Core Faculty

Andrew Azman

Andrew is a Research Associate in the Department of Epidemiology. His work focuses on understanding the spatio-temporal dynamics of enteric pathogens, like cholera, and strategies to best control outbreaks. In addition, Andrew works on methods for estimating intervention effects, particularly vaccine, with observational study designs. Andrew earned his PhD in epidemiology and MHS in biostatistics from Johns Hopkins Bloomberg School of Public Health. Before coming to Hopkins, Andrew received his B.S. and M.S. in Environmental Engineering from University of Colorado and practiced as an engineer.

M. Kate Grabowski

Mary Kate Grabowski is an Assistant Professor in the Department of Pathology at Johns Hopkins University. She also works as an epidemiologist with the Rakai Health Sciences Program (RHSP) in Rakai District, Uganda. Her primary research interests include the epidemiology and transmission dynamics of sexually transmitted viral infections, local geography and structure of sexual contact networks, and viral phylodynamics. Kate’s research focuses on the transmission, prevention, and control of sexually transmitted viral infections in East Africa. She has spent nearly a decade living/working in African settings where she has been involved in various infectious disease epidemiological and laboratory-based studies. Kate is also currently a member of the Bill and Melinda Gates funded PANGEA-HIV consortium through RHSP. PANGEA-HIV aims to generate 20,000 whole genome HIV sequences to understand HIV transmission dynamics in Africa.

Emily Gurley

Emily is an Associate Scientist in the Department of Epidemiology and leads multi-disciplinary studies on the transmission and prevention of emerging and vaccine preventable diseases, such as Nipah virus, hepatitis E virus, and arboviruses. She has worked in Bangladesh for more than a decade and her interests include improving the communication and collaboration between field epidemiologists and infectious disease modelers and development of novel surveillance strategies. Her research adopts a One Health approach to the study and prevention of infectious disease, taking into account the ecological context in which human disease occurs. Emily is the Co-Director for the Child Health and Mortality Prevention Surveillance (CHAMPS) site in Bangladesh, aiming to determine the etiology of and prevent child deaths. She also works closely with the US Centers for Disease Control and Prevention’s Global Disease Detection program.

Justin Lessler

Justin Lessler is an Associate Professor in the department of Epidemiology researching the dynamics and control of infectious disease, with particular interest in influenza, measles, cholera and dengue. Justin works on the development and application of statistics, dynamic models and novel study designs to better understand and control infectious disease. In particular, he is interested in creating synergies between infection control practice, data collection and infectious disease dynamics.

Amy Wesolowski

Amy is an Assistant Professor in the department of Epidemiology. She is interested in understanding how human behavior can impact infectious disease dynamics. She uses a range of statistical and dynamical models to better understand disease transmission and control. She also works to use novel data sources to describe human populations. She primarily works in Africa and Asia supporting both field and modeling studies. She completed her PhD in Engineering and Public Policy from Carnegie Mellon University in 2014.

Affiliated Faculty

Derek Cummings

Derek is an infectious disease epidemiologist engaged in theoretical and field studies of disease transmission. The goal of his research is to understand the temporal and spatial dynamics of the spread of infectious diseaess in order to inform interventions to control their spread. He is specifically interested in the dynamics of dengue, influenza, measles, and chikungunya. He currently leads field studies of influenza in the US and China, and dengue and chikungunya in Thailand and India. 

Frank Curriero

Dr. Curriero is an Associate Professor in the Department of Epidemiology with joint appointments in the Departments of Biostatistics and Environmental Health Sciences at the Johns Hopkins Bloomberg School of Public Health.  Dr. Curriero’s research focus is on the development and application of spatial and spatial-temporal statistical methods in the public health sciences.  Much of his current work involves translating methods of spatial science involving spatial data, GIS and spatial statistics for building research capacity in wide ranging health research applications.  Dr. Curriero is director of the newly forming Johns Hopkins Spatial Science for Public Health Center as well as the online Master of Applied Science in Spatial Analysis for Public Health program.

David Dowdy

David Dowdy is an Associate Professor of Epidemiology at the Johns Hopkins School of Public Health, with joint appointments in International Health and General Internal Medicine (School of Medicine). His primary research interest lies in merging epidemiological data on implementation, economic evaluation, and mechanistic modeling to understand the dynamics of tuberculosis (TB) - particularly the impact of interventions to improve diagnosis and case finding. He collaborates with field teams in an array of countries including South Africa, Uganda, Zambia, Malawi, India, and Vietnam; he is also a practicing physician in urban East Baltimore and is wrapped around the little finger of his 12-year-old daughter Chesapeake.

