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Epidemiology Doctoral Student Profiles

Learn more about the focus of our students' research in Drexel Dornsife's PhD in Epidemiology program.

Table of Contents:

Paola Arevalo, MS

Paola Arevalo headshot

Degrees: MS in Nutrition and Foods with focus in Health Promotion and Prevention of Chronic Diseases, University of Chile; BS in Nutrition, Rafael Landivar University in Guatemala

Focus: Paola is a Graduate Research Fellow in Drexel’s Urban Health Collaborative (UHC), under the “Social determinants of cardiovascular disease risk factors over the life course” D-43 grant.

Research Interests:

  • Health determinants and inequities
  • Chronic diseases prevention
  • Food environments and policies
  • Urban health
  • Health promotion
  • Data analysis methods

Professional Experience::

  • Research assistant in the Institute of Nutrition of Central America and Panama (INCAP), leading the data analysis in projects related with the Food and Agriculture Organization (FAO), World Health Organization (WHO) and Pan-American Health Organization (PAHO)
  • Junior investigator in the project “Monitoring of sodium and trans fats in packaged products of Panama”
  • Research assistant with the University of Chile, focusing in the assessment of non-nutritive sweeteners in children and further recommendations to policy makers

Contact: paa49@drexel.edu

Mercy Atuahene, MS

Mercy Atuahene headshot

Degrees: MS in Applied Statistics, West Chester University; MS in Statistics and Operations Research, University of Orleans, France; BS in Mathematics, Kwame Nkrumah University of Science and Technology, Ghana

Research Interests:

  • Maternal and child health
  • Pharmacoepidemiology

Professional Experience:: Mercy is a Senior Principal Biostatistical Programmer at Incyte Corporation. In her seven years at Incyte, Mercy has worked with a team of statisticians and clinical programmers in drug development.

As a Biostatistical Programmer, Mercy provides clinical summaries to team members via statistical programming and summarization of clinical trial data. These summaries provide insights to team members to advance drug development in the Dermatology and Cancer Therapeutic Areas.

Mercy is proud to highlight her contributions to clinical trial data for Opzelura, a recently FDA-approved treatment for Vitiligo and Atopic Dermatitis.

Contact: mka67@drexel.edu

Luwam Gebrekristos, MPH

Degrees: MPH from Drexel University Dornsife School of Public Health; BA in Public Health Studies from Johns Hopkins University

Focus: Luwam is interested in examining the social and structural factors that drive racial and gender health inequalities. Currently, Luwam is a research fellow in the Department of Community Health and Prevention.

Research Interests:

  • Adolescent health
  • Sexual and reproductive health
  • Mental health
  • Health disparities

Publications:

Gebrekristos, L. T., Groves, A. K., McNaughton Reyes, L., Maman, S., & Moodley, D. (2020). IPV victimization in pregnancy increases postpartum STI incidence among adolescent mothers in Durban, South Africa. AIDS care, 32(sup2), 193-197.

Groves, A. K., Reyes, H. L. M., Gebrekristos, L. T., Moodley, D., & Maman, S. (2020). Examining why age-disparate relationships influence unsafe sex postpartum among South African women: relationship control and physical partner violence as explanatory mechanisms. Journal of interpersonal violence, 0886260520944531.

Purtle, J., Gebrekristos, L. T., Keene, D., Schlesinger, P., Niccolai, L., & Blankenship, K. M. (2020). Quantifying the Restrictiveness of Local Housing Authority Policies Toward People With Criminal Justice Histories: United States, 2009–2018. American Journal of Public Health, 110(S1), S137-S144.

Groves, A. K., Gebrekristos, L. T., Reyes, L. M., Moodley, D., & Maman, S. (2020). Describing Relationship Characteristics and Postpartum HIV Risk Among Adolescent, Young Adult, and Adult Women in South Africa. Journal of Adolescent Health.

Mark Hernandez, MPH

Mark Hernandez headshot

Degrees: MPH in Monitoring and Evaluation from Boston University; BS in Electrical Engineering from University of Illinois at Urbana-Champaign

Focus: Mark is currently working with Dr. Gina Lovasi to examine how gentrification impacts neighborhood social environment and health inequities.

