Universitat de Girona, Girona, Catalunya, Spain.
San Francisco Public Health Department, San Francisco, California, USA.
Sci Rep. 2017 Jul 25;7(1):6464. doi: 10.1038/s41598-017-06619-9.
The number of reported early syphilis cases in San Francisco has increased steadily since 2005. It is not yet clear what factors are responsible for such an increase. A recent analysis of the sexual contact network of men who have sex with men with syphilis in San Francisco has discovered a large connected component, members of which have a significantly higher chance of syphilis and HIV compared to non-member individuals. This study investigates whether it is possible to exploit the existence of the largest connected component to design new notification strategies that can potentially contribute to reducing the number of cases. We develop a model capable of incorporating multiple types of notification strategies and compare the corresponding incidence of syphilis. Through extensive simulations, we show that notifying the community of the infection state of few central nodes appears to be the most effective approach, balancing the cost of notification and the reduction of syphilis incidence. Additionally, among the different measures of centrality, the eigenvector centrality reveals to be the best to reduce the incidence in the long term as long as the number of missing links (non-disclosed contacts) is not very large.
自 2005 年以来，旧金山报告的早期梅毒病例数量稳步增加。目前尚不清楚是什么因素导致了这种增加。最近对旧金山患有梅毒的男男性接触者的性接触网络进行了分析，发现了一个很大的连通组件，其中的成员感染梅毒和 HIV 的几率明显高于非成员个体。本研究探讨是否可以利用最大连通组件的存在来设计新的通知策略，从而有可能有助于减少病例数量。我们开发了一个能够结合多种通知策略的模型，并比较了相应的梅毒发病率。通过广泛的模拟，我们表明通知少数中心节点的感染状态似乎是最有效的方法，平衡了通知成本和梅毒发病率的降低。此外，在不同的中心性度量中，特征向量中心性显示在长期内是减少发病率的最佳方法，只要缺失链路（未公开的接触）的数量不是非常大。
