Class Cestoidea Taenia solium,Taenia saginata Class Cestoidea, classification A- Intestinal cestode :live in the lumen of intestine:eg Taenia saginata Taenia solium Hymenolepis nana B- Tissue cestodes: present within the tissue (liver,lung,bone....) Cysticercosis Hydatid disease Class Cestoidea chacterstics 1- flattened 2-ribbon like 3- formed of: -scolex:head -Neck -segments : immature,mature,gravid (carry eggs) Scolex and segments Segments of tape worms Taenia saginata beef tape worm Disease: Taeniasis Distribution : all over the world Morphology : -Adult :4-6 meter, scolex with 4 suckers, no hooks,neck,mature segments,gravid segments -Egg:spheroid,yellowish brown,radially striated -Cystocericus bovis : larva of the worm,oval Adult Taenia Life cycle 1- adult in the small intestine (definitive host) 2-Mature eggs and gravid segments pass with feces ( diagnostic stage) 3- eggs ingested by cattle ( intermediate host) and converted into Cystocericus bovis (infective stage) 4- The definitive host is infected by ingestion of undercooked meat ( mode of infection) Cystocericus bovis in infected meat Signs and symptoms 1- hunger pain,indigestion,diarrhoea 2-intestinal obstruction 3- loss of weight 4- anexiety Diagnosis 1- Finding eggs in stool (dignostic stage) 2- Finding gravid segment in stool (dignostic stage) Diagnostic stage (Taenia egg) Diagnostic stage ( Taenia gravid segment) Treatment 1- Niclosamide ( 2 gm) chewed and swallowed with a little amount of water 2- saline purge 1 hour after treatment (some worms die and can cause cycticercosis) 3- avoid drugs that cause nausea or vomiting (eggs may reach to stomach,hatch,cause cysticercosis) Very important cysticercosis Definition :Infection with the larval stage of Taenia Occurs with Taenia solium species ONLY Its egg can penetrate the human intestinal wall and reach internal organs like liver,lung,brain leading to serious damage to these organs Very important cysticercosis This occurs by: 1- ingestion of raw food contaminated with pigs or human stool containing eggs 2- auto infection:internal,if the patient take emetic drugs,eggs pass to stomach,penetrate intestinal wall External feco-oral:lack of personal hygiene,person transmittes eggs from anus to mouth by contaminated hands,reach to stomach,penetrate intestinal wall Taenia solium (pork tapeworm) Point of comparisonTaenia saginataTaenia solium Geographical distributionAll over the worldIn pigs raising countries,not in islamic countries Morphology4-6 meter Scolex with no hooks 2-4 meter Scolex with hooks eggssimilar Definitive hostMan Intermediate hostcattlePigs, Man Mode of infectionIngestion of under cooked beef Ingestion of under cooked pork DiseaseTaeniasisTaeniasis, Cystocercosis ( ingestion of eggs) Taenia saginata scolex Taenia solium scolex Prevention and control A- prevention of taeniasis: 1-stop contamination of cattle raising areas by human feces 2- inspection of meat for cysticerci st slaughter houses Proper meat cooking ( at least foe 56 C) OR Freezing at -10 C for 10 days. Prevention and control B- prevention of CYSTICERCOSIS (INFECTION BY THE LARVAL STAGE) 1- Human feces should not be used as fertilizer 2- avoid eating contaminated raw vegetables 3- fast treatment of infected patient to prevent auto infection