Ascariasis - Ascaris . Large and common, common with poor sanitation - especially where human waste is used for fertilizer. Large population of worms may be present without symptoms. Pinworms - enterobius . Fecal-oral mode of transmission.
Females crawls out of anus at night to lay eggs - itching.
If one child is infected, the rest of the family is also infected. Necator - present in US, New World Hookworm. Acquired by walking barefoot - larvae penetrated skin. Strongyloidiasis - Strongyloides . The threadworm - unlike other helminths will multiple in human host.