Partnership duration, concurrency, and HIV in sub-Saharan Africa
Authored by Larry Sawers, Alan Isaac
Date Published: 2017
DOI: 10.2989/16085906.2017.1336105
Sponsors:
No sponsors listed
Platforms:
Python
Model Documentation:
Other Narrative
Model Code URLs:
Model code not found
Abstract
A widely accepted explanation for the exceptionally high HIV prevalence
in sub-Saharan Africa is the practice of long-term overlapping
heterosexual partnering. This article shows that long-duration
concurrent partnering can be protective against HIV transmission rather
than promoting it. Monogamous partnering prevents sexual transmission to
anyone outside the partnership and, in an initially
concordant-seronegative partnership, prevents sexual acquisition of HIV
by either partner. Those protections against transmission and
acquisition last as long as the partnership persists without new outside
partnerships. Correspondingly, these two protective effects characterise
polygynous partnerships, whether or not the polygyny is formal or
informal, until a partner initiates a new partnership. Stable and
exclusive unions of any size protect against HIV transmission, and more
durable unions provide a longer protective effect. Survey research
provides little information on partnership duration in sub-Saharan
Africa and sheds no light on the interaction of duration, concurrency,
and HIV. This article shows how assumptions about partnership duration
in individual-based sexual-network models affect the contours of
simulated HIV epidemics. Longer mean partnership duration slows the pace
at which simulated epidemics grow. With plausible assumptions about
partnership duration and at levels of concurrency found in the region,
simulated HIV epidemics grow slowly or not at all. Those results are
consistent with the hypothesis that long-duration partnering is
protective against HIV and inconsistent with the hypothesis that
long-term concurrency drives the HIV epidemics in sub-Saharan Africa.
Tags
modelling
Infection
Individual-based modelling
Risk
population
Prevalence
Transmission dynamics
South-africa
Sub-saharan africa
Spread
Stage
Hiv/aids
Concurrency
Polygyny
Sexual partnerships