HIV treatment as prevention : systematic comparison of mathematical models of the potential impact of antiretroviral therapy on HIV incidence in South Africa

Simple item page
dc.contributor.authorEaton, Jeffrey W.
dc.contributor.authorJohnson, Leigh F.
dc.contributor.authorSalomon, Joshua A.
dc.contributor.authorBarnighausen, Till
dc.contributor.authorBendavid, Eran
dc.contributor.authorBershteyn, Anna
dc.contributor.authorBloom, David E.
dc.contributor.authorCambiano, Valentina
dc.contributor.authorFraser, Christophe
dc.contributor.authorHontelez, Jan A. C.
dc.contributor.authorHumair, Salal
dc.contributor.authorKlein, Daniel J.
dc.contributor.authorLong, Elisa F.
dc.contributor.authorPhillips, Andrew N.
dc.contributor.authorPretorius, Carel
dc.contributor.authorStover, John
dc.contributor.authorWenger, Edward A.
dc.contributor.authorWilliams, Brian G.
dc.contributor.authorHallett, Timothy B.
dc.date.accessioned2013-02-26T09:47:09Z
dc.date.available2013-02-26T09:47:09Z
dc.date.issued2012-07
dc.descriptionThe original publication is available at www.plosmedicine.orgen_ZA
dc.description.abstractBackground: Many mathematical models have investigated the impact of expanding access to antiretroviral therapy (ART) on new HIV infections. Comparing results and conclusions across models is challenging because models have addressed slightly different questions and have reported different outcome metrics. This study compares the predictions of several mathematical models simulating the same ART intervention programmes to determine the extent to which models agree about the epidemiological impact of expanded ART. Methods and Findings: Twelve independent mathematical models evaluated a set of standardised ART intervention scenarios in South Africa and reported a common set of outputs. Intervention scenarios systematically varied the CD4 count threshold for treatment eligibility, access to treatment, and programme retention. For a scenario in which 80% of HIV-infected individuals start treatment on average 1 y after their CD4 count drops below 350 cells/ml and 85% remain on treatment after 3 y, the models projected that HIV incidence would be 35% to 54% lower 8 y after the introduction of ART, compared to a counterfactual scenario in which there is no ART. More variation existed in the estimated long-term (38 y) reductions in incidence. The impact of optimistic interventions including immediate ART initiation varied widely across models, maintaining substantial uncertainty about the theoretical prospect for elimination of HIV from the population using ART alone over the next four decades. The number of person-years of ART per infection averted over 8 y ranged between 5.8 and 18.7. Considering the actual scale-up of ART in South Africa, seven models estimated that current HIV incidence is 17% to 32% lower than it would have been in the absence of ART. Differences between model assumptions about CD4 decline and HIV transmissibility over the course of infection explained only a modest amount of the variation in model results. Conclusions: Mathematical models evaluating the impact of ART vary substantially in structure, complexity, and parameter choices, but all suggest that ART, at high levels of access and with high adherence, has the potential to substantially reduce new HIV infections. There was broad agreement regarding the short-term epidemiologic impact of ambitious treatment scale-up, but more variation in longer term projections and in the efficiency with which treatment can reduce new infections. Differences between model predictions could not be explained by differences in model structure or parameterization that were hypothesized to affect intervention impact.en_ZA
dc.description.versionPublishers' versionen_ZA
dc.format.extent20 p. : ill.
dc.identifier.citationEaton, J. W. et al. 2012. HIV Treatment as Prevention: Systematic Comparison of Mathematical Models of the Potential Impact of Antiretroviral Therapy on HIV Incidence in South Africa. PLoS Med, 9(7): e1001245, doi:10.1371/journal.pmed.1001245.en_ZA
dc.identifier.issn1549-1676 (online)
dc.identifier.issn1549-1277 (print)
dc.identifier.otherdoi:10.1371/journal.pmed.1001245
dc.identifier.urihttp://hdl.handle.net/10019.1/79612
dc.language.isoen_ZAen_ZA
dc.publisherPublic Library of Science -- PLOSen_ZA
dc.rights.holderAuthors retain copyrighten_ZA
dc.subjectAIDS (Disease) - Treatment -- South Africaen_ZA
dc.subjectAntiretroviral therapy -- South Africa -- Mathematical modelsen_ZA
dc.titleHIV treatment as prevention : systematic comparison of mathematical models of the potential impact of antiretroviral therapy on HIV incidence in South Africaen_ZA
dc.typeArticleen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
eaton_hiv_2012.pdf
Size:
416.6 KB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
1.95 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Research Articles (Health Systems and Public Health)