The itching will often lead to re-infection as the eggs are captured under the fingernails, and eventually reintroduced orally. The eggs can also be spread by air and other mechanisms eventually leading to oral introduction into the victim.
The condition can be treated with mebendazole (Vermox), piperazine (Antepar), or mostly commonly pyrantyl pamoate (Combatrin, Povan). Also great care should be taken to shower daily, and wash hands before every meal to avoid re-infection. All infected materials (pyjamas, bedclothes, and underwear) should be washed with soap and hot water daily.
The pinworm occurs worldwide, and in all socio-economic groups. However, it is more common in temperate regions, and among those with poor hygiene. 500 million infections are reported annually worldwide. 50% of children become infected at some point.
Some physicians also believe that pinworms can cause appendicitis, but that is unsubstantiated.