Yale School of Public Health, New Haven, Connecticut, United States of America.
PLoS Negl Trop Dis. 2012;6(8):e1799. doi: 10.1371/journal.pntd.0001799. Epub 2012 Aug 28.
A. aegypti production and human density may vary considerably in dengue endemic areas. Understanding how interactions between these factors influence the risk of transmission could improve the effectiveness of the allocation of vector control resources. To evaluate the combined impacts of variation in A. aegypti production and human density we integrated field data with simulation modeling.
METHODOLOGY/PRINCIPAL FINDINGS: Using data from seven censuses of A. aegypti pupae (2007-2009) and from demographic surveys, we developed an agent-based transmission model of the dengue transmission cycle across houses in 16 dengue-endemic urban 'patches' (1-3 city blocks each) of Armenia, Colombia. Our field data showed that 92% of pupae concentrated in only 5% of houses, defined as super-producers. Average secondary infections (R(0)) depended on infrequent, but highly explosive transmission events. These super-spreading events occurred almost exclusively when the introduced infectious person infected mosquitoes that were produced in super-productive containers. Increased human density favored R(0), and when the likelihood of human introduction of virus was incorporated into risk, a strong interaction arose between vector production and human density. Simulated intervention of super-productive containers was substantially more effective in reducing dengue risk at higher human densities.
SIGNIFICANCE/CONCLUSIONS: These results show significant interactions between human population density and the natural regulatory pattern of A. aegypti in the dynamics of dengue transmission. The large epidemiological significance of super-productive containers suggests that they have the potential to influence dengue viral adaptation to mosquitoes. Human population density plays a major role in dengue transmission, due to its potential impact on human-A. aegypti contact, both within a person's home and when visiting others. The large variation in population density within typical dengue endemic cities suggests that it should be a major consideration in dengue control policy.
埃及伊蚊的滋生地和人口密度在登革热流行地区可能有很大差异。了解这些因素之间的相互作用如何影响传播风险，可以提高病媒控制资源分配的有效性。为了评估埃及伊蚊滋生量和人口密度变化的综合影响，我们将现场数据与模拟模型相结合。
方法/主要发现：利用 2007-2009 年七次埃及伊蚊蛹的普查数据和人口调查数据，我们在哥伦比亚 Armenia16 个登革热流行城市“斑块”（每个斑块 1-3 个街区）的房屋之间建立了基于代理的登革热传播周期的传播模型。我们的现场数据表明，92%的蛹集中在只有 5%的房屋中，这些房屋被定义为超级滋生地。平均二次感染率（R0）取决于罕见但极具爆炸性的传播事件。这些超级传播事件几乎只发生在被引入的传染性个体感染了在超级滋生容器中产生的蚊子时。人口密度的增加有利于 R0，当病毒的人类引入可能性被纳入风险时，向量产生和人口密度之间出现了强烈的相互作用。模拟干预超级滋生容器在更高的人口密度下，大大降低了登革热风险。
意义/结论：这些结果表明，人口密度与埃及伊蚊自然调节模式之间存在显著的相互作用，这对登革热传播动态有重大影响。超级滋生容器具有重要的流行病学意义，这表明它们有可能影响登革热病毒对蚊子的适应。由于人口密度对人与人之间以及个体在自己家中与埃及伊蚊的接触的潜在影响，人口密度在登革热传播中起着主要作用。在典型的登革热流行城市中，人口密度的变化很大，这表明在登革热控制政策中应将其作为一个主要考虑因素。
