Newton E A, Farley J D, Gayle C
Special Program on Sexually Transmitted Diseases, Caribbean Epidemiology Centre (CAREC/PAHO/WHO), Port of Spain, Trinidad, West Indies.
J Acquir Immune Defic Syndr Hum Retrovirol. 1996 Jan 1;11(1):69-76. doi: 10.1097/00042560-199601010-00009.
In this study we estimated past human immunodeficiency virus (HIV) incidence in 19 nations in the primarily English-speaking Caribbean and projected the course of the epidemic to the year 1999. We compared the results obtained from several different models of HIV incidence and different assumed incubation distributions. Linear and nonlinear optimization methods were used to fit several models (power, logistic, spline, and step) to adult (age 15 years or older) AIDS incidence data derived from our existing surveillance system. All four models tested gave good fits to the data, with estimates of cumulative HIV incidence in 1993 ranging from 16,504 to 21,732. An increase in the assumed median of the AIDS incubation distribution by one year increased the estimates of current cumulative adult HIV incidence by approximately 12%; these estimates varied by as much as 6% between models. An adjustment of the data for possible reporting delay increased the estimates by approximately 7% and for underreporting by 25%. Despite their sensitivity to underlying assumptions, back-projection estimates provide useful insights into the patterns of HIV and AIDS incidence. The models indicate that HIV and AIDS incidences in the English-speaking Caribbean have been rising steadily, with adult HIV prevalence in the general population still less than 1%.
在本研究中，我们估计了主要讲英语的加勒比地区19个国家过去的人类免疫缺陷病毒（HIV）发病率，并预测了该流行病到1999年的发展趋势。我们比较了从几种不同的HIV发病率模型以及不同的假定潜伏期分布所获得的结果。运用线性和非线性优化方法，将几种模型（幂函数、逻辑斯蒂、样条和阶梯模型）与从我们现有的监测系统得出的成人（15岁及以上）艾滋病发病率数据进行拟合。所测试的所有四种模型都与数据拟合良好，1993年累积HIV发病率的估计值在16,504至21,732之间。将艾滋病潜伏期分布的假定中位数增加一年，使当前累积成人HIV发病率的估计值增加了约12%；这些估计值在不同模型之间的差异高达6%。对可能的报告延迟进行数据调整使估计值增加了约7%，对漏报情况进行调整则使估计值增加了25%。尽管回溯估计对基本假设敏感，但它能为HIV和艾滋病发病率模式提供有用的见解。模型表明，讲英语的加勒比地区HIV和艾滋病发病率一直在稳步上升，普通人群中成人HIV患病率仍低于1%。