Research Interests:

  • Neighborhood change and gentrification
  • Residential segregation
  • Social epidemiology
  • Population mental health
  • Cardiovascular disease

Professional Experience: Prior to joining the doctoral program, Mark worked as a researcher at MIT for eight years. In that time, his research spanned multiple areas across health technology and public health informatics. Mark previously led a collaboration between MIT, Boston University, and the State of Maine’s Office of Behavioral Health to develop data analytics and decision support tools for Maine’s mental health crisis system.

Publications:

  • Hernandez MA, Modi S, Mittal K, Dwivedi P, Nguyen QC, Cesare NL, Nsoesie EO. Diet during the COVID-19 pandemic: An analysis of Twitter data. Patterns (N Y). 2022 Aug 12;3(8):100547.
  • Abdalla SM, Hernandez M, Fazaludeen Koya S, Rosenberg SB, Robbins G, Magana L, Nsoesie EO, Sabin L, Galea S. What matters for health? Public views from eight countries. BMJ Glob Health. 2022 Jun;7(6):e008858.

Contact: mah557@drexel.edu

Diana Higuera-Mendieta, MD, ScM

Diana Higuera-Mendieta headshot

Degrees: MD from Universidad de los Andes, Bogota Colombia; ScM in Epidemiology from Johns Hopkins Bloomberg School of Public Health

Focus: Exploring the mechanisms that produce health disparities in urban settings and assess how cities can implement strategies to reduce such fundamental causes.

Research Interests:

  • Urban health
  • Social determinants of health
  • Health disparities

Professional Experience: After completing her medical training in Bogotá, Colombia, she worked exploring the eco-bio-social determinants of Aedes aegypti productivity in urban settings, which led her to pursue a Master's in Epidemiology at Johns Hopkins University.

Soon after graduating, she enrolled in the SALURBAL team in her country, where she collaborated in the harmonization efforts to have a data platform that integrates health outcomes with physical and social environment data in 11 Latin American countries. She has participated in different interdisciplinary efforts to evaluate urban interventions and their effect on the health of urban populations. During the COVID-19 pandemic, she got involved in mathematical modeling efforts that informed selective lockdowns in Bogotá, dose spacing of mRNA vaccines, and antiviral purchases for Colombia. Besides her work involving epidemiologic techniques, she is a lecturer on epidemiological methods at Universidad de los Andes in Bogotá, Colombia.

Publications:

  • Higuera-Mendieta D, González S, Chrisinger B, Rodriguez Castañeda N, Rosas LG, Banchoff A, García J, Mejía-Cancelado C, Triana C, King A & Sarmiento OL (2023). Our Voice in the Ciclovía: exercising recreation and health rights through Citizen Science, Cities & Health, 7:1, 122-136, DOI: https://doi.org/10.1080/23748834.2022.2119815
  • Higuera-Mendieta D, Uriza PA, Cabrales S, Medaglia AL, Guzman LA, Sarmiento OL. Is the built-environment at origin, on route, and at destination associated with bicycle commuting? A gender-informed approach. Journal of Transport Geography.2021; 94:103120. doi: https://doi.org/10.1016/j.jtrangeo.2021.103120
  • Ortigoza AF, Tapia Granados JA, Miranda JJ, Higuera-Mendieta D, et al (2021) Characterizing variability and predictors of infant mortality in urban settings: findings from 286 Latin American cities. J Epidemiol Community Health 2021;75:264-270. doi: https://doi.org/10.1136/jech-2020-215137
  • Sarmiento OL, Higuera-Mendieta D, Wilches-Mogollon MA, Guzman LA, Rodríguez DA, Morales R, Méndez D, Bedoya C, et al. Urban Transformations and Health: Methods for TrUST—a Natural Experiment Evaluating the Impacts of a Mass Transit Cable Car in Bogotá, Colombia. Front. Public Health. 2020.8:64. doi: https://doi.org/10.3389/fpubh.2020.00064
  • Higuera-Mendieta D, Cortes S, Quintero J, Gonzalez C. KAP surveys and dengue control in Colombia: Disentangling the effect of sociodemographic factors using multiple correspondence analysis. PLoS Negl Trop Dis. 2016 Sep 28;10(9):e0005016. doi: https://doi.org/10.1371/journal.pntd.0005016
  • García-Betancourt T, Higuera-Mendieta D, González-Uribe C, Cortés S, Quintero J. Understanding Water Storage Practices of Urban Residents of an Endemic Dengue Area in Colombia: Perceptions, Rationale and Socio-Demographic Characteristics. LaDeau SL, ed. PLoS ONE. 2015;10(6):e0129054. doi: https://doi.org/10.1371/journal.pone.0129054
  • Fuentes-Vallejo M, Higuera-Mendieta D, García-Betancourt T, Alcalá-Espinosa L, García-Sánchez D, Munévar-Cagigas D et al. Territorial analysis of Aedes aegypti distribution in two Colombian cities: a chorematic and ecosystem approach. Cad. Saúde Pública. 2015. Mar;31( 3 ): 517-530 10.1590/0102-311x00057214
  • See all publications on Google Scholar

