Infectious Disease Epidemiologist

Bio
Griffin is T32 Postdoctoral Fellow in HIV Epidemiology and Prevention at the Johns Hopkins Bloomberg School of Public Health. He is an expert in geospatial methods, which he combines with techniques from molecular and social epidemiology to understand disease transmission in high-burden settings and populations. His postdoctoral work focuses on people who inject drugs, sex workers and their clients, and mobile populations in Uganda, India, and the United States. His graduate work focused on acute HIV phylogeography and malaria vaccine efficacy heterogeneity in Africa. Griffin developed a short course in Applied Spatial Epidemiology, which he has taught six times in Malawi, Ghana, and South Africa.

Education
PhD, Epidemiology, UNC Gillings School of Global Public Health
MS, Biostatistics, UNC Gillings School of Global Public Health

Other Interests
Science fiction, backpacking, hiking, yoga, pickup sports.

Incident HIV Across Space and Networks

HIV Transmission in a Declining African Epidemic
Preprint. 2026 April 30. LINK
Bell GJ, Grabowski MK, Mpagazi J, ..., Serwadda D, Chang LW, Ssekubugu R.Geospatial and Phylogenetic Clustering of Acute and Recent HIV Infections in Lilongwe, Malawi
PLOS Global Public Health. 2025 Nov 5. LINK
Bell GJ, Powers KA, Ratmann O, ..., Cohen MS, Hoffman IF, Miller WC.
Media: Speaking of Medicine and HealthUpdated Risk Score Algorithms for Acute HIV Infection Detection at a Sexually Transmitted Infections Clinic in Lilongwe, Malawi
Journal of Acquired Immune Deficiency Syndrome (JAIDS). 2024 Dec 15. LINK.
Bell GJ, Chen JS, Maierhofer CN, ..., Hoffman IF, Miller WC, Powers KA.

Structural and Historical Drivers of Disease Burden

Race, Place, and HIV: The Legacies of Apartheid and Racist Policy in South Africa
Social Science and Medicine. 2022 Mar 1. LINK.
Bell GJ, Ncayiyana J, Sholomon A, Goel V, Khangelani Z, Emch M.
Media: The GuardianCOVID-19 Testing in North Carolina: Racial, Ethnic, and Geographic Disparities
Health and Place. 2021 Apr 19. LINK.
Brandt K, Goel V, Keeler C, Bell GJ, ..., Fleischauer A, Emch M, Boyce R.Considering Alternate Pathways of Drinking-Water Contamination: Evidence of Risk Substitution from Arsenic Mitigation Programs in Rural Bangladesh.
International Journal of Environmental Research and Public Health. 2020 Jul 26. LINK.
Goel V, Bell GJ, Sridhar S, ..., Shelus V, Sobsey M, Emch M.

Malaria Vaccine Efficacy Heterogeneity

Ensuring the Public Health Impact of Malaria Vaccination in High-Transmission Settings
American Journal of Tropical Medicine & Hygiene. 2026 January 15. LINK.
Bell GJ, Emch ME, Moormann AM, Bailey JA.Background Malaria Incidence and Parasitemia during the Three-Dose RTS,S/AS01 Vaccination Series do not Reduce Magnitude of Antibody Response nor Efficacy Against the First Case of Malaria
BMC Infectious Diseases. 2023 October 23. LINK.
Bell GJ, Gyaase S, Goel V, ..., Agnandji ST, Juliano JJ, Bailey JA.Malaria Transmission Intensity Likely Modifies RTS,S/AS01 Efficacy Due to a Rebound Effect in Ghana, Malawi, and Gabon
The Journal of Infectious Diseases. 2022 July 28. LINK.
Bell GJ, Goel V, Essone P, ..., Bailey JA, Asante KP, Emch M.
Media: This Week in ParasitismImpacts of Ecology, Parasite Antigenic Variation, and Human Genetics on RTS,S/AS01e Malaria Vaccine Efficacy
Current Epidemiology Reports. 2021 July 30. LINK.
Bell GJ, Agnandji ST, Asante KP, Ghansah A, Kamthunzi P, Emch M, Bailey JA.Environmental Modifiers of RTS,S Malaria Vaccine Efficacy in Lilongwe, Malawi
BMC Public Health. 2020 Jun 12. LINK.
Bell GJ, Loop MS, Mvalo T, ..., Bailey JA, Emch M, Hoffman I.Case Reduction and Cost-Effectiveness of the RTS,S/AS01 Malaria Vaccine Alongside Bed Nets in Lilongwe, Malawi
Vaccine. 2020 Apr 30. LINK.
Bell GJ, Loop M, Topazian HM, ..., Hoffman I, Bailey JA, Emch M.

Selected Grants

T32-AI-102623 (S Mehta PI)
NIH/NIAID
Johns Hopkins HIV Epidemiology and Prevention Sciences Training Program
Role: Postdoctoral fellow
June 2024 – PresentF31-AI-167672 (GJ Bell PI)
NIH/NIAID
Epidemiological, Geospatial, and Phylogenetic Evidence to Inform Interventions Against HIV Transmission during Acute and Early HIV Infection in Lilongwe, Malawi
Role: Principal investigator
March 2022 – May 2024

Materials Freely Available Upon Request

Content
Day 1: Introduction to R
Day 2: Introduction to GIS
Day 3: GIS in R
Day 4: Developing intuition in epidemiology and statistics
Day 5: Advanced methods (clustering, spatial regression)