda claro si esto pueda mejorar la diversidad de los participantes de investigación y apoyar la inclusión de los individuos de alto riesgo a infección con el VIH. En este estudio examinamos la relación del idioma de completar la encuesta en línea (inglés o español) entre hombres Latinos de minorías sexuales (HLMS) cisgénero con características sociodemográficas y determinantes para el riesgo y prevención del VIH. Analizamos los datos nacionales y estatales con el estudio de cohorte de Understanding New Infections through Targeted Epidemiology (UNITE) (2017 y 2018) y El Proyecto de Washington para la Prevención del VIH/Infecciones de Transmisión Sexual (WHSPP) (2017 y 2018/2019), respectivamente. Los HLSM quienes completaron las encuestas por internet en español fueron diferentes a los que completaron las encuestas en inglés por varias características sociodemográficas incluso la edad, la educación, y el ingreso. Después de ajustar por las características sociodemográficas y los factores de riesgo asociados con el VIH, los participantes de UNITE que respondieron en español tuvieron menos probabilidad de haberse hecho la prueba de VIH en el año pasado y los que participaron en el WHSPP eran más probable que reportaran un diagnóstico de ITS. Los resultados indican que los HLSM quienes completan las encuestas en español representan un subgrupo distinto que tiene un perfil específico de comportamiento de riesgo y salud respecto al VIH. Los resultados demuestran la necesidad de mayores esfuerzos especializados para reclutar e incluir los HLSM quienes hablan español para que participen en las investigaciones en línea a nivel local y nacional y la programación de la salud pública.
Asunto(s)
Infecciones por VIH , Enfermedades de Transmisión Sexual , Estudios de Cohortes , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Hispánicos o Latinos , Homosexualidad Masculina , Humanos , Masculino , Conducta Sexual , Encuestas y Cuestionarios , Washingtón/epidemiologíaRESUMEN
BACKGROUND: Community health workers (CHWs) are essential field-based personnel and increasingly used to deliver priority interventions to achieve universal health coverage. Existing literature allude to the potential for detrimental effects of multi-tasking CHWs. This study objective was to assess the impact of integrating cervical cancer screening and prevention therapy (CCSPT) with family planning (FP) on time utilization among CHWs. METHODS: A time and motion study was conducted in 7 health facilities in Malawi. Data was collected at baseline between October-July 2019, and 12 months after CCSPT implementation between July and August 2021. CHWs trained to deliver CCSPT were continuously observed in real time while their activities were timed by independent observers. We used paired sample t-test to assess pre-post differences in average hours CHWs spent on the following key activities, before and after CCSPT implementation: clinical and preventive care; administration; FP; and non-work-related tasks. Regression models were used to ascertain impact of CCSPT on average durations CHWs spent on key activities. RESULTS: Thirty-seven (n = 37) CHWs were observed. Their mean age and years of experience were 42 and 17, respectively. Overall, CHWs were observed for 323 hours (inter quartile range: 2.8-5.5). Compared with the period before CCSPT, the proportion of hours CHWs spent on clinical and preventive care, administration and non-work-related activities were reduced by 13.7, 8.7 and 34.6%, respectively. CHWs spent 75% more time on FP services after CCSPT integration relative to the period before CCSPT. The provision of CCSPT resulted in less time that CHWs devoted towards clinical and preventive care but this reduction was not significant. Following CCPST, CHWs spent significantly few hours on non-work-related activities. CONCLUSION: Introduction of CCSPT was not very detrimental to pre-existing community services. CHWs managed their time ensuring additional efforts required for CCSPT were not at the expense of essential activities. The programming and policy implications are that multi-tasking CHWs with CCSPT will not have substantial opportunity costs.
