Discussion and revision of the mathematical modeling tool described in the previously published article Modeling HIV Transmission risk among Mozambicans prior to their initiating highly active antiretroviral therapy

Susan Cassels, Cynthia R. Pearson, Ann E. Kurth, Diane P. Martin, Jane M. Simoni, Eduardo Matediana, Stephen Gloyd

Research output: Contribution to journalArticle

Abstract

Mathematical models are increasingly used in social and behavioral studies of HIV transmission; however, model structures must be chosen carefully to best answer the question at hand and conclusions must be interpreted cautiously. In Pearson et al. (2007), we presented a simple analytically tractable deterministic model to estimate the number of secondary HIV infections stemming from a population of HIV-positive Mozambicans and to evaluate how the estimate would change under different treatment and behavioral scenarios. In a subsequent application of the model with a different data set, we observed that the model produced an unduly conservative estimate of the number of new HIV-1 infections. In this brief report, our first aim is to describe a revision of the model to correct for this underestimation. Specifically, we recommend adjusting the population-level sexually transmitted infection (STI) parameters to be applicable to the individual-level model specification by accounting for the proportion of individuals uninfected with an STI. In applying the revised model to the original data, we noted an estimated 40 infections/1000 HIV-positive persons per year (versus the original 23 infections/1000 HIV-positive persons per year). In addition, the revised model estimated that highly active antiretroviral therapy (HAART) along with syphilis and herpes simplex virus type 2 (HSV-2) treatments combined could reduce HIV-1 transmission by 72% (versus 86% according to the original model). The second aim of this report is to discuss the advantages and disadvantages of mathematical models in the field and the implications of model interpretation. We caution that simple models should be used for heuristic purposes only. Since these models do not account for heterogeneity in the population and significantly simplify HIV transmission dynamics, they should be used to describe general characteristics of the epidemic and demonstrate the importance or sensitivity of parameters in the model.

Original languageEnglish (US)
Pages (from-to)858-862
Number of pages5
JournalAIDS Care - Psychological and Socio-Medical Aspects of AIDS/HIV
Volume21
Issue number7
DOIs
StatePublished - Jul 2009

Fingerprint

mathematical modeling
Highly Active Antiretroviral Therapy
HIV Infections
HIV
Sexually Transmitted Diseases
HIV-1
Theoretical Models
Human Herpesvirus 2
Population Characteristics
Syphilis
Coinfection
Population
Hand
Therapeutics
human being
demographic situation

Keywords

  • HIV
  • Mathematical modeling
  • Prevention

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health
  • Health(social science)
  • Social Psychology

Cite this

Discussion and revision of the mathematical modeling tool described in the previously published article Modeling HIV Transmission risk among Mozambicans prior to their initiating highly active antiretroviral therapy. / Cassels, Susan; Pearson, Cynthia R.; Kurth, Ann E.; Martin, Diane P.; Simoni, Jane M.; Matediana, Eduardo; Gloyd, Stephen.

In: AIDS Care - Psychological and Socio-Medical Aspects of AIDS/HIV, Vol. 21, No. 7, 07.2009, p. 858-862.

Research output: Contribution to journalArticle

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