The Bellan Lab takes a broad quantitative perspective to address applied questions in infectious disease epidemiology. Our research spans multiple pathogen systems (HIV, Ebola, anthrax, rabies) but is united by an overarching theme: the integration of mathematical and statistical models with empirical data to understand infectious disease processes and how to control them. By building simulation models of how diseases spread at the population level, we can help to interpret available data and to plan rigorous empirical studies. Our research particularly focuses on this intersection between epidemiological study design and transmission dynamics–that is, we aim to improve study design and interpretation by understanding the dynamical transmission processes underlying an epidemic and how they might bias studies.

We are firm believers in simulation for validation. Analytical approaches should always first be tested on simulated data for which the underlying truth is known. If analyses cannot recapture the truth underlying simulated data, then we should not trust results obtained by applying such approaches to data from the real world.

HIV Epidemiology

Our HIV research program aims to better understand population-wide trends of HIV transmission in the sub-Saharan African HIV epidemic. Specifically, we are interested in how HIV transmission during various stages in an individual’s relationship history (single, coupled) contribute to new HIV infections as well as to the creation of serodiscordant couples (i.e., couples with one HIV-positive and one HIV-negative partner), how to use this information to target interventions, and how to use this information to understand variation in HIV epidemic severity across sub-Saharan African (Bellan et al. 2013, Champredon et al. 2013).

We also develop rigorous quantitative frameworks for understanding how timing of antiretroviral treatment initiation and other factors affect HIV patient care outcomes, in collaboration with the Infectious Disease Institute of Kampala, Uganda (Sempa et al. 2016) and the Tanzanian Ministry of Health (Means et al. 2016).

Ebola Virus Disease and Vaccine Efficacy Trial Design

During the recent West African Ebola Epidemic, Dr. Bellan and colleagues investigated how subclinical Ebola infections might affect epidemic dynamics and control (Bellan et al. 2014) and provided planning support to the US Center for Disease Control and Prevention (CDC) for their Ebola vaccine efficacy trial in Sierra Leone (Bellan et al. 2015). We are engaged in ongoing work with a large set of international partners to develop a simulation tools for identifying optimal vaccine efficacy trial designs during catastrophic emerging epidemics, including the development of a quantitative framework for navigating tradeoffs amongst various ethical criteria.

For a full list of publications please see the Publications page.

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