Life Cycle
In humans, the hypothesized life cycle is as follows: Ingestion of contaminated food, water, or infected dung beetle. Infects upper esophagus, moves around and lays eggs in buccal cavity of human host, ingested eggs locate near esophagus, develop and mature into adult worms after two subsequent molting stages, migrate into buccal cavity, no eggs are ever found in human feces, which strengthens the assumption that humans are solely incidental, accidental, and dead end hosts for the Gongylonema pulchrum parasite life cycle.
The G. pulchrum parasite has also been studied in vivo in rabbits. The life cycle is as follows:
Infective third stage larva from naturally infected dung beetles (intermediate hosts and vectors), were orally given to rabbits. The larvae entered the upper gastrointestinal tract of the rabbits (esophagus and upper stomach), and then migrated upward into the buccal cavity- pharyngeal mucosa and tongue. A third molt took place 11 days after primary infection, and the final molt took place at 36 days after primary infection. Worms reached sexual maturity at about 8 weeks, and were found mostly in the esophagus of the rabbit. 72–81 days post primary infection, embryonated eggs appeared in the feces of the rabbits.
Read more about this topic: Gongylonema Pulchrum
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