title: Mechanisms of host seeking by parasitic nematodes.
abstract: The phylum Nematoda comprises a diverse group of roundworms that includes parasites of vertebrates, invertebrates, and plants. Human-parasitic nematodes infect more than one billion people worldwide and cause some of the most common neglected tropical diseases, particularly in low-resource countries [1]. Parasitic nematodes of livestock and crops result in billions of dollars in losses each year [1]. Many nematode infections are treatable with low-cost anthelmintic drugs, but repeated infections are common in endemic areas and drug resistance is a growing concern with increasing therapeutic and agricultural administration [1]. Many parasitic nematodes have an environmental infective larval stage that engages in host seeking, a process whereby the infective larvae use sensory cues to search for hosts. Host seeking is a complex behavior that involves multiple sensory modalities, including olfaction, gustation, thermosensation, and humidity sensation. As the initial step of the parasite-host interaction, host seeking could be a powerful target for preventative intervention. However, host-seeking behavior remains poorly understood. Here we review what is currently known about the host-seeking behaviors of different parasitic nematodes, including insect-parasitic nematodes, mammalian-parasitic nematodes, and plant-parasitic nematodes. We also discuss the neural bases of these behaviors.
authors.affiliation: Department of Microbiology, Immunology, and Molecular Genetics and Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, United States. Electronic address: sgang@ucla.edu.
authors.forename: Spencer S
authors.initials: SS
authors.lastname: Gang
authors.affiliation: Department of Microbiology, Immunology, and Molecular Genetics and Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, United States. Electronic address: ehallem@microbio.ucla.edu.
authors.forename: Elissa A
authors.initials: EA
authors.lastname: Hallem
mesh_terms: D000818:Animals; D000072777:Host-Seeking Behavior; D006801:Humans; D009348:Nematoda / Q000502:physiology*; D010944:Plants
keywords: Entomopathogenic nematodes; Host-seeking behavior; Olfactory behavior; Parasitic helminths; Parasitic nematodes; Skin-penetrating nematodes