How Distance and Time Escalate the Risk of Acquiring HIV - Study RevealsGeneral

Professor Adrian Dobra, Professor Till Barninghausen, Professor Frank Tanser and Dr Alain Vandormael.Professor Adrian Dobra, Professor Till Barninghausen, Professor Frank Tanser and Dr Alain Vandormael.

Findings on human mobility, specifically, on how time (period) and space (distance) can pose added risks in acquiring HIV/AIDS, have been released following a study involving UKZN’s Professor Frank Tanser, a Professor in Epidemiology in the College of Health Sciences and a senior faculty researcher at the Africa Health Research Institute (AHRI).

‘This study is the very first mobility study to use complete geo-residential histories to quantify the space-time measurement of human mobility in relationship to the risk of HIV acquisition. These findings supported our key assumption that people who periodically change their residences over larger distances or spend larger periods of time outside their usual community are at a significantly higher risk of acquiring HIV/AIDS ’ said Tanser.

This population-based cohort study, conducted and sampled in a rural demographic surveillance setting in the north of KwaZulu-Natal, revealed that for migrating  men, a risk of acquiring HIV increased by 50% for a  migration distance of 40km whereas the risk of acquiring HIV in women migrating a distance of 109km increased by 50%.

These results indicate a clear but non–linear relationship between distance migrated and HIV acquisition. One of the surprising finding in this study is that even relatively short distance movements confer considerable addition of HIV risk in men.

The study is titled: “Space-Time Migration Patterns and Risk of HIV Acquisition in Rural South Africa”.

The research team comprised Tanser and three other internationally acclaimed epidemiologists and health systems researchers at the AHRI.

The study team analysed the space-time characteristics for more than 8 000 migration events over a 10-year period - representing a total of 1 028 782km travelled - for nearly 18 000 individuals who were HIV-negative at baseline.  The population-based cohort study heavily relied on detailed longitudinal socio demographic data and individual HIV surveillance data available at AHRI. This enabled researchers to look closely at sexual behaviours, socio demographics, and geo- and residential histories to ascertain causal relationships between differing mobility patterns and the subsequent risk of HIV acquisition.

This study has been published in the AIDS Journal by internationally acclaimed HIV researchers and authors respectively: (1.) Professor Adrian Dobra, an Associate Professor at the University of Washington; (2.) Professor Till Barninghausen, an Assistant Professor at the Department of Global Health and Population, Harvard T.H. Chan School of Public Health, and Senior faculty researcher and Programme Director in Health Systems and Impact at AHRI; (3.) Professor Frank Tanser, a Professor in Epidemiology in the Faculty of Health Sciences in UKZN and a senior faculty researcher at AHRI and (4.) Dr Alain Vandormael, an epidemiologist and statistician at AHRI.

Lihle Sosibo