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Why do some people with ascariasis have few or no symptoms?
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infectious disease
Birds are the primary reservoirs of West Nile virus. The virus is transmitted to humans and horses by mosquitoes that have bitten infected birds.
Many individuals infected with ascariasis remain asymptomatic because the severity of the condition is typically linked to the worm burden, or the number of parasites present in the host. While the infection cycle involves larvae migrating through the liver and lungs, individuals with a low number of roundworms often do not experience noticeable clinical symptoms.1
In contrast, heavy infestations are more likely to cause significant health issues, such as malnutrition or intestinal obstruction, particularly in children. For those with light infections, the presence of the parasite may go entirely undetected until a worm is observed in the feces.1