Intestinal helminths: Strongyloides stercoralis, Ascaris lumbricoides, hookworm, Trichuris trichiuria, Enterobius vermicularis, Trichinella, intestinal tapeworms, and liver flukes

This chapter focuses on intestinal helminthic infections among travelers. In contrast to protozoan parasites, most helminths do not multiply in humans (Strongyloides stercoralis being an exception), so repeated or prolonged exposure may be needed for acquisition of sufficiently high worm burdens for symptomatic infections to develop. However, significant morbidity from intestinal helminths can occur among travelers. The specific infections addressed include strongyloidiasis, ascariasis, hookworm infection, trichuriasis, enterobiasis, trichinellosis, taeniasis, and liver flukes. Although some of these organisms mainly cause gastrointestinal problems, others cause cutaneous reactions, respiratory symptoms, muscle pain, hepatobiliary complications, or allergic reactions. Helminthic infections are also frequently a cause of presentation with eosinophilia among travelers.