Platt K B, Linthicum K J, Myint K S, Innis B L, Lerdthusnee K, Vaughn D W
Department of Microbiology, Immunology, and Preventive Medicine, Iowa State University, Ames 50011-3222, USA.
Am J Trop Med Hyg. 1997 Aug;57(2):119-25. doi: 10.4269/ajtmh.1997.57.119.
In addition to heavily infecting the salivary glands of Aedes aegypti (L.) mosquitoes, dengue viruses produce a significant infection of the nervous system, involving the brain, Johnston's organ, compound eye, and thoracic and abdominal ganglion. To determine if dengue infection affects feeding behavior of Ae. aegypti we measured feeding times, counted the number of feeding delays or interruptions, and by in situ immunocytochemistry techniques determined the spatial and temporal distribution of dengue infections in females parenterally infected with dengue 3 virus. The mean of the total time required for feeding by infected mosquitoes was significantly longer than the time required by uninfected mosquitoes. Similarly, the mean of the time spent probing was significantly longer in infected mosquitoes than in uninfected mosquitoes when day after inoculation was considered. Significant increases in the length of feeding activity in infected mosquitoes corresponded to virus infection in organs that are known to control or influence activities associated with blood feeding. Sequential infections of the salivary glands (five days postinoculation [PI]), brain and compound eye (eight days PI), and Johnston's organ and midgut and abdominal ganglion (11 days PI) of most mosquitoes were observed. The increased time required by infected Ae. aegypti mosquitoes to acquire a blood meal may contribute to the efficiency of Ae. aegypti as a vector of dengue virus. Longer feeding periods are more likely to be interrupted by the host, which increases the chance that an infected mosquito will probe or feed on additional hosts.
除了严重感染埃及伊蚊的唾液腺外，登革病毒还会对神经系统造成显著感染，累及大脑、约翰斯顿器官、复眼以及胸神经节和腹神经节。为了确定登革热感染是否会影响埃及伊蚊的取食行为，我们测量了取食时间，统计了取食延迟或中断的次数，并通过原位免疫细胞化学技术确定了经登革3病毒皮下感染的雌性埃及伊蚊体内登革热感染的时空分布。感染蚊子取食所需的总时间平均值显著长于未感染蚊子所需的时间。同样，考虑接种后天数时，感染蚊子的探测时间平均值也显著长于未感染蚊子。感染蚊子取食活动时间的显著增加与已知控制或影响与血液摄取相关活动的器官中的病毒感染相对应。观察到大多数蚊子的唾液腺（接种后5天）、大脑和复眼（接种后8天）以及约翰斯顿器官、中肠和腹神经节（接种后11天）依次受到感染。感染的埃及伊蚊获取血餐所需时间的增加可能有助于提高埃及伊蚊作为登革病毒传播媒介的效率。更长的取食时间更有可能被宿主打断，这增加了感染蚊子探测或叮咬其他宿主的机会。
