Ascaris lumbricoides, the most frequent human intestinal nematode, is the causative agent of
ascariasis, with an estimated worldwide prevalence of over one billion people, especially in moist tropical and subtropical regions, but also in cooler climates. Although characterised with low morbidity and mortality rates, the global prevalence of
ascariasis still results in approximately 20,000 deaths annually, primarily as a consequence of
intestinal obstruction. In humans, transmission usually occurs by hand-to-mouth route by way of contaminated agricultural products and food, or from dirty hands. Three phases of
ascariasis may be present, namely, the pulmonary, intestinal and the complications stage. Although generally asymptomatic, heavy infestation may cause serious
pulmonary disease, or partial or complete obstruction of biliary or intestinal tracts. Anthelminthic
chemotherapy is required to eradicate the parasites and prevent potentially serious complications.
Mebendazole,
albendazole and
pyrantel pamoate are the most widely used agents to treat
ascariasis. Preventive
chemotherapy delivered to communities in endemic regions may serve as an affordable and cost-effective strategy to reduce the prevalence and morbidity in endemic regions. Under unusual circumstances, Ascaris suum, the cause of helminthic
infection in pigs, may also cause disease in humans.