Ascaris lumbricoides is the human Ascaris parasite.  The parasite can be 10 inches to a foot long. Highest prevalence is in the tropical and subtropical regions.  Mostly found in areas with poor sanitation.  Can occur in the rural areas of southeastern United States. 

Life CycleEdit

Adults are in lumen of small intestine, deposit eggs in feces. Eggs hatch in newly infected host, larvae move from small intestine, into liver, then heart, lungs, up bronchii, swallowed, then back to small intestine.


Adult worms usually do not cause acute symptoms.  However, some may cause stunted growth.  High worm concentrations may cause abdominal pain and intestinal obstruction.  During the lung phase of larval migrartion, pulmonary symptoms may occur; cough, dyspnea..