Predicting the epidemiological impact of antiretroviral allocation strategies in KwaZulu-Natal: The effect of the urban–rural divide

doi:10.1073/pnas.0509689103

Predicting the epidemiological impact of antiretroviral allocation strategies in KwaZulu-Natal: The effect of the urban–rural divide

*Semel Institute for Neuroscience and Human Behavior, and Department of Biomathematics, David Geffen School of Medicine, University of California, 1100 Glendon Avenue, Penthouse 2, Los Angeles, CA 90024; and
^‡University of California and San Francisco General Hospital, 995 Potrero Avenue, San Francisco, CA 94110

Edited by Burton H. Singer, Princeton University, Princeton, NJ, and approved July 12, 2006 (received for review November 21, 2005)

Abstract

Antiretroviral therapy (ART) is becoming available in South Africa. Demand will exceed supply; thus, difficult decisions will have to be made in allocating ART. The majority of those treated for HIV are likely to be in cities, because health infrastructure and personnel are concentrated in urban centers. We predict the epidemiological impact of drug allocation strategies (DAS) by using a spatially explicit model that links urban and rural epidemics. We parameterize our model by using data from the KwaZulu-Natal province in South Africa. We model the South African government's treatment plan from 2004–2008, and we predict the consequences of one DAS that allocates drugs only to Durban and of two DAS that allocate drugs to both urban and rural areas. All three strategies would treat 500,000 people by 2008. Not surprisingly, the Durban-only DAS would prevent the greatest number of infections (an additional 15,000 infections by 2008). However, it may have been expected that this DAS would generate the highest levels of transmitted resistance, because it concentrates ART in one location. Paradoxically, we found that this DAS would generate the lowest levels of transmitted resistance. Concentrating treatment in Durban would also avert the greatest number of AIDS-related deaths. We discuss the difference between using the principle of treatment equity versus using the principle of utilitarianism/efficiency to allocate ART. Decisions about allocating scarce drugs should consider treatment equity as well as epidemiological consequences. Notably, a Durban-only DAS would lead to new disparities in healthcare between urban and rural areas in KwaZulu-Natal.

Footnotes

^§To whom correspondence should be addressed. E-mail: sblower{at}mednet.ucla.edu
↵ ^†Present address: Complex Systems in Biology, Centre for Vascular Research, Faculty of Medicine, University of New South Wales, High Street, Kensington NSW 2052, Australia.
Author contributions: D.P.W. and S.M.B. designed research; D.P.W. and S.M.B. performed research; D.P.W., J.K., and S.M.B. analyzed data; D.P.W. and S.M.B. wrote the paper; and J.K. provided clinical expertise and parameter estimates from the literature.
Conflict of interest statement: No conflicts declared.
This paper was submitted directly (Track II) to the PNAS office.
Abbreviations:

ART,

antiretroviral therapy;

DAS,

drug allocation strategy/strategies;

PLWHA,

people living with HIV/AIDS.
Freely available online through the PNAS open access option.