Capillaria philippinensis is the causative agent of human intestinal capillariasis. It was first discovered in the Philippines in 1963. C. hepatica and C. aerophila are two other Capillaria spp. The adult worms continually weave in and out of the mucosa of the small intestines causing damage to the epithelium and submucosa.
Heavy infections can occur from autoinfection.
Patients experience diarrhea, abdominal pain, weight loss, weakness, and emaciation along with loses of proteins and electrolytes. Death may occur as a result of heart failure, low electrolytes, or secondary bacterial infections.