AIDS and Behavior

, Volume 16, Issue 7, pp 1746–1752 | Cite as

Is Concurrency Driving HIV Transmission in Sub-Saharan African Sexual Networks? The Significance of Sexual Partnership Typology

Commentary

Abstract

Recently, there has been debate about the role of concurrent partnerships in driving the transmission of HIV, particularly in Southern Africa, where HIV prevalence is up to 25 % in many heterosexual populations and where evidence from sexual behavior surveys also suggests high levels of male concurrency. While mathematical modeling studies have shown that concurrency has the potential to enhance the speed at which HIV spreads in a population, empirical studies up to now have failed to provide conclusive evidence supportive of these effects. Here we discuss some reasons for the apparent discrepancy between theoretical and empirical studies. We propose that studying the impact of concurrency on HIV transmission should be differentiated by taking more insight from social and behavioral studies on sexual partnerships into account. We also suggest that a more rigorous definition is needed for when a factor is considered a driving force for HIV epidemic spread. We illustrate this with a modeling example.

Keywords

Concurrent partnerships HIV transmission Sub-Saharan Africa Sexual networks Mathematical models Basic reproduction number 

Resumen

Reciéntemente se ha debatido el rol que las parejas concurrentes tienen en impulsar la transmisión de VIH, particularmente en Sudáfrica, donde la prevalencia en muchas poblaciones heterosexuales es de hasta 25 % y la evidencia de comportamiento sexual también sugiere altos niveles de concurrencia en hombres. Mientras que estudios con modelos matemáticos muestran que la concurrencia tiene el potencial de aumentar la velocidad de propagación de VIH en la población, hasta ahora estudios empíricos no han logrado mostrar evidencia concluyente sobre estos efectos. Aquí discutimos algunas razones de la aparente discrepancia entre los estudios teóricos y empíricos. Proponemos que estudios sobre el impacto de la concurrencia en la transmisión de VIH se deberían diferenciar considerando mayor entendimiento proveniente de estudios sociales y conductuales sobre parejas sexuales. También proponemos que se necesita una definición más rigurosa para cuando un factor se considera fuerza impulsora de propagación de una epidemia de VIH. Empleamos un modelo para ilustrar un ejemplo.

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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Julius Centre for Health Sciences and Primary CareUniversity Medical Centre UtrechtUtrechtThe Netherlands
  2. 2.Centre for Infectious Disease ControlRIVMBilthovenThe Netherlands
  3. 3.Department of Social SciencesFree University of BrusselsBrusselsBelgium

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