Oliver Laeyendecker

Oliver is a laboratory scientist and infectious disease epidemiologist engaged in studies of HIV, HCV and HSV-2 both domestically and internationally. Primary areas of interest include the development of methods for estimating incidence from cross-sectional surveys, the impact of HIV subtype on disease progression, and the development of serologic and molecular tools to investigate questions related to infectious disease epidemiology. Oliver has worked in infectious disease laboratories since 1990 and holds a PhD in epidemiology, a MS in biotechnology and an MBA all from Johns Hopkins University. He is employed by the NIAID as a Staff Scientist, where he manages the International HIV & STD laboratory of Dr. Thomas C. Quinn. He also has an appointment as an Assistant Professor of Medicine in the Division of Infectious Diseases in the Department of Medicine of Johns Hopkins University and holds a joint appointment as an Assistant Professor in Epidemiology at the Johns Hopkins Bloomberg School of Public Health. He works closely with the Rakai Health Sciences Program and the HIV Preventions Trials Network.

William Moss

William Moss is a Professor in the Departments of Epidemiology, International Health and Molecular Microbiology and Immunology at the Johns Hopkins Bloomberg School of Public Health and Head of Epidemiology at the International Vaccine Access Center. He is a pediatrician with subspecialty training in infectious diseases, and has worked in Ethiopia, Kenya, South Africa, Zambia, Zimbabwe and India among other countries. His broad research interests are the epidemiology and control of childhood infections in resource-poor countries. The specific focus of his current research is in understanding the impact of the HIV epidemic on measles control and eradication, the epidemiology and control of malaria in southern Africa, and the care and treatment of HIV-infected children in rural Zambia.

Heather McKay

Heather McKay is a Research Associate  in the Department of Epidemiology at the Johns Hopkins Bloomberg School of Health. Her research experience has focused on the role of circulating biomarkers of inflammation and immune activation in HIV disease progression, including the role of pre-infection and early levels of inflammatory response on subsequent viral setpoint levels and inflammatory dynamics early after infection on long-term non-progression of HIV. Her recent research interests also include the interaction between HIV infection and the dynamics of cholera transmission, the immunogenicity of oral cholera vaccine among HIV-infected populations, and the characterization of global cholera epidemiology.  She has also been involved with classroom instruction of both introductory and advanced epidemiology courses at Johns Hopkins for over 6 years and the revision of the 5th edition of the best-selling introductory textbook, Epidemiology (Dr. Leon Gordis).  Prior to her career at Johns Hopkins, Heather spent 15 years working in the philanthropic/grantmaking sector in New York with responsibilities in program development, management, and evaluation on issues associated with ethnic conflict prevention and resolution, strengthening higher education and research in Africa, international peace and security, and support for independent scholarship. She received her BA degree in Russian History from Columbia University and her PhD in epidemiology from the Johns Hopkins Bloomberg School of Public Health.

Isabel Rodríguez-Barraquer

Isabel is an Assistant Professor in the Division of HIV, ID and Global Medicine at University of California, San Francisco. She is interested in applying novel epidemiological and statistical methods to understand the dynamics of infectious diseases. While she is interested in infectious diseases generally, most of her experience is related to vector-borne diseases such as dengue, malaria, and Zika.  Isabel completed her medical training in Colombia. She joined the ID dynamics group in 2008 and completed a PhD in epidemiology and an MHS in Biostatistics at the Johns Hopkins Bloomberg School of Public Health in 2012.

Henrik Salje

Henrik is a researcher in the mathematical modelling of infectious diseases unit at the Pasteur Institut in Paris and an Adjunct Assistant Professor in the department of epidemiology at the Johns Hopkins Bloomberg School of Public Health. His interests lie in the spatio-temporal dispersal dynamics of infectious diseases, particularly arboviruses. He works on both empirical data collection and methodological development with research projects based in Southeast Asia.




