Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA; Department of Infectious Disease Epidemiology, Imperial College London, London, UK.
Int J Parasitol Drugs Drug Resist. 2018 Apr;8(1):67-69. doi: 10.1016/j.ijpddr.2017.12.004. Epub 2018 Jan 13.
The egg reduction rate (ERR) is the current standard mean to assess the efficacy of drugs against human soil-transmitted helminths (STHs; Ascaris lumbricoides, Trichuris trichiura and hookworm). Although the timing of post-treatment sampling is pivotal for a readily interpretation of drug efficacy, there is lack empirical data that allows recommending the optimal time point for a follow-up egg counting. In the present study, we re-analyzed both the kinetics of worm expulsion and egg output for Ascaris lumbricoides following a single oral dose of albendazole in a series of studies previously conducted in Kenyan communities. The results indicate that it takes up to 10 days post-treatment before the expulsion of both adult male and female Ascaris worms is completed, approximately 20% of the worms being expelled between day 7 and 10 post-treatment. The sequential analysis of the egg out put, indicated a poor ERR (89.4%) at day 7 post-treatment, but a 100% ERR at day 14 and 21 post-treatment. Based on our findings we recommend to wait at least 14 days after an albendazole treatment before conducting the follow-up egg count. Any sampling before this time point may result in biased ERR estimates, due the release of residual eggs from moribund or degenerating worms.
卵减少率（ERR）是目前评估药物抗人体土源性线虫（蛔虫、鞭虫和钩虫）疗效的标准方法。尽管治疗后采样时间对于药物疗效的解释至关重要，但缺乏允许推荐后续卵计数最佳时间点的经验数据。在本研究中，我们重新分析了先前在肯尼亚社区进行的一系列研究中单次口服阿苯达唑后蛔虫的驱蛔动力学和产卵情况。结果表明，在治疗后 10 天内，雌雄蛔虫成虫才能完全排出体外，约有 20%的蛔虫在治疗后第 7 天至第 10 天排出体外。卵排出的顺序分析表明，治疗后第 7 天 ERR 较差（89.4%），而治疗后第 14 天和第 21 天 ERR 为 100%。基于我们的发现，我们建议在阿苯达唑治疗后至少等待 14 天再进行后续的卵计数。在此之前进行任何采样都可能导致 ERR 估计值存在偏差，因为濒死或退化的蠕虫会释放残留的卵。
