Medical Parasitology and Immunology Lecture Notes PDF

MEDICAL PARASITOLOGY AND IMMUNOLOGY ONE HEALTH SUBTOPIC SUBSUBSUB List 1 ○ List 2 List 3 KUNG GUSTO NIYU LANG GAMITIN go lang di ako magaling sa mga estetik  MEDICAL PARASITOLOGY AND IMMUNOLOGY WHAT IS THE RELEVAN...

MEDICAL PARASITOLOGY AND IMMUNOLOGY ONE HEALTH SUBTOPIC SUBSUBSUB List 1 ○ List 2 List 3 KUNG GUSTO NIYU LANG GAMITIN go lang di ako magaling sa mga estetik  MEDICAL PARASITOLOGY AND IMMUNOLOGY WHAT IS THE RELEVANCE OF THIS APPROACH? - Many of the same microbes infect animals and humans, as they share the ecosystem they live ONE HEALTH in - Efforts by just one sector cannot prevent or Approach to designing and implementing programs, eliminate the problem policies, legislation, and research in which multiple - A well-coordinated approach in humans and in sectors communicate and work together to achieve animals is required to effectively contain the better public health outcomes transmission - We can contain the transmission if we know HOW it is transmitted WHO MAKES THE ONE HEALTH APPROACH WORK? - Professionals with a range of expertise and One health approach is relevant to the following areas active in different sectors of work: - Epidemiological data and laboratory Food safety information should be shared across sectors to Control of zoonoses effectively detect, respond to, and prevent Combating antibiotic resistance outbreaks of zoonoses and foof safety ○ Organisms that used to be susceptible problems to antibiotics but due to exposure they - Multi-sectoral responses must be promoted adapt; gene mutation ○ Antiobiotic stewardship: proper use of SUSTAINABLE DEVELOPMENT GOALS antibiotics (there are antibiotics that are only susceptible to gram-positive or gram-negative bacteria) - Set by the United Nations in 2012 ○ Antivirals - Aims to produce a set of universal goals that meet the urgent environmental, political, and economic challenges facing the world - Different sectors of the society work together to achieve these goals - Culture & tradition: ex. Eating raw fish  GOOD HEALTH AND WELL-BEING - Water from “poso” should be clean (boiled/ filtered out) - Cerebral malaria; hydrocephalus - Latrine/Proper toilet - Target of SDG 3 is end of epidemics - Community Medicine: proper sewage system to prevent diseases from spreading (ex. fecal material) QUALITY EDUCATION - Cleanliness, Sanitation, and Hygiene PARTNERSHIPS FOR THE GOALS - As early as childhood, education should be of good quality - Pandemic affected education in the Philippines - Quality health advocacy education - Debt crisis: lumaki utang ng PH, especially during the pandemic CLEAN WATER AND SANITATION - Partnerships with private institutions for community welfare - 20 NTDs (Neglected Tropical Diseases) - Priority diseases identified by the World Health Organization - 1 Billion - People worldwide infected by at least one NTD and living in impoverished settings “The Bottom Billion” INTRODUCTION TO PARASITOLOGY Bacterial vaginosis Vaginal Candidiasis Trichomonas Vaginalis PARASITOLOGY Area of biology concerned with the phenomenon of dependence of one living organism on another ○ Medical parasitology - is concerned primarily with parasites that affect humans and their medical significance as well as their importance in human Elephantiasis communities. ○ Tropical medicine - is a branch of medicine that deals with tropical diseases and other special medical problems of tropical regions TROPICAL DISEASE It is an illness that is indigenous to or endemic. incomplete sir pabalik Many tropical diseases are parasitic diseases Malaria - caused by plasmodium ○ Less because DOH eliminated some; Mindoro - disease is still active ○ Not totally eradicated ○ Prominent ỉn mountainous areas Entamoeba hystolytica ○ Amoebiasis ○ Characteristics of stool: greenish to mucoid (sometimes with blood) sige ○ Presence of protozoans Trichomonas (Trichomoniasis) Taenia Saginata - beef tapeworm  Taenia Solium - pork tapeworm 2. Intermediate host - harbors the asexual or Fasciola - liver larval stage of the parasite Mycobacterium Leprae - leprosy, ketong 3. Paratenic host - one in which the parasite Lymphatic filariasis - elephantiasis does not develop further to later stages. Rabies: virus However, the parasite