Cama Anaseini, Müller Andreas, Taoaba Raebwebwe, Butcher Robert M R, Itibita Iakoba, Migchelsen Stephanie J, Kiauea Tokoriri, Pickering Harry, Willis Rebecca, Roberts Chrissy H, Bakhtiari Ana, Le Mesurier Richard T, Alexander Neal D E, Martin Diana L, Tekeraoi Rabebe, Solomon Anthony W
International Agency for the Prevention of Blindness, Western Pacific Region, Suva, Fiji.
The Fred Hollows Foundation, Sydney, Australia.
PLoS Negl Trop Dis. 2017 Sep 12;11(9):e0005863. doi: 10.1371/journal.pntd.0005863. eCollection 2017 Sep.
In some Pacific Island countries, such as Solomon Islands and Fiji, active trachoma is common, but ocular Chlamydia trachomatis (Ct) infection and trachomatous trichiasis (TT) are rare. On Tarawa, the most populous Kiribati island, both the active trachoma sign "trachomatous inflammation-follicular" (TF) and TT are present at prevalences warranting intervention. We sought to estimate prevalences of TF, TT, ocular Ct infection, and anti-Ct antibodies on Kiritimati Island, Kiribati, to assess local relationships between these parameters, and to help determine the need for interventions against trachoma on Kiribati islands other than Tarawa.
As part of the Global Trachoma Mapping Project (GTMP), on Kiritimati, we examined 406 children aged 1-9 years for active trachoma. We collected conjunctival swabs (for droplet digital PCR against Ct plasmid targets) from 1-9-year-olds with active trachoma, and a systematic selection of 1-9-year-olds without active trachoma. We collected dried blood spots (for anti-Pgp3 ELISA) from all 1-9-year-old children. We also examined 416 adults aged ≥15 years for TT. Prevalence of TF and TT was adjusted for age (TF) or age and gender (TT) in five-year age bands.
The age-adjusted prevalence of TF in 1-9-year-olds was 28% (95% confidence interval [CI]: 24-35). The age- and gender-adjusted prevalence of TT in those aged ≥15 years was 0.2% (95% CI: 0.1-0.3%). Twenty-six (13.5%) of 193 swabs from children without active trachoma, and 58 (49.2%) of 118 swabs from children with active trachoma were positive for Ct DNA. Two hundred and ten (53%) of 397 children had anti-Pgp3 antibodies. Both infection (p<0.0001) and seropositivity (p<0.0001) were strongly associated with active trachoma. In 1-9-year-olds, the prevalence of anti-Pgp3 antibodies rose steeply with age.
Trachoma presents a public health problem on Kiritimati, where the high prevalence of ocular Ct infection and rapid increase in seropositivity with age suggest intense Ct transmission amongst young children. Interventions are required here to prevent future blindness.
在一些太平洋岛国，如所罗门群岛和斐济，活动性沙眼很常见，但眼部沙眼衣原体（Ct）感染和沙眼性倒睫（TT）却很罕见。在基里巴斯人口最多的塔拉瓦岛，活动性沙眼体征“沙眼性炎症-滤泡型”（TF）和TT的患病率都很高，需要进行干预。我们试图估算基里巴斯圣诞岛TF、TT、眼部Ct感染和抗Ct抗体的患病率，评估这些参数之间的局部关系，并帮助确定除塔拉瓦岛之外的基里巴斯其他岛屿是否需要开展沙眼干预措施。
作为全球沙眼地图绘制项目（GTMP）的一部分，在圣诞岛，我们对406名1-9岁儿童进行了活动性沙眼检查。我们从患有活动性沙眼的1-9岁儿童以及系统选取的无活动性沙眼的1-9岁儿童中采集了结膜拭子（用于针对Ct质粒靶点的液滴数字PCR）。我们从所有1-9岁儿童中采集了干血斑（用于抗Pgp3 ELISA）。我们还对416名15岁及以上的成年人进行了TT检查。TF和TT的患病率按五岁年龄组进行年龄（TF）或年龄及性别（TT）调整。
1-9岁儿童经年龄调整后的TF患病率为28%（95%置信区间[CI]：24-35）。15岁及以上人群经年龄和性别调整后的TT患病率为0.2%（95%CI：0.1-0.3%）。在193份来自无活动性沙眼儿童的拭子中，26份（13.5%）Ct DNA呈阳性，在118份来自有活动性沙眼儿童的拭子中，58份（49.2%）呈阳性。397名儿童中有210名（53%）有抗Pgp3抗体。感染（p<0.0001）和血清阳性（p<0.0001）均与活动性沙眼密切相关。在1-9岁儿童中，抗Pgp3抗体的患病率随年龄急剧上升。
沙眼在圣诞岛构成了一个公共卫生问题，眼部Ct感染的高患病率以及血清阳性率随年龄的快速上升表明幼儿中Ct传播活跃。这里需要采取干预措施以预防未来的失明。
