sanjean
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>>The eggs hatch in the duodenum (i.e., first part of the small intestine).[20] The emerging pinworm larvae grow rapidly to a size of 140 to 150 micrometers in size,[19] and migrate through the small intestine towards the colon.[8] During this migration they moult twice and become adults.[8][10] Females survive for 5 to 13 weeks, and males about 7 weeks.[8] The male and female pinworms mate in the ileum (i.e., last part of the small intestine),[8] whereafter the male pinworms usually die,[20] and are passed out with stool.[15] The gravid female pinworms settle in the ileum, caecum (i.e., beginning of the large intestine), appendix and ascending colon,[8] where they attach themselves to the mucosa[10] and ingest
colonic contents. The gravid female pinworms migrate through the colon towards the rectum at a rate of 12 to 14 centimeters per hour.<<
So, the adults are alive and mating for weeks before they emerge from the rectum. The Vermox should kill the adults and there should be some kind of interval after ingesting the Vermox to when the next batch of eggs hatch and they have had time to become adults, mate and then to come out on the anus.