Associate Professor
Department of Epidemiology, Bloomberg School of Public Health
The Johns Hopkins University
HIV/TB coinfection, diagnostic epidemiology, mathematical modeling, economic evaluation
I am an infectious disease epidemiologist and practicing general internist with cross-cutting expertise in diagnostic epidemiology, implementation science, mathematical/mechanistic modeling, and economic evaluation/cost-effectiveness analysis. My area of greatest content expertise is the epidemiology of tuberculosis (TB), including TB diagnosis/case-finding and the interplay between TB and HIV coinfection. I am also interested in the mechanistic modeling of HIV transmission in the United States, and I work closely with other members of the CFAR on agent-based and compartmental models of domestic HIV transmission. I work in diverse field sites including South Africa, Uganda, Malawi, Zambia, Pakistan, and Vietnam. I also have a defined interest in training and mentorship, specifically of junior investigators interested in transdisciplinary research that spans epidemiology, quantitative modeling methods, economic evaluation, and clinical research.
Cost-effectiveness analysis, mathematical modeling, diagnostic evaluation, quantitative implementation studies, study design, expertise in transmission dynamics and HIV/TB coinfection
1. Strategies for Treating, Observing, Managing, and Preventing Tuberculosis (STOMP TB)
STOMP TB is an in-depth evaluation of TB transmission in four urban parishes of Kampala, Uganda. The goal is to identify transmission links, quantify the proportion of TB prevalence and transmission that could have been averted through targeted interventions, and to use this data to set up interventions to impact the overall TB epidemic in Uganda.
2. Kharitode TB
This project is a cluster randomized trial of active case-finding interventions for TB across 56 health clinics in Limpopo Province, South Africa. In partnership with the Perinatal HIV Research Unit and the Setshaba Research Centre, we are comparing various case-finding strategies, including facility-based screening, household contact investigations, and incentive-based contact tracing. The overall goal is to elucidate transmission links, perform costing and implementation analyses, and develop mechanistic epidemiological models to better understand TB transmission in the context of rural-urban migration.
3. Modeling TB hotspots and transmission potential in Dhaka North and South City Corporations
In collaboration with partners through Challenge TB, we are constructing spatially explicit models of TB transmission in Dhaka, Bangladesh, and are estimating TB incidence in each ward of Dhaka over time. We will then link this to a mechanistic model of TB transmission to estimate the benefit of targeting TB interventions.
4. Models to advance the elimination of TB in California, Texas, New York, and Florida
As part of the Emory Coalition for Applied Modeling for Prevention, we have developed individual-level transmission models of TB in four states (California, Texas, New York, and Florida) that account for over half of all TB incidence in the United States each year. We are now performing cost-effectiveness and emerging interventions analyses that include novel diagnostic testing, shorter treatment regimens for latent TB infection, and vaccines.
5. Agent-based simulation of HIV and sexually transmitted infection (STI) transmission among men who have sex with men in Baltimore City
In collaboration with the Baltimore City Health Department and the CDC, we have developed an agent-based simulation model of HIV and STI transmission among men who have sex with men in Baltimore. This model has been used to quantify the added value of HIV pre-exposure prophylaxis as implemented within STI clinics in Baltimore.