Contact: drh89@drexel.edu

Justin Jones, MPH

Justin Jones headshot

Degrees: MPH, Epidemiology of Microbial Diseases & Global Health, Yale School of Public Health; BS, International Health & African American Studies, Georgetown University

Focus: Justin is working with Dr. Seth Welles, professor in the Epidemiology and Biostatistics department. His bachelor’s thesis focused on HIV/TB co-occurring infections in Dar es Salaam, Tanzania. His MPH thesis focused on chronic disease manifestations in persons living with HIV in KwaZulu-Natal, South Africa. He also completed and published an independent research project on malaria resistance gene emergence in sub-Saharan Africa. Before joining Drexel he worked as the research coordinator for two large NIDA funded projects at Texas Christian University focused on HIV and opioid overdoses in parolees in Texas, Illinois and New Mexico.

Research Interests:

  • HIV
  • Tuberculosis (TB)
  • Malaria

Professional Experience: Justin worked in emergency medicine research and as a EMT before obtaining his MPH from Yale.

Apollo Kivumbi, MBchB, MPH, MMed

Apollo Kivumbi headshot

Degrees: MBchB from Makerere University; MPH from Johns Hopkins University; MMed (Psychiatry) from Makerere University

Focus: Apollo's focus is on neurodevelopmental disorders.

Research Interests:

  • Autism spectrum disorders

Professional Experience: I worked as a research coordinator and later as a principal investigator on a multisite NIH funded study as well as an R21.I have also worked as a psychiatrist in a child and adolescent mental health clinic in Mulago Hospital in Uganda.

Publications: View Apollo's publications on PubMed

Contact: ak4337@drexel.edu

Edwin McCulley, MS

Edwin McCulley headshot

Pronouns: he/him/his

Degrees: MS in Epidemiology with Biostatistics minor from Drexel University Dornsife School of Public Health; SAS Certified Base Programming Specialist, Syracuse University; BS in Health Science from Drexel University College of Nursing and Health Professions

Focus: Edwin’s doctoral dissertation focuses on the intersection of healthcare accessibility, cardiovascular disease, and COVID-19 outcomes.

Research Interests:

  • Epidemiologic research methods
  • Urban health
  • Spatial epidemiology

Professional Experience: Edwin’s public health journey began as an enlisted US Navy Hospital Corps member where he gained experience managing various preventive medicine programs and projects. Prior to his doctoral studies, Edwin received a BS in Health Science and a MS in Epidemiology, at Drexel University, where he worked as a Research Coordinator in collaboration with health department representatives from 30 large US cities to harmonize COVID-19 data. Currently, Edwin serves as a doctoral research fellow and conducts research focused on the impact of the COVID-19 pandemic and COVID-19 outcomes, especially among vulnerable populations.

