Basu Sanjay, Friedland Gerald H, Medlock Jan, Andrews Jason R, Shah N Sarita, Gandhi Neel R, Moll Anthony, Moodley Prashini, Sturm A Willem, Galvani Alison P
Tugela Ferry Care and Research Collaboration, Tugela Ferry, KwaZulu-Natal 3010, South Africa.
Proc Natl Acad Sci U S A. 2009 May 5;106(18):7672-7. doi: 10.1073/pnas.0812472106. Epub 2009 Apr 13.
Extensively drug-resistant tuberculosis (XDR TB) has been detected in most provinces of South Africa, particularly in the KwaZulu-Natal province where several hundred cases have been reported since 2004. We analyzed the transmission dynamics of XDR TB in the region using mathematical models, and observed that nosocomial transmission clusters of XDR TB may emerge into community-based epidemics under the public health conditions of many South African communities. The effective reproductive number of XDR TB in KwaZulu-Natal may be around 2. Intensified community-based case finding and therapy appears critical to curtailing transmission. In the setting of delayed disease presentation and high system demand, improved diagnostic approaches may need to be employed in community-based programs rather than exclusively at tertiary hospitals. Using branching process mathematics, we observed that early, community-based drug-susceptibility testing and effective XDR therapy could help curtail ongoing transmission and reduce the probability of XDR TB epidemics in neighboring territories.
南非大部分省份都已检测到广泛耐药结核病（XDR-TB），尤其是夸祖鲁-纳塔尔省，自2004年以来已报告了数百例病例。我们使用数学模型分析了该地区XDR-TB的传播动态，观察到在许多南非社区的公共卫生条件下，XDR-TB的医院内传播集群可能演变成基于社区的流行病。夸祖鲁-纳塔尔省XDR-TB的有效再生数可能约为2。加强基于社区的病例发现和治疗对于遏制传播似乎至关重要。在疾病呈现延迟和系统需求高的情况下，可能需要在基于社区的项目中采用改进的诊断方法，而不是仅在三级医院使用。通过分支过程数学，我们观察到早期基于社区的药物敏感性检测和有效的XDR治疗有助于遏制正在进行的传播，并降低邻近地区发生XDR-TB流行的可能性。
