Kay B H, Fanning I D, Mottram P
Queensland Institute of Medical Research, Bramston Terrace, Herston, Australia.
Med Vet Entomol. 1989 Oct;3(4):415-22. doi: 10.1111/j.1365-2915.1989.tb00249.x.
Culex annulirostris Skuse mosquitoes (Brisbane strain) were reared at 20 degrees C or 27 degrees C and the adult females were experimentally infected by feeding Murray Valley encephalitis virus (MVE). They were then maintained (a) in the insectary at 20 degrees C, after rearing at either 20 degrees C or 27 degrees C; (b) at ambient outdoor temperatures, range 12.2-28.9 degrees C, mean 19.6 degrees C; or (c) at 27 degrees C after rearing at 27 degrees C. There was no significant difference in rates of MVE infection or transmission when mosquitoes were reared and maintained constantly at 20 degrees C or 27 degrees C. However, for females kept at reduced temperature (i.e. mean = 19.6 degrees C or 20 degrees C after rearing at 27 degrees C), the infection and transmission rates of MVE were significantly reduced (2 x 8 replicates). This investigation illustrates that vector competence is depressed by decreasing temperatures for adult mosquitoes compared with those they experienced during development. Similar patterns were evident with previously published work on Japanese and St Louis encephalitis, dengue and yellow fever. The process appears to be reversible, i.e. increased temperature raises virus infection and transmission rates. It is concluded that, without incubation at warmer temperatures, flavivirus recovery from overwintering mosquitoes will be negatively biased.
环喙库蚊（布里斯班品系）在20摄氏度或27摄氏度的环境中饲养，成年雌蚊通过喂食墨累谷脑炎病毒（MVE）进行实验性感染。然后，将它们（a）在20摄氏度的昆虫饲养室中饲养，此前饲养温度为20摄氏度或27摄氏度；（b）置于室外环境温度下，范围为12.2 - 28.9摄氏度，平均温度为19.6摄氏度；或（c）在27摄氏度饲养后保持在27摄氏度。当蚊子在20摄氏度或27摄氏度下持续饲养和维持时，MVE的感染率和传播率没有显著差异。然而，对于在较低温度下饲养的雌蚊（即27摄氏度饲养后平均温度为19.6摄氏度或20摄氏度），MVE的感染率和传播率显著降低（2×8次重复）。这项研究表明，与发育期间经历的温度相比，成年蚊子的媒介能力会因温度降低而受到抑制。在先前发表的关于日本脑炎、圣路易斯脑炎、登革热和黄热病的研究中也有类似的模式。这个过程似乎是可逆的，即温度升高会提高病毒感染率和传播率。得出的结论是，如果没有在温暖温度下进行孵化，从越冬蚊子中恢复黄病毒的结果将产生负面偏差。
