Role of direct and indirect social and spatial ties in the diffusion of HIV and HCV among people who inject drugs: a cross-sectional community-based network analysis in New Delhi, India
Department of Medicine, Division of Infectious Diseases, Johns Hopkins School of Medicine, Baltimore, United States
Shruti H Mehta
Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
Aylur K Srikrishnan
YR Gaitonde Centre for AIDS Research and Education (YRGCARE), Chennai, India
Katie JC Zook
Department of Medicine, Division of Infectious Diseases, Johns Hopkins School of Medicine, Baltimore, United States
Priya Duggal
Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
Shobha Mohapatra
YR Gaitonde Centre for AIDS Research and Education (YRGCARE), Chennai, India
Saravanan Shanmugam
YR Gaitonde Centre for AIDS Research and Education (YRGCARE), Chennai, India
Paneerselvam Nandagopal
YR Gaitonde Centre for AIDS Research and Education (YRGCARE), Chennai, India
Muniratnam S Kumar
YR Gaitonde Centre for AIDS Research and Education (YRGCARE), Chennai, India
Elizabeth Ogburn
Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
Gregory M Lucas
Department of Medicine, Division of Infectious Diseases, Johns Hopkins School of Medicine, Baltimore, United States
Carl A Latkin
Department of Health, Behavior, and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
Sunil S Solomon
Department of Medicine, Division of Infectious Diseases, Johns Hopkins School of Medicine, Baltimore, United States; Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
Background: People who inject drugs (PWID) account for some of the most explosive human immunodeficiency virus (HIV) and hepatitis C virus (HCV) epidemics globally. While individual drivers of infection are well understood, less is known about network factors, with minimal data beyond direct ties. Methods: 2512 PWID in New Delhi, India were recruited in 2017–19 using a sociometric network design. Sampling was initiated with 10 indexes who recruited named injection partners (people who they injected with in the prior month). Each recruit then recruited their named injection partners following the same process with cross-network linkages established by biometric data. Participants responded to a survey, including information on injection venues, and provided a blood sample. Factors associated with HIV/HCV infection were identified using logistic regression. Results: The median age was 26; 99% were male. Baseline HIV prevalence was 37.0% and 46.8% were actively infected with HCV (HCV RNA positive). The odds of prevalent HIV and active HCV infection decreased with each additional degree of separation from an infected alter (HIV AOR: 0.87; HCV AOR: 0.90) and increased among those who injected at a specific venue (HIV AOR: 1.50; HCV AOR: 1.69) independent of individual-level factors (p<0.001). In addition, sociometric factors, for example, network distance to an infected alter, were statistically significant predictors even when considering immediate egocentric ties. Conclusions: These data demonstrate an extremely high burden of HIV and HCV infection and a highly interconnected injection and spatial network structure. Incorporating network and spatial data into the design/implementation of interventions may help interrupt transmission while improving efficiency. Funding: National Institute on Drug Abuse and the Johns Hopkins University Center for AIDS Research.
