, Volume 48, Issue 4, pp 1401–1428 | Cite as

Marital Shopping and Epidemic AIDS

  • Jeremy R. Magruder


HIV risks decline sharply at age 30 for women in South Africa, long before coital frequencies or pregnancies decrease. I evaluate several prominent behavioral models of HIV, and find that these do not suggest sharply decreasing risks with age. I formulate a model of spousal search and find that “marital shopping” can generate epidemic HIV prevalence despite low transmission rates because search behavior interacts with dynamics of HIV infectiousness. The implied age-infection profile closely mimics that in South Africa, and the suggested behavior matches that reported by South Africans. Condom use in new relationships and transmission rate reductions are both found to be effective policies and, when used together, eliminate the potential of spousal search to spread HIV. In contrast, antiretroviral treatment is found to have only a minimal effect on the epidemic.


Behavioral epidemiology HIV/AIDS Spousal search 



I am indebted to Fabian Lange, Ethan Ligon, Ted Miguel, Nicoli Nattrass, Emily Oster, Rohini Pande, Claus Portner, Paul Schultz, Jeremy Seekings, Chris Udry, Damien de Walque; and seminar participants at Yale, Berkeley, Harvard, the University of Washington, and the University of Cape Town for many helpful suggestions. All mistakes are naturally my own.

Supplementary material

13524_2011_60_MOESM1_ESM.pdf (119 kb)
ESM 1 (PDF 118 kb)


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Copyright information

© Population Association of America 2011

Authors and Affiliations

  1. 1.University of California, BerkeleyBerkeleyUSA

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