School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK.
Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, Mathematics Institute and School of Life Sciences, University of Warwick, Coventry, UK.
J Infect Dis. 2020 Jun 11;221(Suppl 5):S503-S509. doi: 10.1093/infdis/jiz647.
The low prevalence levels associated with lymphatic filariasis elimination pose a challenge for effective disease surveillance. As more countries achieve the World Health Organization criteria for halting mass treatment and move on to surveillance, there is increasing reliance on the utility of transmission assessment surveys (TAS) to measure success. However, the long-term disease outcomes after passing TAS are largely untested. Using 3 well-established mathematical models, we show that low-level prevalence can be maintained for a long period after halting mass treatment and that true elimination (0% prevalence) is usually slow to achieve. The risk of resurgence after achieving current targets is low and is hard to predict using just current prevalence. Although resurgence is often quick (<5 years), it can still occur outside of the currently recommended postintervention surveillance period of 4-6 years. Our results highlight the need for ongoing and enhanced postintervention monitoring, beyond the scope of TAS, to ensure sustained success.
淋巴丝虫病消除所伴随的低流行水平给有效的疾病监测带来了挑战。随着越来越多的国家达到世界卫生组织停止大规模治疗的标准并转向监测，对传播评估调查（TAS）的效用的依赖程度也越来越高，以衡量成功。然而，通过 TAS 后长期的疾病结果在很大程度上未经检验。使用 3 个成熟的数学模型，我们表明，在停止大规模治疗后，低流行水平可以维持很长时间，而真正的消除（0%的流行率）通常很难实现。在达到当前目标后再次出现的风险较低，仅使用当前的流行率很难预测。尽管再次出现通常很快（<5 年），但它仍然可能发生在当前建议的干预后监测期（4-6 年）之外。我们的研究结果强调需要在 TAS 之外进行持续和强化的干预后监测，以确保持续成功。
