Mapping TB incidence across districts in Uganda to inform health program activities.

BACKGROUND: Identifying spatial variation in TB burden can help national TB programs effectively allocate resources to reach and treat all people with TB. However, data limitations pose challenges for subnational TB burden estimation. METHODS: We developed a small-area modeling approach using geo-positioned prevalence survey data, case notifications, and geospatial covariates to simultaneously estimate spatial variation in TB incidence and case notification completeness across districts in Uganda from 2016-2019. TB incidence was estimated using 1) cluster-level data from the national 2014-2015 TB prevalence survey transformed to incidence, and 2) case notifications adjusted for geospatial covariates of health system access. The case notification completeness surface was fit jointly using observed case notifications and estimated incidence. RESULTS: Estimated pulmonary TB incidence among adults varied >10-fold across Ugandan districts in 2019. Case detection increased nationwide from 2016 to 2019, and the number of districts with case detection rates >70% quadrupled. District-level estimates of TB incidence were five times more precise than a model using TB prevalence survey data alone. CONCLUSION: A joint spatial modeling approach provides useful insights for TB program operation, outlining areas where TB incidence estimates are highest and health programs should concentrate their efforts. This approach can be applied in many countries with high TB burden.

CONTEXTE: L'identification des variations spatiales de la charge de morbidité de la TB peut aider les programmes nationaux de lutte contre la TB à allouer efficacement les ressources pour atteindre et traiter toutes les personnes atteintes de TB. Cependant, les limites des données posent des problèmes pour l'estimation de la charge de morbidité infranationale. MÉTHODES: Nous avons développé une approche de modélisation à petite échelle en utilisant des données d'enquête de prévalence géolocalisées, des notifications de cas et des covariables géospatiales pour estimer simultanément la variation spatiale de l'incidence de la TB et l'exhaustivité de la notification des cas dans les districts de l'Ouganda de 2016 à 2019. L'incidence de la TB a été estimée à l'aide 1) des données au niveau des grappes de l'enquête nationale sur la prévalence de la TB de 2014­2015, transformées en incidence, et 2) des notifications de cas ajustées pour tenir compte des covariables géospatiales de l'accès au système de santé. La surface de complétude des notifications de cas a été ajustée conjointement à l'aide des notifications de cas observés et de l'incidence estimée. RÉSULTATS: L'incidence estimée de la TB pulmonaire chez les adultes a été multipliée par >10 dans les districts ougandais en 2019. La détection des cas a augmenté à l'échelle nationale entre 2016 et 2019, et le nombre de districts avec des taux de détection des cas >70% a quadruplé. Les estimations de l'incidence de la TB au niveau des districts étaient cinq fois plus précises qu'un modèle utilisant uniquement les données de l'enquête sur la prévalence de la TB. CONCLUSION: Une approche conjointe de modélisation spatiale fournit des informations utiles pour le fonctionnement des programmes de lutte contre la TB, en décrivant les domaines où les estimations de l'incidence de la TB sont les plus élevées et où les programmes de santé devraient concentrer leurs efforts. Cette approche peut être appliquée dans de nombreux pays où la charge de morbidité de la TB est élevée.

Seroepidemiology as basis for design of a human papillomavirus vaccination program.

We have performed a serological survey of HPV type 16-antibody prevalence by age and sex in Sweden and used it as a basis for modelling the optimal vaccination strategies in this population. Samples of 3,317 subjects were tested for HPV16-specific antibodies. The observed age-specific seroprevalences along with sexual behaviour data were used to infer parameter values for a mathematical model representing Sweden and the preventive effect of possible strategies estimated. By the year 2055, vaccination of females starting at age 12 in 2008 was most efficient, estimated to prevent 5.8 million cumulative HPV16 infections. Catch-up programs had a strong additional preventive effect. Vaccination also targeting males increased protective effect by about 4%, but had lower preventive effect per vaccination given. Addition of an HPV serosurvey to existing models and data has enabled us to estimate effect of different vaccination strategies, optimized to the HPV epidemiology in our population.

Strategies for the introduction of human papillomavirus vaccination: modelling the optimum age- and sex-specific pattern of vaccination in Finland.

Phase III trials have demonstrated the efficacy of human papillomavirus (HPV) vaccines in preventing transient and persistent high-risk (hr) HPV infection and precancerous lesions. A mathematical model of HPV type 16 infection and progression to cervical cancer, parameterised to represent the infection in Finland, was used to explore the optimal age at vaccination and pattern of vaccine introduction. In the long term, the annual proportion of cervical cancer cases prevented is much higher when early adolescents are targeted. Vaccinating against hr HPV generates greater long-term benefits if vaccine is delivered before the age at first sexual intercourse. However, vaccinating 12 year olds delays the predicted decrease in cervical cancer, compared to vaccinating older adolescents or young adults. Vaccinating males as well as females has more impact on the proportion of cases prevented when vaccinating at younger ages. Implementing catch-up vaccination at the start of a vaccination programme would increase the speed with which a decrease in HPV and cervical cancer incidence is observed.

The potential role of suppressive therapy for sex partners in the prevention of neonatal herpes: a health economic analysis.

BACKGROUND: The development of suppressive therapy and type specific tests for herpes infections allow for screening to reduce the risk of neonatal herpes. OBJECTIVES: To assess the potential effectiveness, cost effectiveness, and benefit of suppressive therapy among herpes simplex virus serodiscordant sex partners during pregnancy. METHODS: Decision and economic analyses are used to compare the incidence and costs of neonatal herpes in California (2000) for three interventions: (1) no management; (2) current guidelines (caesarean delivery for women with lesions); (3) screening for women at risk and use of suppressive treatment in sex partners. RESULTS: Screening and suppressive therapy are the most effective interventions, while current guidelines have limited effectiveness, but the latter provide the most cost effective results. CONCLUSIONS: While current guidelines are cost saving, they forgo a potential 82% decrease in neonatal herpes incidence that would be possible with screening and suppressive therapy if society were willing to pay the necessary US$363 000 per case prevented. To evaluate HSV screening and drug therapy completely, clinical trials and an economic assessment of infant mortality "value" to society are required.