F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America.
Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America.
PLoS Negl Trop Dis. 2019 Jan 28;13(1):e0007127. doi: 10.1371/journal.pntd.0007127. eCollection 2019 Jan.
Program decision-making for trachoma elimination currently relies on conjunctival clinical signs. Antibody tests may provide additional information on the epidemiology of trachoma, particularly in regions where it is disappearing or elimination targets have been met.
A cluster-randomized trial of mass azithromycin distribution strategies for trachoma elimination was conducted over three years in a mesoendemic region of Niger. Dried blood spots were collected from a random sample of children aged 1-5 years in each of 24 study communities at 36 months after initiation of the intervention. A multiplex bead assay was used to test for antibodies to two Chlamydia trachomatis antigens, Pgp3 and CT694. We compared seropositivity to either antigen to clinical signs of active trachoma (trachomatous inflammation-follicular [TF] and trachomatous inflammation-intense [TI]) at the individual and cluster level, and to ocular chlamydia prevalence at the community level.
Of 988 children with antibody data, TF prevalence was 7.8% (95% CI 6.1 to 9.5) and TI prevalence was 1.6% (95% CI 0.9 to 2.6). The overall prevalence of antibody positivity to Pgp3 was 27.2% (95% CI 24.5 to 30), and to CT694 was 23.7% (95% CI 21 to 26.2). Ocular chlamydia infection prevalence was 5.2% (95% CI 2.8 to 7.6). Seropositivity to Pgp3 and/or CT694 was significantly associated with TF at the individual and community level and with ocular chlamydia infection and TI at the community level. Older children were more likely to be seropositive than younger children.
Seropositivity to Pgp3 and CT694 correlates with clinical signs and ocular chlamydia infection in a mesoendemic region of Niger.
ClinicalTrials.gov NCT00792922.
目前，针对沙眼消除的项目决策依赖于结膜临床体征。抗体检测可能会提供关于沙眼流行病学的更多信息，特别是在沙眼正在消失或消除目标已经实现的地区。
在尼日尔的一个中流行地区，进行了一项为期三年的大规模阿奇霉素分布策略消除沙眼的集群随机试验。在干预开始 36 个月后，从每个研究社区的 1-5 岁儿童中随机抽取一个样本，采集干血斑。使用多指标珠状检测法检测两种沙眼衣原体抗原 Pgp3 和 CT694 的抗体。我们比较了个体和群体水平上两种抗原的血清阳性率与活动性沙眼（沙眼滤泡性炎症[TF]和沙眼强烈炎症[TI]）的临床体征，以及社区水平上的眼衣原体流行率。
在 988 名有抗体数据的儿童中，TF 流行率为 7.8%（95%CI 6.1-9.5），TI 流行率为 1.6%（95%CI 0.9-2.6）。Pgp3 抗体阳性的总体流行率为 27.2%（95%CI 24.5-30），CT694 为 23.7%（95%CI 21-26.2）。眼衣原体感染的流行率为 5.2%（95%CI 2.8-7.6）。Pgp3 和/或 CT694 的血清阳性与个体和社区水平的 TF 以及社区水平的眼衣原体感染和 TI 显著相关。年龄较大的儿童比年龄较小的儿童更有可能呈血清阳性。
在尼日尔的一个中流行地区，Pgp3 和 CT694 的血清阳性与临床体征和眼衣原体感染相关。
ClinicalTrials.gov NCT00792922。
