Alomar Abdullah A, Pérez-Ramos Daniel W, Kim Dongmin, Kendziorski Natalie L, Eastmond Bradley H, Alto Barry W, Caragata Eric P
Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, Vero Beach, FL, United States.
Front Microbiol. 2023 Mar 15;14:1138476. doi: 10.3389/fmicb.2023.1138476. eCollection 2023.
transinfections established in key mosquito vectors, including are typically associated with pathogen blocking-reduced susceptibility to infection with key pathogens and reduced likelihood those pathogens are transmitted to new hosts. Host-symbiont-virus interactions are less well understood in mosquitoes like , which naturally harbor , with pathogen blocking observed in some populations but not others, potentially due to innate differences in their load. In nature, mosquito larvae are often subject to developmental stresses associated with larval competition, which can lead to reduced body size and differential susceptibility to arbovirus infection.
In this study, we sought to understand whether competition stress and infection in combine to impact host fitness and susceptibility to infection with West Nile virus. We reared -infected and uninfected larvae under three competition stress levels, increasing larval density without increasing the amount of food supplied. We then monitored larval development and survival, measured wing length and quantified density in adults, and then challenged mosquitoes from each treatment group orally with West Nile virus.
We observed that high competition stress extended development time, decreased the likelihood of eclosion, decreased body size, and increased susceptibility to West Nile virus (WNV) infection. We also observed that infection reduced WNV load under low competition stress, and significantly improved the rate of survival for larval reared under higher competition stress. Consequently, our data suggest that native infection in has differential consequences for host fitness and susceptibility to WNV infection depending on competition stress.
在包括[具体蚊子种类]在内的关键蚊子媒介中建立的转染通常与病原体阻断有关，即对关键病原体感染的易感性降低，以及这些病原体传播给新宿主的可能性降低。在像[具体蚊子种类]这样的蚊子中，宿主-共生体-病毒相互作用的了解较少，它们自然携带[共生体名称]，在一些种群中观察到病原体阻断现象，而在其他种群中则没有，这可能是由于它们[共生体名称]负载的先天差异。在自然界中，蚊子幼虫经常受到与幼虫竞争相关的发育压力，这可能导致体型减小和对虫媒病毒感染的易感性差异。
在本研究中，我们试图了解[蚊子种类]中的竞争压力和[共生体名称]感染是否共同影响宿主适应性以及对西尼罗河病毒感染的易感性。我们在三种竞争压力水平下饲养感染和未感染[共生体名称]的[蚊子种类]幼虫，增加幼虫密度而不增加食物供应量。然后我们监测幼虫发育和存活情况，测量翅长并量化成虫中的[共生体名称]密度，接着用西尼罗河病毒对每个处理组的蚊子进行口服攻击。
我们观察到高竞争压力延长了发育时间，降低了羽化的可能性，减小了体型，并增加了对西尼罗河病毒（WNV）感染的易感性。我们还观察到[共生体名称]感染在低竞争压力下降低了WNV载量，并显著提高了在较高竞争压力下饲养的幼虫的存活率。因此，我们的数据表明，[蚊子种类]中天然的[共生体名称]感染对宿主适应性和对WNV感染的易感性有不同的影响，这取决于竞争压力。
