DISSERTATION RESEARCH: Larval stress and immunity of adult mosquitoes

Board Of Trustees Of Illinois State University, Normal IL

Investigators

Abstract

Pathogenic bacteria, viruses, fungi, and parasitic worms are often transmitted by vectors, commonly biting insects such as mosquitoes. Environmental stressors acting on mosquito larvae, including high density, food shortage, and extreme temperatures, can have lifelong impacts on adult biology; common manifestations are reduced survival, longevity, and body condition. Stressors may also enhance the physiological ability of adult mosquitoes to harbor and spread pathogens. This Doctoral Dissertation Improvement project pursues the mechanisms underlying the surprising result that stress during the larval stages of yellow fever mosquitoes actually enhances some aspects of general immunity, and produces adults with lower probability of spreading pathogens due to lower infection intensity and impaired body condition. The researchers will initiate laboratory experiments that manipulate larval density in order to quantify adult immune function, as red blood cell abundance and differentiation, vector susceptibility to parasite infection, and pathogen success. Results will elucidate general mechanisms by which stress alters insect immune systems and modifies interactions between insects and parasites. Diseases transmitted by mosquitoes include some of the most important human health threats in the world. Understanding the effects of environmental stress on larvae may be of practical importance, as the container mosquitoes in this study are vectors of human disease and are widely distributed in urban environments where the probability of contact with humans is high. This project will contribute to ongoing dissertation work that relies heavily on both undergraduate and graduate-level research assistance; undergraduates will gain valuable experience and may contribute to published research. Further, in-service high school math and science teachers from the Professional MA program in Environmental Science Education at Bradley University (Peoria, IL) participate in this body of work as a summer research immersion component of their degree program.