▁humans , ▁growing ▁to ▁a ▁length ▁of ▁up ▁to ▁. ▁It ▁is ▁one ▁of ▁several ▁species ▁of ▁As car is . ▁An ▁as car id ▁n emat ode ▁of ▁the ▁ph yl um ▁N emat oda , ▁it ▁is ▁the ▁most ▁common ▁par as it ic ▁w orm ▁in ▁humans . ▁This ▁organ ism ▁is ▁responsible ▁for ▁the ▁disease ▁asc arias is , ▁a ▁type ▁of ▁hel min th ias is ▁and ▁one ▁of ▁the ▁group ▁of ▁neglect ed ▁tropical ▁dise ases . ▁An ▁estimated ▁one - six th ▁of ▁the ▁human ▁population ▁is ▁inf ected ▁by ▁A . ▁lum br ico ides ▁or ▁another ▁round w orm . ▁As c arias is ▁is ▁pre val ent ▁world wide , ▁especially ▁in ▁tropical ▁and ▁subt rop ical ▁countries . ▁ ▁It ▁has ▁been ▁proposed ▁that ▁As car is ▁lum br ico ides ▁and ▁As car is ▁su um ▁( p ig ▁round w orm ) ▁are ▁the ▁same ▁species . ▁ ▁L ifecycle ▁▁ ▁As car is ▁lum br ico ides , ▁a ▁round w orm , ▁inf ect s ▁humans ▁via ▁the ▁f ec al - oral ▁route . ▁E gg s ▁released ▁by ▁adult ▁females ▁are ▁shed ▁in ▁f ec es . ▁Un fer til ized ▁eggs ▁are ▁often ▁observed ▁in ▁f ec al ▁samples ▁but ▁never ▁become ▁inf ect ive . ▁F ert il ized ▁eggs ▁emb ry on ate ▁and ▁become ▁inf ect ive ▁after ▁ 1 8 ▁days ▁to ▁several ▁weeks ▁in ▁soil , ▁depending ▁on ▁the ▁environmental