Asunto(s)
Agentes Comunitarios de Salud , Neoplasias del Cuello Uterino , Detección Precoz del Cáncer , Femenino , Humanos , Malaui , Estudios de Tiempo y Movimiento , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & controlRESUMEN
BACKGROUND: US guidelines recommend routine human immunodeficiency virus (HIV) screening of all adults and adolescents at least once. The population-level impact of this strategy is unclear and will vary across the country. METHODS: We constructed a static linear model to estimate the optimal ages and incremental impact of adding 1-time routine HIV screening to risk-based, prenatal, symptom-based, and partner notification testing. Using surveillance data and published studies, we parameterized the model at the national level and for 2 settings representing subnational variability in the rates and distribution of infection: King County, WA and Philadelphia County, PA. Screening strategies were evaluated in terms of the percent of tests that result in new diagnoses (test positivity), cumulative person-years of undiagnosed infection, and the number of symptomatic HIV/acquired immune deficiency syndrome cases. RESULTS: Depending on the frequency of risk-based screening, routine screening test positivity was maximized at ages 30 to 34 years in the national model. The optimal age for routine screening was higher in a setting with a lower proportion of cases among men who have sex with men. Across settings, routine screening resulted in incremental reductions of 3% to 8% in years of undiagnosed infection and 3% to 11% in symptomatic cases, compared with reductions of 36% to 69% and 41% to 76% attributable to risk-based screening. CONCLUSIONS: Although routine HIV screening may contribute meaningfully to increased case detection in persons not captured by targeted testing programs in some settings, this strategy will have a limited impact on population-level outcomes. Our findings highlight the importance of a multipronged testing strategy with continued investment in risk-based screening programs.
Asunto(s)
Pruebas Diagnósticas de Rutina/métodos , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Tamizaje Masivo/métodos , Adolescente , Adulto , Trazado de Contacto , Femenino , Infecciones por VIH/epidemiología , Heterosexualidad , Homosexualidad Masculina , Humanos , Masculino , Persona de Mediana Edad , Embarazo , Conducta Sexual , Estados Unidos/epidemiología , Adulto JovenRESUMEN
The potential for human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP) to reduce the racial disparities in HIV incidence in the United States might be limited by racial gaps in PrEP care. We used a network-based mathematical model of HIV transmission for younger black and white men who have sex with men (BMSM and WMSM) in the Atlanta, Georgia, area to evaluate how race-stratified transitions through the PrEP care continuum from initiation to adherence and retention could affect HIV incidence overall and disparities in incidence between races, using current empirical estimates of BMSM continuum parameters. Relative to a no-PrEP scenario, implementing PrEP according to observed BMSM parameters was projected to yield a 23% decline in HIV incidence (hazard ratio = 0.77) among BMSM at year 10. The racial disparity in incidence in this observed scenario was 4.95 per 100 person-years at risk (PYAR), a 19% decline from the 6.08 per 100 PYAR disparity in the no-PrEP scenario. If BMSM parameters were increased to WMSM values, incidence would decline by 47% (hazard ratio = 0.53), with an associated disparity of 3.30 per 100 PYAR (a 46% decline in the disparity). PrEP could simultaneously lower HIV incidence overall and reduce racial disparities despite current gaps in PrEP care. Interventions addressing these gaps will be needed to substantially decrease disparities.
Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Negro o Afroamericano/estadística & datos numéricos , Infecciones por VIH/epidemiología , Profilaxis Pre-Exposición/estadística & datos numéricos , Población Blanca/estadística & datos numéricos , Adulto , Georgia/epidemiología , Infecciones por VIH/etnología , Infecciones por VIH/prevención & control , Disparidades en el Estado de Salud , Homosexualidad Masculina/etnología , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Incidencia , Masculino , Metaanálisis en Red , Minorías Sexuales y de Género/estadística & datos numéricos , Estados Unidos , Adulto JovenRESUMEN
BACKGROUND: Many state and local health departments now promote and support the use of HIV preexposure prophylaxis (PrEP), yet monitoring use of the intervention at the population level remains challenging. METHODS: We report the results of an online survey designed to measure PrEP use among men who have sex with men (MSM) in Washington State. Data on the proportion of men with indications for PrEP based on state guidelines and levels of awareness, interest, and use of PrEP are presented for 1080 cisgender male respondents who completed the survey between January 1 and February 28, 2017. We conducted bivariate and multivariable logistic regression to identify factors associated with current PrEP use. To examine patterns of discontinuation, we conducted Cox proportional hazards regression and fit a Kaplan-Meier curve to reported data on time on PrEP. RESULTS: Eighty percent of respondents had heard of PrEP, 19% reported current use, and 36% of men who had never used PrEP wanted to start taking it. Among MSM for whom state guidelines recommend PrEP, 31% were taking it. In multivariable analysis, current PrEP use was associated with older age, higher education, and meeting indications for PrEP use. Our data suggest that 20% of PrEP users discontinue within 12 months, and men with lower educational attainment were more likely to discontinue. CONCLUSIONS: Despite high levels of use, there is significant unmet need for PrEP in Washington. Our experience indicates that Internet surveys are feasible and informative for monitoring PrEP use in MSM.
