The Carter Center, Owerri, Nigeria.
The Carter Center, Atlanta, Georgia.
Am J Trop Med Hyg. 2018 Jul;99(1):116-123. doi: 10.4269/ajtmh.18-0163. Epub 2018 May 10.
Ivermectin treatment can cause central nervous system adverse events (CNS-AEs) in persons with very high-density microfilaremia (≥ 30,000 mf/mL blood). Hypoendemic onchocerciasis areas where is endemic have been excluded from ivermectin mass drug administration programs (MDA) because of the concern for CNS AEs. The rapid assessment procedure for (RAPLOA) is a questionnaire survey to assess history of eye worm. If ≥ 40% of respondents report eye worm, this correlates with ≥ 2% prevalence of very high-density loiasis microfilaremia, posing an unacceptable risk of CNS-AEs after MDA. In 2016, we conducted a study in 110 ivermectin-naïve, suspected onchocerciasis hypoendemic villages in southern Nigeria. In previous RAPLOA surveys these villages had prevalences between 10% and 67%. We examined 10,605 residents using the LoaScope, a cell phone-based imaging device for rapidly determining the microfilaria (mf) density of infections. The mean village mf prevalence was 6.3% (range 0-29%) and the mean individual mf count among positives was 326 mf/mL. The maximum individual mf count was only 11,429 mf/mL, and among 2,748 persons sampled from the 28 villages with ≥ 40% RAPLOA, the ≥ 2% threshold of very high mf density could be excluded with high statistical confidence ( < 0.01). These findings indicate that ivermectin MDA can be delivered in this area with extremely low risk of -related CNS-AEs. We also concluded that in Nigeria the RAPLOA survey methodology is not predictive of ≥ 2% prevalence of very high-density microfilaremia.
伊维菌素治疗可能会导致高密度微丝蚴血症（≥ 30,000 mf/mL 血液）患者出现中枢神经系统不良事件（CNS-AEs）。由于对 CNS AEs 的担忧，低度流行的盘尾丝虫病流行地区已被排除在伊维菌素大规模药物治疗方案（MDA）之外。 快速评估程序（RAPLOA）是一项问卷调查，用于评估眼部蠕虫的历史。如果≥ 40%的受访者报告有眼部蠕虫，这与≥ 2%的高密度罗阿丝虫微丝蚴患病率相关，在 MDA 后存在不可接受的 CNS-AE 风险。2016 年，我们在尼日利亚南部 110 个未经伊维菌素治疗、疑似盘尾丝虫病低度流行的村庄进行了一项研究。在之前的 RAPLOA 调查中，这些村庄的患病率在 10%至 67%之间。我们使用 LoaScope 对 10605 名居民进行了检查，LoaScope 是一种基于手机的成像设备，用于快速确定感染的微丝蚴（mf）密度。平均村庄 mf 患病率为 6.3%（范围 0-29%），阳性者的平均个体 mf 计数为 326 mf/mL。个体 mf 计数的最大值仅为 11429 mf/mL，在从 28 个 RAPLOA 阳性率≥ 40%的村庄中抽取的 2748 人中，非常高的 mf 密度≥ 2%的阈值可以以高统计学置信度排除（< 0.01）。这些发现表明，在该地区可以使用伊维菌素 MDA，而极低的 CNS-AE 风险与盘尾丝虫病相关。我们还得出结论，在尼日利亚，RAPLOA 调查方法不能预测≥ 2%的高密度微丝蚴血症患病率。
