Silhol Romain, Gregson Simon, Nyamukapa Constance, Mhangara Mutsa, Dzangare Janet, Gonese Elizabeth, Eaton Jeffrey W, Case Kelsey K, Mahy Mary, Stover John, Mugurungi Owen
aDepartment of Infectious Disease Epidemiology, Imperial College London, London, UK bBiomedical Research and Training Institute, Avondale, Harare, Zimbabwe cAIDS and TB Unit, Zimbabwe Ministry of Health and Child Welfare, Harare, Zimbabwe dDivision of Global HIV and TB, U.S. Centers for Disease Control and Prevention, Harare, Zimbabwe eProgramme Branch, UNAIDS, Geneva, Switzerland fAvenir Health, Glastonbury, Connecticut, USA.
AIDS. 2017 Apr;31 Suppl 1(Suppl 1):S41-S50. doi: 10.1097/QAD.0000000000001418.
More cost-effective HIV control may be achieved by targeting geographical areas with high infection rates. The AIDS Impact model of Spectrum - used routinely to produce national HIV estimates - could provide the required subnational estimates but is rarely validated with empirical data, even at a national level.
The validity of the Spectrum model estimates were compared with empirical estimates.
Antenatal surveillance and population survey data from a population HIV cohort study in Manicaland, East Zimbabwe, were input into Spectrum 5.441 to create a simulation representative of the cohort population. Model and empirical estimates were compared for key demographic and epidemiological outcomes. Alternative scenarios for data availability were examined and sensitivity analyses were conducted for model assumptions considered important for subnational estimates.
Spectrum estimates generally agreed with observed data but HIV incidence estimates were higher than empirical estimates, whereas estimates of early age all-cause adult mortality were lower. Child HIV prevalence estimates matched well with the survey prevalence among children. Estimated paternal orphanhood was lower than empirical estimates. Including observations from earlier in the epidemic did not improve the HIV incidence model fit. Migration had little effect on observed discrepancies - possibly because the model ignores differences in HIV prevalence between migrants and residents.
The Spectrum model, using subnational surveillance and population data, provided reasonable subnational estimates although some discrepancies were noted. Differences in HIV prevalence between migrants and residents may need to be captured in the model if applied to subnational epidemics.
通过针对高感染率的地理区域，可能实现更具成本效益的艾滋病病毒防控。Spectrum的艾滋病影响模型——常用于生成全国艾滋病病毒估计数——可提供所需的次国家级估计数，但即使在国家层面，也很少用实证数据进行验证。
将Spectrum模型估计数的有效性与实证估计数进行比较。
将来自津巴布韦东部马尼卡兰省一项人群艾滋病病毒队列研究的产前监测和人口调查数据输入Spectrum 5.441，以创建一个代表该队列人群的模拟模型。对关键人口和流行病学结果的模型估计数与实证估计数进行比较。研究了数据可用性的替代方案，并对认为对次国家级估计数重要的模型假设进行了敏感性分析。
Spectrum估计数总体上与观察数据一致，但艾滋病病毒发病率估计数高于实证估计数，而早年全因成人死亡率估计数则较低。儿童艾滋病病毒流行率估计数与儿童调查流行率匹配良好。估计的父亲孤儿率低于实证估计数。纳入疫情早期的观察结果并未改善艾滋病病毒发病率模型的拟合度。迁移对观察到的差异影响不大——可能是因为该模型忽略了移民与居民之间艾滋病病毒流行率的差异。
使用次国家级监测和人口数据的Spectrum模型提供了合理的次国家级估计数，尽管存在一些差异。如果应用于次国家级疫情，可能需要在模型中考虑移民与居民之间艾滋病病毒流行率的差异。