Asunto(s)
Infecciones por VIH/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Internet , Profilaxis Pre-Exposición , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Homosexualidad Masculina , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Parejas Sexuales , Encuestas y Cuestionarios , Washingtón , Adulto JovenRESUMEN
INTRODUCTION: Women living with HIV experience heightened risk of cervical cancer, and over 50% of cases in Southern Africa are attributed to HIV co-infection. Cervical cancer interventions tailored by HIV status delivered with HIV antiretroviral therapy (ART) for treatment can decrease cancer incidence, but impact on HIV-related disparities remains understudied. METHODS: Using a dynamic model calibrated to KwaZulu-Natal, South Africa, we projected HIV prevalence, cervical cancer incidence, and proportion of cancer cases among women living with HIV between 2021-2071. Relative to the status quo of moderate intervention coverage, we modeled three additive scenarios: 1) ART scale-up only; 2) expanded human papillomavirus (HPV) vaccination, screening, and treatment; and 3) catch-up HPV vaccination and enhanced screening for women living with HIV. RESULTS: Under the status quo, HIV prevalence among women aged 15+ decreased from a median of 35% [Uncertainty Range (UR): 26-42%] in 2021 to 25% [19-34%] in 2071. The proportion of cervical cancer cases that were women living with HIV declined from 73% [63-86%] to 58% [47-74%], but incidence remained 4.3-fold [3.3-5.7] that of women without HIV. ART scale-up reduced HIV prevalence in 2071, but increased the incidence rate ratio to 5.2 [3.7-7.3]. Disparities remained after expanding cancer interventions for all women (incidence rate ratio: 4.8 [3.6-7.6]), while additional catch-up HPV vaccination and screening for women living with HIV decreased the incidence rate ratio to 2.7 [1.9-3.4] in 2071. CONCLUSIONS: Tailored cervical cancer interventions for women living with HIV can counteract rising cancer incidence incurred by extended life expectancy on ART and reduce disparate cancer burden.
Asunto(s)
Infecciones por VIH , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/prevención & control , Neoplasias del Cuello Uterino/virología , Infecciones por VIH/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/complicaciones , Adulto , Vacunas contra Papillomavirus/uso terapéutico , Vacunas contra Papillomavirus/administración & dosificación , Incidencia , Prevalencia , Adolescente , Adulto Joven , Sudáfrica/epidemiología , Persona de Mediana Edad , Detección Precoz del Cáncer , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/prevención & controlRESUMEN
Introduction: Women living with human immunodeficiency virus (WLHIV) face elevated risks of human papillomavirus (HPV) acquisition and cervical cancer (CC). Coverage of CC screening and treatment remains low in low-and-middle-income settings, reflecting resource challenges and loss to follow-up with current strategies. We estimated the health and economic impact of alternative scalable CC screening strategies in KwaZulu-Natal, South Africa, a region with high burden of CC and HIV. Methods: We parameterized a dynamic compartmental model of HPV and HIV transmission and CC natural history to KwaZulu-Natal. Over 100 years, we simulated the status quo of a multi-visit screening and treatment strategy with cytology and colposcopy triage (South African standard of care) and six single-visit comparator scenarios with varying: 1) screening strategy (HPV DNA testing alone, with genotyping, or with automated visual evaluation triage, a new high-performance technology), 2) screening frequency (once-per-lifetime for all women, or repeated every 5 years for WLHIV and twice for women without HIV), and 3) loss to follow-up for treatment. Using the Ministry of Health perspective, we estimated costs associated with HPV vaccination, screening, and pre-cancer, CC, and HIV treatment. We quantified CC cases, deaths, and disability-adjusted life-years (DALYs) averted for each scenario. We discounted costs (2022 US dollars) and outcomes at 3% annually and calculated incremental cost-effectiveness ratios (ICERs). Results: We projected 69,294 new CC cases and 43,950 CC-related deaths in the status quo scenario. HPV DNA testing achieved the greatest improvement in health outcomes, averting 9.4% of cases and 9.0% of deaths with one-time screening and 37.1% and 35.1%, respectively, with repeat screening. Compared to the cost of the status quo ($12.79 billion), repeat screening using HPV DNA genotyping had the greatest increase in costs. Repeat screening with HPV DNA testing was the most effective strategy below the willingness to pay threshold (ICER: $3,194/DALY averted). One-time screening with HPV DNA testing was also an efficient strategy (ICER: $1,398/DALY averted). Conclusions: Repeat single-visit screening with HPV DNA testing was the optimal strategy simulated. Single-visit strategies with increased frequency for WLHIV may be cost-effective in KwaZulu-Natal and similar settings with high HIV and HPV prevalence.
