Assessment of transmission in trachoma programs over time suggests no short-term loss of immunity.
Assessment of transmission in trachoma programs over time suggests no short-term loss of immunity.
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DOI：
10.1371/journal.pntd.0002303
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发表时间：
2013
影响因子：
3.8
通讯作者：
West SK
中科院分区：
文献类型：
--
作者：
Liu F;Porco TC;Ray KJ;Bailey RL;Mkocha H;Muñoz B;Quinn TC;Lietman TM;West SK
沙眼项目极大地降低了导致该疾病的眼衣原体的患病率。一些人假设，由于计划成功地降低了感染的发生率，对感染的免疫力可能会降低，然后传播可能会增加。为了验证这一假设，有必要对多个社区进行纵向研究。在这里，我们使用基于抗生素治疗计划的第一、第二和第三年32个社区的估计基本繁殖数来量化传播。我们发现，随着时间的推移，基本繁殖数量几乎没有增加。基本繁殖数的线性趋势为- 0.025 /年，95% CI为- 0.167 ~ 0.117 /年。我们找不到证据证明在三年的项目中有任何免疫丧失。这是令人鼓舞的，因为它使反复大规模分发抗生素有可能消除甚至受影响最严重地区的感染。沙眼是由眼部沙眼衣原体反复感染引起的，是世界上最常见的致盲传染性疾病。沙眼的治疗包括在整个社区大规模使用阿奇霉素治疗。为了降低感染流行率，世界卫生组织（世卫组织）提倡在受影响地区每年至少三次在社区范围内分发口服抗生素，并根据沙眼的流行情况进一步进行大规模治疗。沙眼项目极大地降低了社区感染的流行率，一些人认为，感染流行率的降低可能导致免疫力的降低，而免疫力的降低可能反过来导致感染传播的增加。在这里，我们使用随机传播模型来分析从3年抗生素治疗计划（坦桑尼亚32个社区的集群随机临床试验）收集的数据，以评估在消除运动期间传播是否实际上增加。我们没有发现任何证据支持在项目过程中传播的增加。随着流行率的下降，短期内传播没有增加，这对沙眼规划来说是个好消息。
Trachoma programs have dramatically reduced the prevalence of the ocular chlamydia that cause the disease. Some have hypothesized that immunity to the infection may be reduced because of program success in reducing the incidence of infection, and transmission may then increase. Longitudinal studies of multiple communities would be necessary to test this hypothesis. Here, we quantify transmission using an estimated basic reproduction number based on 32 communities during the first, second, and third years of an antibiotic treatment program. We found that there is little to no increase in the basic reproduction number over time. The estimated linear trend in the basic reproduction number, , was found to be −0.025 per year, 95% CI −0.167 to 0.117 per year. We are unable to find evidence supporting any loss of immunity over the course of a 3-year program. This is encouraging, as it allows the possibility that repeated mass antibiotic distributions may eliminate infection from even the most severely affected areas. Trachoma, caused by repeated infections by the ocular strains of Chlamydia trachomatis, is the most common infectious cause of blindness in the world. Treatment for trachoma includes mass azithromycin treatments to the entire community. To reduce the prevalence of infection, the World Health Organization (WHO) advocates at least three annual community-wide distributions of oral antibiotics in affected areas, with further mass treatments based on the prevalence of trachoma. Trachoma programs have dramatically reduced the community prevalence of infection, and some have argued that lowered prevalence of infection may lead to reductions in immunity, and that less immunity may in turn lead to increased transmission from what infection remains. Here, we used a stochastic transmission model to analyze data collected from a 3-year antibiotic treatment program (a 32-community, cluster-randomized clinical trial in Tanzania) to assess whether or not transmission actually increases during elimination campaigns. We found no evidence supporting any increase in transmission over the course of the program. The absence of a short term increase in transmission as the prevalence decreases is good news for trachoma programs.
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影响因子：
168.9
作者：
West, SK;Munoz, B;Mabey, DCW
通讯作者：
Mabey, DCW
影响因子：
120.7
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Chidambaram, JD;Alemayehu, W;Lietman, TM
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Lietman, TM
冈比亚和坦桑尼亚的沙眼患病率和相关危险因素：整群随机对照试验的基线结果。
影响因子：
3.8
作者：
Harding-Esch, Emma M.;Edwards, Tansy;Mkocha, Harran;Munoz, Beatriz;Holland, Martin J.;Burr, Sarah E.;Sillah, Ansumana;Gaydos, Charlotte A.;Stare, Dianne;Mabey, David C. W.;Bailey, Robin L.;West, Sheila K.
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West, Sheila K.
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120.7
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Atik, Berna;Thanh, Ton Ton Kim;Dean, Deborah
通讯作者：
Dean, Deborah
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168.9
作者：
Schachter, J;West, SK;Faal, H
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Faal, H