Postdoctoral fellows

John Giles

Lindsay Keegan

Lindsay is a postdoctoral fellow in the department of Epidemiology at the Johns Hopkins Bloomberg School of Public Health. Her research interests include applying mathematical and statistical techniques to basic and applied questions on the ecology and evolution of infectious diseases. Currently she is working on using statistical and mathematical techniques to understand the spread of dengue in Thailand. Lindsay completed her PhD in Biology at McMaster University focusing on modeling the effects of clinical immunity to malaria on disease spread and control and on calculating the reproductive number in a finite population of susceptible hosts. Lindsay has a Bachelors of Science in both Zoology and in Mathematics from the University of Florida (2010).

Elizabeth C. Lee

Elizabeth is a postdoctoral fellow in the Department of Epidemiology. She is interested in characterizing the spatiotemporal dynamics of infectious diseases and improving surveillance system design through the use of novel data sources and statistical modeling. Her research in the ID Dynamics group focuses on mapping the global disease burden of cholera and understanding the effect of measurement biases on epidemiological inference. Elizabeth completed her PhD in Global Infectious Diseases at Georgetown University in 2017 and her dissertation investigated the ability for medical claims to enhance influenza surveillance design.

Shaun Truelove

Shaun is a PhD candidate in infectious disease epidemiology. His current work includes measles supplemental vaccination modeling and influenza epidemiology. Prior to coming to JHSPH, he worked as an epidemiologist with the CDC’s Global Disease Detection program in Cairo, Egypt, where he worked to establish and develop respiratory disease surveillance programs throughout the Middle East. He has a BS in Biology and an MPH from the University of Wisconsin.

Amy Winter

Amy is a postdoctoral fellow in the Department of Epidemiology. She is interested in characterizing and leveraging the complex interaction between human demography and infectious disease dynamics for disease control.  Her research in the ID Dynamics group focuses on exploring strategies for measles and rubella control and elimination using modeling and serological data. Amy completed her PhD in Demography at Princeton University (2016) and MPH at Emory University (2011).

Current Students

Qifang Bi

Qifang is a PhD student in the infectious disease dynamics group. She received her MHS in Epidemiology from JHSPH in 2014 and B.S.E in biomedical engineering from Duke University in 2012. While at JHSPH, Qifang spent a summer in Bangladesh implementing the WASH Benefits Saliva Study. She is interested in studying spatio-temporal dynamics of disease transmission and the implications on control measures, and her works have focused on Cholera and Dengue. 

Lelia Chaisson

Lelia is a PhD student in infectious disease epidemiology. Her research interests include TB diagnosis, prevention, and control, and HIV/TB co-infection. Her doctoral research focuses on evaluating the impact of universal antiretroviral therapy on patient outcomes and the community burden of HIV and HIV-related comorbidities in Rio de Janeiro, Brazil. Prior to JHSPH, Lelia worked as an epidemiologist at UCSF studying the implementation of TB diagnostics in Vietnam and Uganda. Lelia has a BA in Public Health from Johns Hopkins University and an MSc in Epidemiology from the London School of Hygiene and Tropical Medicine.

Katherine Goodman

Katherine (Katie) is a PhD candidate in infectious disease epidemiology.  Her research interests include strategies for reducing healthcare-acquired infections, Gram-negative antimicrobial resistance in inpatient settings, and the development of evidence-based healthcare epidemiology and antimicrobial stewardship policies. Her doctoral research focuses on piloting rectal screening in ICU patients for a class of highly resistant bacteria, carbapenem-resistant Enterobacteriaceae (CRE), in order to dissect transmissibility heterogeneity within the bacterial class and to develop targeted screening algorithms to identify patients at high risk of asymptomatic CRE carriage.  Prior to JHSPH, she practiced FDA law in Washington, D.C., including work on drug shortages policy development and legislation, Good Manufacturing Practices (GMP) enforcement, and antibiotics in livestock regulations.  She received a post-graduate diploma in public health from the University of Auckland in New Zealand in 2013, received her JD from Columbia Law School in 2010, and holds a BA in philosophy from Dartmouth College.

Forrest Jones

Forrest began his PhD in Infectious Disease Epidemiology in 2017. Prior to JHSPH, he was an ASPPH/CDC Allan Rosenfield Global Epidemiology Fellow stationed at the CDC in Dar es Salaam, Tanzania. He received his MPH in Epidemiology of Microbial Diseases from Yale School of Public Health in 2015 and BS in Chemical Biology from UC Berkeley in 2013. He is passionate about the combined use of mathematical models and field studies to inform public health interventions.