RESUMEN
INTRODUCTION: Cervical cancer screening (CCS) among East African immigrants (EAI) in the USA is under explored. This study aimed to investigate adherence to CCS and its correlates among EAI. METHODS: We identified 1664 EAI women (25-65 years) with ≥ 1 primary care clinic visit(s) between 2017 and 2018, using University of Washington (UW) Medicine electronic health record data. CCS adherence was defined as Pap testing within 3 years or human papillomavirus/Pap co-testing within 5 years. We used Poisson regression with robust standard errors to cross-sectionally estimate associations with correlates of adherence. Twelve-month screening uptake was also evaluated among overdue women. RESULTS: CCS adherence was 63%. Factors associated with higher adherence included older age (adjusted prevalence ratios [APRs]:1.47:95%CI:1.14-1.90, 1.38:95%CI:1.05-1.80, respectively, for ages 30-39 and 40-49 vs 25-29 years), longer duration of care at UW Medicine (APR:1.22:95%CI:1.03-1.45, comparing > 10 vs < 5 years), higher visit frequency (APR:1.23:95%CI:1.04-1.44, 1.46:95%CI:1.24-1.72, respectively, for 3-5 and ≥ 6 vs 1-2 visits), index visit in an obstetrics-gynecology clinic (APR:1.26:95%CI:1.03-1.55, vs family practice), having an assigned primary care provider (APR:1.35: 95%CI:1.02-1.79), breast cancer screening adherence (APR:1.66: 95%CI:1.27-2.17), and colorectal cancer screening adherence (APR:1.59:95%CI:1.24-2.03). Low BMI was associated with lower adherence (APR:0.50:95%CI:0.26-0.96, comparing < 18.5 kg/m2 vs 18.5-24.9 kg/m2). Among 608 (37%) overdue women, 9% were screened in the subsequent 12 months. Having commercial health insurance vs Medicare/Medicaid was associated with higher uptake (adjusted risk ratio:2.44:95%CI:1.15-5.18). CONCLUSION: CCS adherence among EAI was lower than the national average of 80%. Interventions focused on increasing healthcare access/utilization or leveraging healthcare encounters to address barriers could increase CCS in EAIs.
RESUMEN
Human papillomavirus (HPV) is the cause of almost all cases of cervical cancer, a disease that kills some 340,000 women per year. The timeline from initial infection with HPV to the onset of invasive cervical cancer spans decades, and observational studies of this process are limited to settings in which treatment of precancerous lesions was withheld or inadequate. Such studies have been critical for understanding the natural history of HPV. Modeling can shed additional insight on the natural history of HPV, especially across geographical settings with varying prevalence of factors known to affect the host-side immune response to HPV, such as HIV and tobacco use. In this study, we create models for the 30 most populous countries in Sub-Saharan Africa, each with country-specific demographic, and behavioral inputs. We found that it was not possible to fit the data if we assumed that the natural history parameters were exactly identical for all countries, even after accounting for demographic and behavioral differences, but that we could achieve a good fit with the addition of a single immunocompetence parameter for each country. Our results indicate that variation in host immune responses may play a role in explaining the differences in the burden of cervical cancer between countries, which in turn implies a greater need for more geographically diverse data collection to understand the natural history of HPV.