Publications:

  • Hanson D, Samendinger S, McCulley EM. Multidisciplinary understanding of modifiable physical disability risk factors for health professionals: A scoping review protocol. PLOS ONE 2024.
  • Xu G, Zhang S, McCulley EM, Wu R, Li X, Jiao L. Evolving urban allometric scaling law of the COVID-19 epidemic in the United Kingdom. Journal of Urban Management 2024.
  • Boise S, Jogi S, McCulley EM, Crossa A, Etheredge A, Lovasi G. Concepts, Characterizations, and Cautions: A Guide and Glossary for Planning Food Environment Measurement in Public Health. The Open Public Health Journal 2023.
  • Spoer B, McCulley EM, Lampe T, Pei Yang H, Chen A, Ofrane RH, Rollins H, Thorpe LE, Bilal U, Gourevitch MN. Validation of a Neighborhood-level COVID Local Risk Index in 47 Large U.S. Cities. Health and Place 2022.
  • Bilal U, Mullachery PH, Schnake-Mahl AS, Rollins H, McCulley EM, Kolker J, Barber S, Diez Roux AV. Heterogeneity in Spatial Inequities in COVID-19 Vaccination across 16 Large US Cities. American Journal of Epidemiology 2022.
  • McCulley EM, Mullachery PH, Ortigoza AF, Rodriguez DA, Diez Roux AV, Bilal U. Urban Scaling of Health Outcomes: a scoping review. Journal of Urban Health 2022.
  • Bilal U, McCulley EM, Li R, Rollins H, Schnake-Mahl A, Mullachery PH, Vaidya V, Koh C, Dureja K, Sharaf A, Furukawa A, Juliano C, Barber S, Kolker J, Diez Roux AV. Tracking COVID-19 Inequities across jurisdictions represented in the Big Cities Health Coalition: The COVID-19 Health Inequities in BCHC Cities Dashboard. American Journal of Public Health 2022.
  • McCulley EM, Mullachery P, Rodriguez D, Diez-Roux AV, Bilal U. Urban Scaling of Health Outcomes: a protocol for a scoping review. BMJ Open 2019; 9 (11), e031176

Links to Research:

  • McCulley, EM, Lovasi, G., Crossa, A., Etheredge, A., Boise, S., Bayer, J. [Dashboard] January 2024. Food Environment Electronic Database Directory (Version 7). Drexel University: Dornsife School of Public Health. www.foodenvironmentdirectory.com.
  • Barber S, Bilal U, Diez Roux A, Furukawa A, Koh C, Kolker J, Li R, McCulley EM, Rollins H, Schnake-Mahl A, Sharaf A, Vaidya, V. Tracking Inequities in COVID-19 Related Outcomes in Select Cities. [Dashboard] January 2020. Urban Health Collaborative. Retrieved from www.covid-inequities.info

Academic Service: PHDSAG, Delta Omega National Honorary Society

Notable Awards: Drexel Common Good Award (2023), TA Excellence Award (2022), Mentor Recognition Award (2021)

Contact: Linktree

Francesca Mucciaccio, MPH

Francesca Mucciaccio headshot

Degrees: MPH in Health Policy from Emory University; BA in Linguistics (focus on linguistic anthropology) from Reed College

Focus: Francesca is a Doctoral Fellow at the Urban Health Collaborative.

Research Interests:

  • Measurement approaches to address racial, ethnic, and spatial disparities in chronic disease
  • The effects of neighborhood-level factors and built environment on the development of chronic disease in urban contexts

Professional Experience: Previously, she was a public health analyst at the Centers for Disease Control and Prevention, working on federal policy and strategy development and science translation. Through the years, she worked in multiple areas, including chronic disease, emergency response, global health, and sickle cell disease.

Contact: fam47@drexel.edu

Shreya Patel, MPH

Shreya Patel headshot

Degrees: MPH in Epidemiology from George Washington University; BS in Public Health from University of South Carolina

Focus: Research Fellow

Research Interests:

  • Urban health
  • Environmental exposures
  • Spatial analysis
  • Health disparities

Professional Experience: Prior to coming to Drexel, Shreya worked as a research analyst at the National Cancer Institute, where she worked on several research projects examining the relationship between physical activity and cancer incidence and mortality. Prior to this, Shreya was a global health surveillance fellow at CDC, where she helped implement and monitor national bio-behavioral surveys among PEPFAR countries.