Laura Bowles

Laura is a research assistant in the Department of Epidemiology at the Johns Hopkins Bloomberg School of Public Health.  She received her B.S. in public health sciences from the University of Massachusetts Amherst in 2016.

Keya Joshi

Keya Joshi is an epidemiologist whose research interests include the development and application of novel statistical and epidemiologic methods to model the spread of infectious diseases. Her recent work focuses on developing statistical models to inform Zika control policies in the Americas, as well as characterizing the Ebola outbreak in Liberia. She completed her MHS in infectious disease epidemiology in 2017 from JHSPH.

Joshua Kaminsky

Joshua Kaminsky is a programmer for the Department of Epidemiology at Johns Hopkins University.  His background is in mathematical data analysis, machine learning, and high performance computing.  Now he works on modeling cholera and dengue, and maintains a server for the group.

Friends, Former Students, etc.

Ben Althouse

Ben left Hopkins and became Omidyar postdoctoral fellow at the Santa Fe Institute working on mathematical models of the spread of disease in heterogenous environments. He has also developed models of the spread of arboviruses (dengue, yellow fever, chikungunya, zika, rift valley fever) in primate populations in Senegal as well as developed novel methods of predicting incidence of infectious diseases using search query data. He is currently working at the Institute for Disease Modeling in Seattle. He recieved a PhD in epidemiology in 2013 and an ScM in biostatistics in 2010 from the Johns Hopkins School of Public Health. Ben received a BS in mathematics and a BS in biochemistry from the University of Washington in 2008.

Sudarat Chadsuthi

Sudarat's research is about biophysics and stochastic modeling.  She is working on mathematical model of chikungunya, influenza, and leptospirosis. She is also interested the temporal and spatial dynamics to understand and interventions of their spread. She received an MSc degree in Physics from Physics Department, Mahidol University, Bangkok, Thailand, in 2007.

Hannah Clapham

Hannah joined the ID Dynamics group as a postdoctoral fellow in November 2013. She worked on developing and using mathematical and statistical models to further understand the dynamics of dengue transmission. This included work on the differences between serotypes, the infection to case ratio and the interaction between cross-protection and enhancement. She was interested in how this understanding can be increased by using combinations of multiple data types. Hannah completed a PhD at Imperial College, London, focused on within host modelling of dengue infection. This work aimed to understand the processes driving infection dynamics in both primary and secondary infections. Extensions to this work considered the inclusion of a realistic representation of virus dynamics in models of dengue transmission, with application to assessing the impact of Wolbachia infected mosquitoes. Hannah has a BA in Mathematics from the University of Oxford (2007) and an MSc in Epidemiology from Imperial College (2009). After Hopkins, She joined the Oxford University Clinical Research Unit (OUCRU) in Ho Chi Minh city, Vietnam as a postdoctoral researcher.

Ken Cline

Ken is a software developer who worked with the Hopkins Infectious Disease Dynamics Group from 2011 to 2015. He has a background designing and building agent-based models to simulate phenomena such as epidemics, liver tissue, cartel behavior and small-unit military operations. Before coming to Hopkins, he worked for various consulting and internet-software companies. He is interested in the study of complex systems using a spectrum of modeling approaches and the development of tools tointegrate and validate these methodologies. 

Byran Dai

Byran worked with the Infectious Disease Dynamics group on the Fluscape project. His research interest was in influenza transmission and healthcare-associated infections (HAI) dynamics. While at JHSPH, Byran served as a PHASE intern at the Maryland Department of Health, where he advised on HAI reporting requirements for the state. Byran graduated from Harvard University in 2011 with a BA in History & Science and a minor in Global Health & Health Policy, and graduated from JHSPH in 2014 with an MS in Epidemiology. He currently resides in New York City and works as a data scientist at Quartet Health.

Matthew Graham

Matt joined the ID Dynamics group as a research assistant in July 2014, and worked as a postdoctoral fellow from January 2015. He worked on measles prediction and the use of open measles data to determine control strategies. Matt completed a PhD at the University of Warwick, UK, focused on the impact of heterogeneity in human mixing on epidemics in 2015. Matt received an MMath in Mathematics from the University of Oxford (2008) and an MSc in Complexity Science from University of Warwick (2010). He now works at Oxford University Clinical Research Unit (OUCRU) in Ho Chi Minh City, Vietnam as a postdoctoral researcher.