Asunto(s)
Infecciones por Papillomavirus , Sistema de Registros , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/epidemiología , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/inmunología , África del Sur del Sahara/epidemiología , Adulto , Papillomaviridae , Salud Global , Prevalencia , Persona de Mediana Edad , CalibraciónRESUMEN
INTRODUCTION: Antiretroviral therapy (ART) and tuberculosis preventive treatment (TPT) both prevent tuberculosis (TB) disease and deaths among people living with HIV. Differentiated care models, including community-based care, can increase the uptake of ART and TPT to prevent TB in settings with a high burden of HIV-associated TB, particularly among men. METHODS: We developed a gender-stratified dynamic model of TB and HIV transmission and disease progression among 100,000 adults ages 15-59 in KwaZulu-Natal, South Africa. We drew model parameters from a community-based ART initiation and resupply trial in sub-Saharan Africa (Delivery Optimization for Antiretroviral Therapy, DO ART) and other scientific literature. We simulated the impacts of community-based ART and TPT care programmes during 2018-2027, assuming that community-based ART and TPT care were scaled up to similar levels as in the DO ART trial (i.e. ART coverage increasing from 49% to 82% among men and from 69% to 83% among women) and sustained for 10 years. We projected the number of TB cases, deaths and disability-adjusted life years (DALYs) averted relative to standard, clinic-based care. We calculated programme costs and incremental cost-effectiveness ratios from the provider perspective. RESULTS: If community-based ART care could be implemented with similar effectiveness to the DO ART trial, increased ART coverage could reduce TB incidence by 27.0% (range 21.3%-34.1%) and TB mortality by 34.6% (range 24.8%-42.2%) after 10 years. Increasing both ART and TPT uptake through community-based ART with TPT care could reduce TB incidence by 29.7% (range 23.9%-36.0%) and TB mortality by 36.0% (range 26.9%-43.8%). Community-based ART with TPT care reduced gender disparities in TB mortality rates, with a projected 54 more deaths annually among men than women (range 11-103) after 10 years of community-based care versus 109 (range 41-182) in standard care. Over 10 years, the mean cost per DALY averted by community-based ART with TPT care was $846 USD (range $709-$1012). CONCLUSIONS: By substantially increasing coverage of ART and TPT, community-based care for people living with HIV could reduce TB incidence and mortality in settings with high burdens of HIV-associated TB and reduce TB gender disparities.
Asunto(s)
Infecciones por VIH , Tuberculosis , Humanos , Adulto , Masculino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Infecciones por VIH/epidemiología , Infecciones por VIH/complicaciones , Femenino , Tuberculosis/prevención & control , Tuberculosis/epidemiología , Tuberculosis/tratamiento farmacológico , Adulto Joven , Adolescente , Persona de Mediana Edad , Sudáfrica/epidemiología , Servicios de Salud ComunitariaRESUMEN
Introduction: Antiretroviral therapy (ART) and TB preventive treatment (TPT) both prevent tuberculosis (TB) disease and deaths among people living with HIV. Differentiated care models, including community-based care, can increase uptake of ART and TPT to prevent TB in settings with a high burden of HIV-associated TB, particularly among men. Methods: We developed a gender-stratified dynamic model of TB and HIV transmission and disease progression among 100,000 adults ages 15-59 in KwaZulu-Natal, South Africa. We drew model parameters from a community-based ART initiation and resupply trial in sub-Saharan Africa (Delivery Optimization for Antiretroviral Therapy, DO ART) and other scientific literature. We simulated the impacts of community-based ART and TPT care programs during 2018-2027, assuming that community-based ART and TPT care were scaled up to similar levels as in the DO ART trial (i.e., ART coverage increasing from 49% to 82% among men and from 69% to 83% among women) and sustained for ten years. We projected the number of TB cases, deaths, and disability-adjusted life years (DALYs) averted relative to standard, clinic-based care. We calculated program costs and incremental cost-effectiveness ratios from the provider perspective. Results: If community-based ART care could be implemented with similar effectiveness to the DO ART trial, increased ART coverage could reduce TB incidence by 27.0% (range 21.3% - 34.1%) and TB mortality by 36.0% (range 26.9% - 43.8%) after ten years. Increasing both ART and TPT uptake through community-based ART with TPT care could reduce TB incidence by 29.7% (range 23.9% - 36.0%) and TB mortality by 36.0% (range 26.9% - 43.8%). Community-based ART with TPT care reduced gender disparities in TB mortality rates by reducing TB mortality among men by a projected 39.8% (range 32.2% - 46.3%) and by 30.9% (range 25.3% - 36.5%) among women. Over ten years, the mean cost per DALY averted by community-based ART with TPT care was $846 USD (range $709 - $1,012). Conclusions: By substantially increasing coverage of ART and TPT, community-based care for people living with HIV could reduce TB incidence and mortality in settings with high burdens of HIV-associated TB and reduce TB gender disparities.
