| Roundworm |
Means of Infection |
| Hookworm (Ancylostoma duodenale and Necator americanus) |
Contact with soil-based juveniles; common in southern states |
| Pinworm (Enterobius vermicularis) |
Inhalation of dust that contains ova and by contamination with fingers; most common worm parasite in United States |
| Intestinal roundworm (Ascaris lumbricoides) |
Ingestion of embryonated ova in contaminated food; common in rural Appalachia and southeastern states |
| Trichina worm (Trichinella spiralis) |
Ingestion of infected meat; occurs occasionally in humans throughout North America |
