Human infection most often occurs after ingestion of infected raw snake, frog, or pig. Water infected with larva in the tiny crustacean Cyclops may also be infectious. Contact with infected flesh of any of the intermediate hosts can cause infection and may spread beyond the initial site of infection.

Raw snake consumption, practiced during some Asian masculinity rituals, is one of the most common modes of transmission. Use of poultice containing raw frog can also transmit infection, sometimes causing orbital sparganosis.

In the Western hemisphere, water contamination is the most common cause of infection given the infrequency of raw snake consumption or poultice use.,