RESUMEN
Community-based delivery and monitoring of antiretroviral therapy (ART) for HIV has the potential to increase viral suppression for individual- and population-level health benefits. However, the cost-effectiveness and budget impact are needed for public health policy. We used a mathematical model of HIV transmission in KwaZulu-Natal, South Africa, to estimate population prevalence, incidence, mortality, and disability-adjusted life-years (DALYs) from 2020 to 2060 for two scenarios: 1) standard clinic-based HIV care and 2) five-yearly home testing campaigns with community ART for people not reached by clinic-based care. We parameterised model scenarios using observed community-based ART efficacy. Using a health system perspective, we evaluated incremental cost-effectiveness and net health benefits using a threshold of $750/DALY averted. In a sensitivity analysis, we varied the discount rate; time horizon; costs for clinic and community ART, hospitalisation, and testing; and the proportion of the population receiving community ART. Uncertainty ranges (URs) were estimated across 25 best-fitting parameter sets. By 2060, community ART following home testing averted 27.9% (UR: 24.3-31.5) of incident HIV infections, 27.8% (26.8-28.8) of HIV-related deaths, and 18.7% (17.9-19.7) of DALYs compared to standard of care. Adolescent girls and young women aged 15-24 years experienced the greatest reduction in incident HIV (30.7%, 27.1-34.7). In the first five years (2020-2024), community ART required an additional $44.9 million (35.8-50.1) annually, representing 14.3% (11.4-16.0) of the annual HIV budget. The cost per DALY averted was $102 (85-117) for community ART compared with standard of care. Providing six-monthly refills instead of quarterly refills further increased cost-effectiveness to $78.5 per DALY averted (62.9-92.8). Cost-effectiveness was robust to sensitivity analyses. In a high-prevalence setting, scale-up of decentralised ART dispensing and monitoring can provide large population health benefits and is cost-effective in preventing death and disability due to HIV.
RESUMEN
INTRODUCTION: In settings with high HIV prevalence, cervical cancer incidence rates are up to six-fold higher than the global average of 13.1 cases per 100,000 women-years. To inform strategies for global cervical cancer elimination, we used a dynamic transmission model to evaluate scalable screening and treatment strategies, accounting for HIV-associated cancer risks and weighing prevention gains against overtreatment. METHODS: We developed a dynamic model of HIV-HPV co-infection and disease progression, which we calibrated to KwaZulu-Natal, South Africa. Our baseline scenario reflects the current practice of HPV vaccination with a multi-visit screening and treatment strategy involving cytology and colposcopy triage. We evaluated 13 comparator scenarios with increased vaccination coverage and one-time, two-time or repeat HIV-targeted cervical cancer screening with the following single-visit strategies: HPV DNA testing, HPV genotyping, automated visual evaluation (AVE) and HPV DNA with AVE triage. In all scenarios, HIV antiretroviral therapy, condom use and voluntary male medical circumcision continue at baseline levels. We simulated cancer incidence under each scenario from 2020 to 2120 using the 25 best-fitting parameter sets. We present the median and range of model output from these simulations to account for parameter uncertainty. RESULTS: We estimate that cervical cancer incidence will decrease by 87% with the continuation of current cervical cancer and HIV prevention strategies, from an age-standardized rate per 100,000 women of 80.4 (range 58.2, 112.1) in 2020 to 10.7 (4.2, 29.9) in 2120. Scenarios scaling up vaccination and single-visit strategies resulted in near- and long-term gains. With repeat HIV-targeted screening, incidence rates were projected to be 29-34% lower in 2030 relative to the baseline scenario, and elimination (incidence <4/100,000) was achieved with HPV DNA testing in 2095 and with AVE in 2114. A strategy of HPV DNA with AVE triage optimized the tradeoff between cancer cases averted and overtreatment. CONCLUSIONS: Single-visit screening strategies could avert a substantial burden of cervical cancer and accelerate progress towards elimination in settings with a high burden of HIV. Increasing the screening frequency among women with HIV and reducing loss-to-follow-up for treatment will be key components of a successful elimination strategy.
