Laboratoire de Lutte contre les Maladies Infectieuses, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech, Morocco.
Laboratory of Bacteriology-Virology, Avicienne Hospital Military, Marrakech, Morocco.
Transbound Emerg Dis. 2022 May;69(3):1466-1478. doi: 10.1111/tbed.14113. Epub 2021 May 5.
Rift Valley Fever (RVF) and West Nile virus (WNV) are two important emerging Arboviruses transmitted by Aedes and Culex mosquitoes, typically Ae. caspius, Ae. detritus and Cx. pipiens in temperate regions. In Morocco, several outbreaks of WNV (1996, 2003 and 2010), affecting horses mostly, have been reported in north-western regions resulting in the death of 55 horses and one person cumulatively. Serological evidence of WNV local circulation, performed one year after the latest outbreak, revealed WNV neutralizing bodies in 59 out of 499 tested participants (El Rhaffouli et al., 2012). The country also shares common borders with northern Mauritania, where RVF is often documented. Human movement, livestock trade, climate changes and the availability of susceptible mosquito vectors are expected to increase the spread of these diseases in the country. Thus, in this study, we gathered a data set summarizing occurrences of Ae. caspius, Ae. detritus and Cx. pipiens in the country, and generated model prediction for their potential distribution under both current and future (2050) climate conditions, as a proxy to identify regions at-risk of RVF and WNV probable expansion. We found that the north-western regions (where the population is most concentrated), specifically along the Atlantic coastline, are highly suitable for Ae. caspius, Ae. detritus and Cx. pipiens, under present-day conditions. Future model scenarios anticipated possible range changes for the three mosquitoes under all climatic assumptions. All of the studied species are prospected to gain new areas that are currently not suitable, even under the most optimist scenario, thus placing additional human populations at risk. Our maps and predictions offer an opportunity to strategically target surveillance and control programmes. Public health officials, entomological surveillance and control delegation must augment efforts and continuously monitor these areas to reduce and minimize human infection risk.
裂谷热（RVF）和西尼罗河病毒（WNV）是两种重要的新兴虫媒病毒，由埃及伊蚊和致倦库蚊传播，在温带地区通常为埃及伊蚊、埃及斑蚊和致倦库蚊。在摩洛哥，西北部地区曾报告过几次 WNV 疫情（1996 年、2003 年和 2010 年），主要影响马，累计导致 55 匹马和 1 人死亡。在最新疫情发生一年后进行的血清学证据显示，在 499 名测试参与者中有 59 人具有 WNV 中和抗体（El Rhaffouli 等人，2012 年）。该国还与经常发生裂谷热的毛里塔尼亚北部接壤。人类活动、牲畜贸易、气候变化和易感蚊子媒介的存在预计将增加这些疾病在该国的传播。因此，在这项研究中，我们收集了一个汇总该国埃及伊蚊、埃及斑蚊和致倦库蚊发生情况的数据组，并根据当前和未来（2050 年）气候条件生成了它们潜在分布的模型预测，以确定裂谷热和 WNV 可能扩张的高风险区域。我们发现，人口最集中的西北部地区，特别是沿大西洋海岸线，在当前条件下非常适合埃及伊蚊、埃及斑蚊和致倦库蚊。未来的模型情景预计，在所有气候假设下，这三种蚊子的范围都可能发生变化。所有研究的物种都有可能获得新的区域，即使在最乐观的情况下，目前不适合它们生存的区域也将获得新的区域，从而使更多的人口面临风险。我们的地图和预测为有针对性地开展监测和控制计划提供了机会。公共卫生官员、昆虫学监测和控制代表团必须加强努力，不断监测这些地区，以降低和最小化人类感染风险。