Marisa Hast

Marisa completed her PhD in infectious disease epidemiology in 2018. Her work focuses on malaria and vector dynamics, intervention evaluation, and the contribution of human movement patterns to malaria transmission in southern Africa. Prior to coming to JHSPH, she worked at the CDC's Center for Global Health and Emory University on topics such as cholera, HIV, refugee health, and child protection in the US and abroad. 

Yanjie Huang

Yanjie obtained her master's degree in infectious disease epidemiology. She has a Bachelor of Medicine (2012) and Bachelor of Arts in Economics (2012) from Peking University. 

Jessica Ladd

Jessica Ladd is a former PhD student in infectious disease epidemiology at JHSPH. She received an MPH from Johns Hopkins in 2011 and a BA is Public Policy/Human Sexuality from Pomona College in 2008. She is the founder and CEO of Sexual Health Innovations.

Rachel Lee

Rachel obtained her master degree in the Department of International Health concentrating in Global Disease Epidemiology and Control. She worked as a graduate research assistant with the Infectious Disease Dynamics group to conduct a systematic literature review on the incubation periods for causes of viral gastroenteritis. Rachel used this research to complete her master’s thesis, which evaluated the recommendations made in The Control of Communicable Diseases Manual, a widely used resource in international public health, for clinically differentiating causes of acute gastroenteritis in the field. After receiving her masters, Rachel left Hopkins to pursue an MD at Baylor Medical College. 

Alison (Su-Hsun) Liu

Alison earned her MPH degree in 2008 and PhD degree in epidemiology in 2012 from the Johns Hopkins School of Public Health. In her doctoral thesis, she has described the temporal variability of HPV DNA and determining how menstrual phases affected the variable detection of HPV in a natural history study by applying event history analysis and time series analysis methods, respectively. After graduation, Alison has shifted her research interests towards the natural history of and host determinants for Staphylococcus aureus colonization in at-risk populations. She is also interested in determining how the intricate interplay between host hormonal status and abdominal adiposity affects the host’s risk for infection or infection outcomes. Alison received her medical degree in 2000 from National Taiwan University.

Kaitlin Rainwater Lovett

Kaitlin worked with the Infectious Disease Dynamics group to perform systematic reviews, acquire data and implement laboratory testing for projects surrounding immunity to dengue and influenza viruses. As a post-doctoral researcher in infectious disease epidemiology, Kaitlin developed human antigenic cartography to inform epidemiological measures of dengue virus infection and performed a systematic review of influenza interventions in long-term care facilities. Kaitlin left for a position at the Applied Physics Lab.

C. Jessica Metcalf

Luis Mier-y-Teran

Luis Mier-y-Teran did his undergraduate studies at UNAM, in Mexico city and then obtained a PhD in Physics at Northwestern University in 2010 working with professors, Mary Silber and Vassily Hatzimanikatis. His thesis research was on the mathematical modeling of protein synthesis from a dynamical systems perspective. His current interests lie in mathematical epidemiology. He worked with the ID Dynamics group on population models of dengue and other diseases.

Sean Moore

Sean was a postdoctoral fellow in the Department of Epidemiology at Johns Hopkins University from 2013-2017. His research interests include the ecology and epidemiology of water-borne infectious diseases. His primary research focus is the epidemiology of cholera in Africa. He is currently modeling cholera vaccination strategies and developing statistical modeling techniques to map the spatial and spatiotemporal burden of cholera throughout Africa. He has also studied the dynamics and ecology of other diseases including plague, Ebola, MERS, chikungunya, and Lyme disease. Sean has a PhD in Zoology from Oregon State University and was previously a Climate and Health Posdoctoral Fellow with the National Center for Atmospheric Research (NCAR) and the Centers for Disease Control and Prevention (CDC).

Eva Noble

Eva graduated from the University of Pennsylvania in 2010 with BA in Cognitive Science. She worked in the department of epidemiology at the Johns Hopkins School of Public Health on the SMART project with Derek Cummings, managed this site, and coordinated ID Dynamics activities from 2011-2013. She left Hopkins to pursue her MPH at Columbia University.

