Parasitic diseases of insects

Abstract

Parasites of insects represent an exceptionally diverse group of organisms with equally varied lifecycles and adaptations. This chapter focuses primarily, but not exclusively, on the protozoan, helminth, and arthropod parasites of insects. Lethal and sub-lethal effects of parasitism are considered and especially in bee species these are considered alongside anthropogenic and environmental stressors that render insects more susceptible to infection. Parasites of insects are also notable for inducing host behavioural changes, some of which represent spectacular manipulative adaptations that favour parasite transmission. The infection and infestation of insects by parasites is a subject well represented in the published literature and it is understandably dominated by studies on commercially important insects such as honeybees and pests such as mosquitoes. This chapter, however, also identifies many neglected areas of research, such as the fascinating and often highly virulent entomopathogenic ciliates and amoebae that have considerable potential as biopesticides. The expanding commercial exploitation of diverse mass-reared insect taxa is stimulating further research into previously neglected areas of insect parasitology and the incorporation of ‘omic’-assisted technologies is at last allowing the complex host-parasite relationships in disease states to be teased apart.