Publications:

  • Matthews CE, Carlson S, Saint-Maurice PF, Fulton J, Patel S, Loftfield E, Sampson JN, Keadle SK, Berrigan D. Changes in Physical Activity and Sedentary Time in United States Adults in Response to COVID19: Fall 2019-2020. PloS One. 2022 Sep 9;17(9):e0273919
  • Saint-Maurice PF, Berrigan D, Whitfield GP, Watson KB, Patel S, Loftfield E, JN Sampson, Fulton J, Matthews CE. Amount, Type, and Timing of Moderate-to-Vigorous Physical Activity Among US Adults. J Phys Act Health. 2021 Aug 1;18(S1):S114-S122.
  • Matthews CE, Carlson S, Saint-Maurice PF, Patel S, Salerno EA, Loftfield E Troiano RP, Fulton J, Sampson JN, Tribby C, Keadle S, Berrigan D. Sedentary Behavior in United States Adults: Fall 2019. Medicine and Science in Sports and Exercise. 2021 Jul 23.
  • Nguyen LT, Patel S, Nguyen NT, Gia HH, Raymond HF, Abdul-Quader AS. Population Size Estimation of Female Sex Workers in Hai Phong, Vietnam: Use of Three Source Capture–Recapture Method. Journal of Epidemiology and Global Health. 2021 Mar;11(2):194-9.
  • Matthews CE, Troiano RP, Salerno EA, Berrigan D, Patel S, Shiroma EJ, Saint-Maurice PF. Exploration of Confounding Due to Poor Health in an Accelerometer-Mortality Study. Medicine and Science in Sports and Exercise. 2020 May 27.

Contact: sp3784@drexel.edu

Ana Lucía Peralta, MD MSCI

Ana LucĂ­a Peralta

Degrees: MD from Universidad de San Carlos de Guatemala; MPH in Epidemiology from Universidad Rafael Landívar; MSCI from Tulane University

Research Interests:

  • Chronic disease prevention
  • Implementation science
  • Social determinants of health
  • Health disparities

Professional Experience:: Ana Lucía worked as research assistant at Tulane University School of Public Health for the CATCH Study, where she supported the development of a team-based care strategy to improve hypertension control in Colombia and Jamaica. She had previously worked at the Research Center for the Prevention of Chronic Diseases (CIIPEC) where she coordinated the field implementation of an effectiveness-implementation trial for Hypertension control in Guatemala.

Contact: alp395@drexel.edu

Nicole Rafalko, MPH, CPH, CIC

Nicole Rafalko

Preferred Pronouns: she/her 

Degrees: MPH in Infectious Diseases and Microbiology from University of Pittsburgh with a certificate in global health; BS in Biobehavioral Health from Penn State University

Focus: Nicole’s dissertation research is titled, "The clinical epidemiology of sepsis: balancing sepsis program and antibiotic stewardship initiatives."

Research Interests:

  • Clinical epidemiology
  • Hospital acquired infections
  • Antimicrobial stewardship
  • Real world research
  • Epidemiological methods

Professional Experience:: Before joining Drexel, Nicole worked at the Montgomery County (PA) Office of Public Health, most recently as an Epidemiology Research Associate. In this role, she led surveillance initiatives, managed communicable disease outbreaks, and helped design and conduct epidemiological studies.

Publications:

  • Rafalko, N., Webster, J. L., Jacob, G., Kutzler, M. A., & Goldstein, N. D. (2024). Generalizability of predictive models for Clostridioides difficile infection, severity and recurrence at an urban safety-net hospital. Journal of Hospital Infection, 146, 10-20.
  • Webster, J. L., Rafalko, N., Thorpe, L. E., Duncan, D. T., Gracely, E. J., & Goldstein, N. D. (2023). Alignment of Ending the HIV Epidemic Priority Jurisdictions With Availability of HIV Service Organizations: An Ecological Study. AIDS Education and Prevention, 35(4), 320-331.