Rebecca Pierce

Talia Quandelacy

Talia completed her PhD in infectious disease epidemiology at the Johns Hopkins Bloomberg School of Public Health. Her interests include understanding seasonal forcing mechanisms of childhood respiratory infections, influenza dynamics and control strategies, and the evolution and animal-host interactions of zoonotic diseases. 

Nick Reich

Nick is a biostatistician whose research focuses on statistical inference in communicable disease settings. He is currently a Research Assistant Professor in the Division of Biostatistics and Epidemiology at the University of Massachusetts, Amherst. After earning his PhD in Biostatistics at Johns Hopkins, he completed a post-doc in the Hopkins Infectious Disease Dynamics group. He also has a BA in English Literature from Carleton College. Nick's primary research interests are in developing models for complex and dynamic disease systems, developing statistical methods that can draw accurate inferences from disease surveillance data, and optimizing design and analysis strategies for cluster-randomized studies. At UMass, he teaches "Introduction to Statistical Computing and Data Visualization" using R and is the author of several R packages.

Steven Riley

Steven is a professor of Infectious Disease Dynamics in Imperial College London. He studies the transmission of human pathogens. He conducts field studies, analyses data and uses mathematical models to look at scientific questions that are relevant to public health: how does our pattern of social contacts affect the transmission of respiratory infections? How much more severe is one strain of influenza than another? How far does influenza penetrate into rural areas after it sweeps through cities?

Kathryn Risher

Kathryn (Katie) completed her PhD in infectious disease epidemiology at the Johns Hopkins Bloomberg School of Public Health in 2017. Katie's research interests include HIV transmission and sexual network dynamics. Her dissertation includes the simulation of sexual networks consistent with survey data in South Africa, and simulating transmission of HIV on these consistent networks to assess network effects on HIV interventions. Her previous work has included a range of HIV-related topics focused in Southern Africa and the United States.

Kerry Shannon

Kerry is an MD/DrPH student in international Health. Her research interests relate to cholera, malaria and humanitarian relief. She is currently working on projects related to cholera in refugee camps and the DRC and a malaria mapping epidemiology project in the Hill Tracts of Bangladesh. Kerry has a B.A. in Chemistry and International Studies from Kenyon College (2004) and an MPH from Johns Hopkins (2007). Before coming to school she received a Fulbright grant to research the implications of large dam projects on communities in northeast Thailand. She later worked at a clinic on the Thai-Burma border with Burmese populations seeking healthcare, where her research related to barriers to access to healthcare and human rights violations among Burmese populations.

David Smith

David is interested in the ecology, epidemiology, and economics of infectious diseases. His primary focus is on malaria, though he has also worked on influenza, MRSA, cholera, rabies, dengue, and even some infectious diseases of plants. Basic research questions include the spatial dynamics of pathogen transmission, the measurement of transmission, the evolution of resistance, and the bioeconomics (i.e. the interplay of economic and biological factors) for infectious diseases. He also has an interest in translating knowledge into policy. He is a part of RAPIDD (Research and Policy for Infectious Disease Dynamics), the Malaria Atlas Project, and the Malaria Elimination Group. 

Saki Takahashi

Saki received her ScM in infectious disease epidemiology from JHSPH in 2013, and is currently pursuing her PhD at Princeton University. She is interested in the modeling and analysis of infectious disease dynamics and their control measures, and completed her Masters thesis with Dr. Justin Lessler on the spatial distribution of measles immunization uptake in Eastern Africa. Previously, she worked as a research assistant at the Center for Communicable Disease Dynamics at the Harvard School of Public Health, where she studied the temporal dynamics of seasonal influenza strains. Saki received her BA in Applied Mathematics from Harvard College in 2011.

Jungen Yi

Jungen was a research assistant in the department of epidemiology at the Johns Hopkins School of Public Health. She managed this website and coordinated activities for the ID Dynamics group. She received her BS in Environmental Geoscience from Boston College in 2011. She left Hopkins to pursue her MPH degree at Columbia University Mailman School of Public Health.

Carla Zelaya

Carla is an infectious disease epidemiologist focusing on behavioral and social challenges of disease prevention. At Hopkins, her research largely focused on barriers to HIV prevention and care in marginalized populations in Sub-Saharan Africa, Thailand, Vietnam and Russia, and cholera prevention. Carla left Hopkins to pursue a career as an epidemiologist at the CDC.