Asunto(s)
Infecciones por VIH , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Detección Precoz del Cáncer , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Masculino , Tamizaje Masivo , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/prevención & control , Sudáfrica/epidemiología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/prevención & controlRESUMEN
BACKGROUND: Cervical cancer incidence is high in Kenya due to HIV and limited access to cancer prevention services. Human papillomavirus (HPV) has been shown to increase HIV acquisition; however, the potential impact of HPV vaccination on HIV is unknown. We modeled the health impact of HPV vaccination in the context of the HIV epidemiology in Kenya. METHODS: Using a validated compartmental transmission model of HIV and HPV set in Kenya, we evaluated five scenarios of nonavalent HPV vaccination: single-age-vaccination of 10-year-old girls at 90% coverage; multi-age-cohort (MAC) vaccination of 10-14-year-old girls at 90% coverage; MAC plus moderate-coverage (50%) catch-up vaccination of 15-24-year-old women; MAC plus high-coverage (80%) catch-up of 15-24-year-old women; and MAC plus catch-up of 15-44-year-old women at 80% coverage (HPV-FASTER). We compared cervical cancer incidence, HIV prevalence, and cumulative cervical cancer and HIV cases averted after 50 years to a baseline scenario without vaccination. In all scenarios, we assumed the UNAIDS 90-90-90 goal for HIV treatment is attained by 2030. FINDINGS: In 2021, model-estimated cervical cancer incidence is 44/100,000 and HIV prevalence among women is 6·5%. In 2070, projected cancer incidence declines to 27/100,000 and HIV prevalence reaches 0·3% without vaccination. With single-age-vaccination, cancer incidence in 2070 is reduced by 68%, averting 64,529 cumulative cancer cases. MAC vaccination reduces cancer incidence by 75%, averting 206,115 cancer cases. Moderate and high-coverage catch-up and HPV-FASTER reduce cancer incidence by 80%, 82%, and 84%, averting 254,930, 278,690, and 326,968 cancer cases, respectively. In all scenarios, HIV prevalence in 2070 is reduced by a relative 8-11%, with 15,609-34,981 HIV cases averted after 50 years. INTERPRETATION: HPV vaccination can substantially reduce cervical cancer incidence in Kenya in the next 50 years, particularly if women up to age 24 are vaccinated. HIV treatment scale-up can also alleviate cervical cancer burden. However, HPV vaccination has modest additional impact on HIV when antiretroviral therapy coverage is high. FUNDING: National Institutes of Health, Bill and Melinda Gates Foundation.
RESUMEN
Background: In 2020, the World Health Organization (WHO) launched its initiative to eliminate cervical cancer as a public health problem. To inform global efforts for countries with high HIV and cervical cancer burden, we assessed the impact of human papillomavirus (HPV) vaccination and cervical cancer screening and treatment in South Africa, on cervical cancer and the potential for achieving elimination before 2120, considering faster HPV disease progression and higher cervical cancer risk among women living with HIV(WLHIV) and HIV interventions. Methods: Three independent transmission-dynamic models simulating HIV and HPV infections and disease progression were used to predict the impact on cervical cancer incidence of three scenarios for all women: 1) girls' vaccination (9-14 years old), 2) girls' vaccination plus 1 lifetime cervical screen (at 35 years), and 3) girls' vaccination plus 2 lifetime cervical screens (at 35 and 45 years) and three enhanced scenarios for WLHIV: 4) vaccination of young WLHIV aged 15-24 years, 5) three-yearly cervical screening of WLHIV aged 15-49 years, or 6) both. Vaccination assumed 90% coverage and 100% lifetime protection with the nonavalent vaccine (against HPV-16/18/31/33/45/52/58). Cervical cancer screening assumed HPV testing with uptake increasing from 45% (2023), 70% (2030) to 90% (2045+). We also assumed that UNAIDS 90-90-90 HIV treatment and 70% male circumcision targets are reached by 2030. We examined three elimination thresholds: age-standardised cervical cancer incidence rates below 4 or 10 per 100,000 women-years, and >85% reduction in cervical cancer incidence rate. We conducted sensitivity analyses and presented the median age-standardised predictions of outcomes of the three models (minimum-maximum across models). Findings: Girls' vaccination could reduce age-standardised cervical cancer incidence from a median of 47.6 (40.9-79.2) in 2020 to 4.5 (3.2-6.3) per 100,000 women-years by 2120, averting on average â¼4% and â¼46% of age-standardised cumulative cervical cancer cases over 25 and 100 years, respectively, compared to the basecase. Adding 2 lifetime screens helped achieve elimination over the century among all women (2120 cervical cancer incidence: 3.6 (1.9-3.6) per 100,000 women-years), but not among WLHIV (10.8 (5.3-11.6)), and averted more cumulative cancer cases overall (â¼45% over 25 years and â¼61% over 100 years compared to basecase) than girls' vaccination alone. Adding three-yearly cervical screening