Contact: nr644@drexel.edu

Katherine Roshak-Durst, MPH

Katherine Roshak headshot

Degrees: MPH in Epidemiology from Drexel University Dornsife School of Public Health; BS in Biology with a minor in Spanish from Ursinus College

Research Interests:

  • Cancer epidemiology
  • Genetic epidemiology
  • Epidemiologic methods
  • Autoimmune diseases

Professional Experience: Before returning to Dornsife for her PhD in Epidemiology, Katherine worked in the pharmaceutical industry, specializing in clinical trial operations for oncology investigational medicines. Katherine works as an Oncology Senior Local Trial Manager at the Janssen Pharmaceutical Companies of Johnson & Johnson and is pursuing her PhD in Epidemiology part-time.

Contact: kmr396@drexel.edu

Victoria Ryan, MSPH

 Victoria Ryan headshot

Degrees: MSPH from the Johns Hopkins Bloomberg School of Public Health; BA in English from the College of William and Mary

Focus: Victoria is working as a doctoral fellow on Dr. Stephen Lankenau’s grant, “Medical Marijuana, Emerging Adults, and Community: Connecting Health and Policy” and her advisor is Dr. Ayden Scheim.

Research Interests:

  • Infectious diseases, including HIV
  • Mental health and substance use disorders
  • Harm reduction

Professional Experience: Most recently, Victoria worked as a data manager and analyst on a randomized, controlled trial examining screening and treatment for toddlers with autism, and on a study examining the association of community-level factors with the risk of developing type 2 diabetes. Prior to this, she served as a strategic information advisor for the US Agency for International Development for HIV/AIDS programs.

Contact: vdr28@drexel.edu

Heather Santos, MPH

Heather Santos headshot

Degrees: MPH in Epidemiology from Drexel University Dornsife School of Public Health; BS in Physics from Penn State University

Focus: Heather is working with Dr. Ayden Scheim, focusing on transgender health in Canada.

Research Interests:

  • Mental health
  • Psychiatric epidemiology
  • Adolescent health
  • LGBT health

Professional Experience: Prior to beginning her MPH, Heather worked for two years as a research technician at Penn State, simulating global measles burden based on varying financial investments and vaccination scenarios, for WHO and Gavi.

Contact: hds44@drexel.edu

Anna Simpson, MPH

Anna Simpson headshot

Pronouns: they/them

Degrees: MPH with an emphasis in Epidemiology from the University of Louisville; BS in Psychology from the University of Louisville

Focus: Anna is working with Dr. Stephanie Hernandez to understand social and structural factors that contribute to health disparities and access to healthcare among sexual and gender minorities (SGM) using an intersectional lens.

Research Interests:

  • LGBTQ+ health
  • Social determinants of health
  • Mental health
  • Social epidemiology
  • Health disparities

Professional Experience: Anna worked as a research assistant at the University of Louisville School of Public Health and Information Sciences where they conducted community-engaged research on health-related decision-making among Asian-American communities. Anna also assisted with the HEAL study, a part of the Green Heart Louisville Project at the Christina Lee Brown Envirome Institute.

Contact: ats348@drexel.edu

Chioma Uzoigwe, MPH

Chioma Uzoigwe headshot

Degrees: MPH with a concentration in Epidemiology from the University of Medicine and Dentistry of New Jersey; BA in Psychology from Stanford University

Focus: Chioma is a Senior Director in Real World Evidence at Novo Nordisk, where she has worked for the past 12 years. She has supported multiple therapeutic areas during her career at Novo Nordisk, including growth hormone, hemophilia and diabetes. Chioma currently leads a team of researchers who support observational studies in MASH, cardiovascular disease and Alzheimer’s disease.

Research Interests:

  • Outcomes research
  • Pharmacoepidemiology

Professional Experience: Chioma previously worked as a research analyst for The Robert Wood Johnson Foundation and Mathematica Policy Research, where she conducted work in public health disparities and health policy.

Contact: cu53@drexel.edu

Rachel Vecchione, MPH

Rachel Vecchione headshot

Degrees: MPH from Thomas Jefferson University; BS/BA in Biochemistry and Molecular Biology and French from the University of Georgia

Focus: Rachel currently works at the A.J. Drexel Autism Institute where she focuses on the impact of maternal diet on ASD outcomes.

Research Interests:

  • Impact of environmental factors on autism spectrum disorder

Contact: rv422@drexel.edu