The cestodes (tapeworms) Taenia saginata (beef tapeworm) and T. solium (pork tapeworm). Taenia solium can also cause cysticercosis. Life Cycle:.[LastModified:][Taeniasaginata][Taeniasolium]CausalAgents:Thecestodes(tapeworms)Taeniasaginata(beeftapeworm)andT.solium(porktapeworm). Taeniasoliumcanalsocausecysticercosis.LifeCycle:LifecycleofTaeniasaginataandTaeniasoliumHumansaretheonlydefinitivehostsforTaeniasaginataandTaeniasolium. Eggsorgravidproglottidsarepassedwithfeces;theeggscansurvivefordaystomonthsintheenvironment. Cattle(T.saginata)andpigs(T.solium)becomeinfectedbyingestingvegetationcontaminatedwitheggsorgravidproglottids. Intheanimal'sintestine,theoncosphereshatch,invadetheintestinalwall,andmigratetothestriatedmuscles,wheretheydevelopintocysticerci. Acysticercuscansurviveforseveralyearsintheanimal. Humansbecomeinfectedbyingestingraworundercookedinfectedmeat. Inthehumanintestine,thecysticercusdevelopsover2monthsintoanadulttapeworm,whichcansurviveforyears. Theadulttapewormsattachtothesmallintestinebytheirscolexandresideinthesmallintestine. Lengthofadultwormsisusually5morlessforT.saginata(howeveritmayreachupto25m)and2to7mforT.solium. Theadultsproduceproglottidswhichmature,becomegravid,detachfromthetapeworm,andmigratetotheanusorarepassedinthestool(approximately6perday). T.saginataadultsusuallyhave1,000to2,000proglottids,whileT.soliumadultshaveanaverageof1,000proglottids. Theeggscontainedinthegravidproglottidsarereleasedaftertheproglottidsarepassedwiththefeces. T.saginatamayproduceupto100,000andT.soliummayproduce50,000eggsperproglottidrespectively.GeographicDistribution:Bothspeciesareworldwideindistribution. Taeniasoliumismoreprevalentinpoorercommunitieswherehumansliveinclosecontactwithpigsandeatundercookedpork,andinveryrareinMuslimcountries.Page1of2