Analyzing Spatial Movement Patterns and Transmission Hotspots to Inform Targeted Case-Finding Interventions in KwaZulu-Natal, South Africa

PROJECT SUMMARY/ABSTRACT
Background. Global tuberculosis (TB) incidence has only decreased incrementally – despite concerted efforts
to understand TB transmission patterns in high-prevalence settings. As TB exhibits pronounced spatial
heterogeneity in high-incidence settings like South Africa, spatially targeted case-finding approaches may be
effective. Although the underlying processes giving rise to spatial heterogeneity remain unclear, individual
mobility and assortative patterns likely underlie areas of heightened TB transmission. Understanding spatial
mobility patterns may provide insights into the mechanisms that generate and interconnect hotspots within a
community, guiding future active case-finding approaches. Aims. In line with NIAID Strategic Priorities for
Tuberculosis Research, this study will 1) characterize forms of spatial mobility and their association with recent
transmission and 2) examine the relationship between spatial mobility subclasses and community-based TB
transmission hotspots. Elucidating these gaps will advance our understanding of local transmission and inform
the development of targeted case-finding interventions to curb ongoing TB transmission in endemic settings.
Approach. Since there is a limited understanding of the mobility patterns of TB patients, this research will use
detailed mobility data (i.e., the frequency, duration, and spatial dimensions) from TARGET-TB, an ongoing
population-based epidemiologic study that enrolls all incident TB cases identified in a peri-urban community in
KwaZulu-Natal, South Africa, to identify individuals, groups, and places where control efforts may be targeted.
Furthermore, advances in genomic statistical modeling have greatly enhanced our understanding of transmission
linkages at various spatial scales. This contextual setting presents a unique opportunity to combine detailed
spatial mobility data with bacterial whole genome sequencing data to understand the relationship between spatial
mobility and recent transmission and identify transmission hotspots. The overarching goal is to provide insights
into local transmission mechanisms to inform targeted case-finding strategies. Training. Ms. Bezuidenhout’s
training plan leverages her quantitative abilities and TB research experience to advance her skills and launch
her career as an independent investigator focused on spatial mobility and TB transmission. Her training goals
are to develop in-depth knowledge of spatial mobility, advance her expertise in molecular epidemiology and TB
transmission inference, learn advanced epidemiologic techniques for missing data, and build capacity for
effective research dissemination. Under the guidance of her Primary Sponsor, Ms. Bezuidenhout will receive
tailored mentorship from a team of experienced TB researchers who work with the parent study, conduct spatial-
and molecular-focused research, and have tremendous expertise in the requisite quantitative methods. Training
will take place at Columbia University, a high-caliber institution with specialized research programs in population
health, infectious disease, and spatial and social epidemiology.

Grant Number: 1F31AI186450-01A1
NIH Institute/Center: NIH
Principal Investigator: Dana Bezuidenhout