among WLHIV (to girls' vaccination and 2 lifetime cervical screens) further reduced age-standardised cervical cancer incidence to 3.3 (1.8-3.6) per 100,000 women-years overall and to 5.2 (3.9-8.5) among WLHIV by 2120 and averted on average 12-13% additional cumulative cancer cases among all women and 21-24% among WLHIV than girls' vaccination and 2 lifetime cervical screens over 25 years or longer. Long-term vaccine protection and using the nonavalent vaccine was required for elimination. Interpretation: High HPV vaccination coverage of girls and 2 lifetime cervical screens could eliminate cervical cancer among women overall in South Africa by the end of the century and substantially decrease cases among all women and WLHIV over the short and medium term. Cervical cancer elimination in WLHIV would likely require enhanced prevention strategies for WLHIV. Screening of WLHIV remains an important strategy to reduce incidence and alleviate disparities in cervical cancer burden between women with and without HIV, despite HIV interventions scale-up. Funding: World Health Organization. National Cancer Institute, National Institutes of Health. MRC Centre for Global Infectious Disease Analysis, UK Medical Research Council. National Institute of Child Health and Human Development research. Cancer Association of South Africa. Canadian Institutes of Health Research and the Fonds de recherche du Québec - Santé research.
RESUMEN
Mathematical models of sexually transmitted disease (STI) are increasingly relied on to inform policy, practice, and resource allocation. Because STI transmission requires sexual contact between two or more people, a model's ability to represent the dynamics of sexual partnerships can influence the validity of findings. This ability is to a large extent constrained by the model type, as different modeling frameworks vary in their capability to capture patterns of sexual contact at individual, partnership, and network levels. In this paper, we classify models into three groups: compartmental, individual-based, and statistical network models. For each framework, we describe the basic model structure and discuss key aspects of sexual partnership dynamics: how and with whom partnerships are formed, partnership duration and dissolution, and temporal overlap in partnerships (concurrency). We illustrate the potential implications of accurately accounting for partnership dynamics, but these effects depend on characteristics of both the population and pathogen; the combined impact of these partnership and epidemiologic dynamics can be difficult to predict. While each of the reviewed model frameworks may be appropriate to inform certain research or policy questions, modelers and consumers of models should carefully consider the implications of sexual partnership dynamics for the questions under study.
Asunto(s)
Parejas Sexuales , Enfermedades de Transmisión Sexual , Humanos , Modelos Estadísticos , Modelos Teóricos , Conducta Sexual , Enfermedades de Transmisión Sexual/epidemiologíaRESUMEN
The World Health Organization announced an ambitious call for cervical cancer elimination worldwide. With existing prevention and treatment modalities, cervical cancer elimination is now within reach for high-income countries. Despite limited financing and capacity constraints in low-and-middle-income countries (LMICs), prevention and control efforts can be supported through integrated services and new technologies. We conducted this scoping review to outline a roadmap toward cervical cancer elimination in LMICs and highlight evidence-based interventions and research priorities to accelerate cervical cancer elimination. We reviewed and synthesized literature from 2010 to 2020 on primary and secondary cervical cancer prevention strategies. In addition, we conducted expert interviews with gynecologic and infectious disease providers, researchers, and LMIC health officials. Using these data, we developed a logic model to summarize the current state of science and identified evidence gaps and priority research questions for each prevention strategy. The logic model for cervical cancer elimination maps the needs for improved collaboration between policy makers, production and supply, healthcare systems, providers, health workers, and communities. The model articulates responsibilities for stakeholders and visualizes processes to increase access to and coverage of prevention methods. We discuss the challenges of contextual factors and highlight innovation needs. Effective prevention methods include HPV vaccination, screening using visual inspection and HPV testing, and thermocoagulation. However, vaccine coverage remains low in LMICs. New strategies, including single-dose vaccination could enhance impact. Loss to follow-up and treatment delays could be addressed by improved same-day screen-and-treat technologies. We provide a practical framework to guide cervical cancer elimination in LMICs. The scoping review highlights existing and innovative strategies, unmet needs, and collaborations required to achieve elimination across implementation contexts.