从美国的西尼罗河病毒感染到中国的登革热

西尼罗河病毒于1937年在乌干达的西尼罗河区发现。早年在非洲、欧洲、中东和西亚时有流行,1999年侵入北美。首发为62例脑膜脑炎伴有肌肉无力的患者,其中7例死亡,后鉴定为蚊传西尼罗河病毒感染。在接下来的数年里,病毒感染迅速蔓延至美国本土48州。病例报道在2003年达到高峰9 862例。截至2017年底,总病例达到48 070例,2 138例死亡。重灾区是加利福尼亚,科罗拉多,德克萨斯,内布拉斯加和伊利诺州。目前西尼罗河病毒在美洲分布于从加拿大到委内瑞拉的广泛地区。该病毒已经深植于流行区的生态系统里,局部暴发流行风险犹存。登革热作为一种传统的蚊媒病近年来在全球范围内大幅上升, 究其原因似可归咎于人口流动、货物运输、气候变化、疫苗缺乏、媒介抗药等因素。中国南方省区成为重灾区之一。媒介综合治理似乎不能有效地控制登革热流行的深度和广度。美国在西尼罗河病毒感综合治理的经验对于我国和其它地区登革热和其它蚊媒病的控制有重要借鉴意义。这些经验包括常态化、策略性媒介检测-研发和推广实用、方便、价格合理的媒介检测工具用于不同生理状态的重要蚊种的检测;同等重要是高敏感、高特异、快速、批量样品病原检测技术的研发和应用,从而掌握病毒的时间和空间分布;最后是基于生物理性措施的媒介综合防治,即应用基于微生物和昆虫生长调节剂的绿色环保蚊媒控制产品,结合环境治理以达到理想效果。

From West Nile virus infection in the USA to dengue fever in China

The West Nile virus (WNV) was first identified in 1937 in West Nile District, Uganda. Endemics and epidemics occurred from time to time in Africa, Europe, Middle East and West Asia ever since. This virus invaded North America (New York City) in 1999, starting from 62 cases of meningoencephalitis associated with muscle weakness, which resulted in 7 fatalities. During the following years, the WNV rapidly spread to the continental 48 states with a peak in 2003 when 9 862 cases were reported. As of end of 2017, in total 48 070 cases with 2 238 fatalities were documented. The states that were impacted the most were California, Colorado, Texas, Nebraska and Illinois. Currently the WNV exists in the vast area between Canada and Venezuela in the Americas. It is believed that the WNV has been deeply imbedded into the ecological systems in North America, and risk of endemics and epidemics reasonably warrants. Dengue fever, as one of the most common mosquito-borne illness, re-emerged or resurged significantly during the recent decades, largely due to human migration, freight exchanges, climatic changes, lack of vaccine, pesticide resistance in vector species, etc. The areas in southern China suffered the same. It appeared that local vector control practice did not adequately suppressed the epidemics of dengue. The experience in integrated management of the WNV infection in the USA is amendable to the management of dengue and other vector-borne disease in China and elsewhere worldwide. First, it must be emphasized to develop and promote practical, convenient, affordable vector surveillance tools to target vectors of different physiological statuses in species of concern. The equally important approach is to implement highly sensitive, specific, rapid and high output pathogen detection technology to monitor the spatial and temporal distribution of the viruses. Ultimately, integrated vector management by biorational approaches must be in place to include environmental management and application of pesticides based on microbial organisms, insect growth regulators and others.