remains alive and is able Scabies: mites; active sa gabi to infect another susceptible host Schistosomiasis- Taeniasis/Cysticercosis - raw VECTORS soil transmitted helminth - tapeworm Responsible for transmitting the parasites from one host to another SYMBIOSIS Living together of unlike organisms; may also SOURCES OF INFECTION: involve protection or other advantages to one 1. Contaminated soil and water or both organisms 2. Lack of sanitary toilets and the use of night soil or human excreta as fertilizers Forms of symbiosis: 3. Contaminated food Commensalism - two species live together and 4. Arthropods that serve as vectors (Ticks) one species benefits from the relationship 5. Beddings, clothings (fomites) without harming or benefiting the other 6. Food handlers ○ Ex. Entamoeba coli in intestinal lumen Mutualism - two organisms mutually benefit MODES OF TRANSMISSION: from each other 1. Foodborne ○ Ex. Termites and flagellates in their 2. Skin penetration (cutaneous larva migrants) digestive system) 3. Bites of arthropods vectors (mosquitos) Parasitism - one organism (parasite) lives in 4. Congenital transmission or one another, depending on the latter, for its 5. Inhalation of airborne eggs (Cat or mouse survival and usually at the expense of the host. feces; perianal) 6. Sexual intercourse PARASITES Endoparasite - living inside the body of a host SIMPLE OR COMPLICATED ○ (Presence inside the host - INFECTION) Perpetuation of a species of parasite depends Ectoparasite - living outside the body of a host upon the ability to ensure transmission from ○ (Presence outside the host - one host to another INFESTATION) arrow ex. Kuto The parasite must adapt to protect itself from Obligate Parasites - host is needed at some the host’s defenses and external environment stage of their life cycle to complete their The parasite must overcome the attrition in the development and to propagate their species species by producing numerous progeny Facultative Parasites - may exist in a free-living state or may become parasitic when MEDICAL PARASITOLOGY TERMINOLOGIES the need arises. Accidental Parasites or Incidental Parasites - Effects of the parasite on the host establishes itself in a host where it does not Symptoms of infection may depend on the normally live. number of worms present, the nutritional Spurious Parasite - free living organisms that status of the host, or both passes through the digestive tract without Immune system of the hst may also be infecting the host. affected HOSTS Effects of host on the parasite 1. Definitive or Final host - one in which the Genetic constitution of the host influences the parasites attain sexual maturity host-parasite relationship  Diet or nutritional status of the host Effects on the immune mechanisms of the host CD4 cells - lower = more susceptible to infection Life Cycle: Infective and Diagnostic Stages, Mode of Transmission many parasites have a single host being transferred to another of the same species either through direct physical contact or by means of resistant or semi-resistant forms that are able to survive a period outside or away from the host Encysting protozoans: infective stage is called the - cyst Simple- Circle lang Non-encysting protozoans: infective stage is called - trophozoite Epidemiology - is the body of knowledge that concerns Egg-laying nematodes: infective stage is called with occurrence and distribution of disease in human - embryonated egg population and communities Even though treatment, prevention, and control Vector Transmitted Parasites measures are available, parasitic infection still A vector may also be a host if development of occurs and thus it is important to study and the parasite takes place within its body monitor their trends If the arthropod is simply an instrument of Prevalence - is a statistical study referring to the passive transfer, we refer to it as mechanical number of cases of a disease t hat are present in a vector (If a fly, feeding on fecal matter particular population at a given time containing cysts of E. histolytica, becomes Incidence - refers to the number of new cases that contaminated with some of these cysts, which develop in a given period of time it then transfers to food, it is acting as a mechanical vector of the amoeda) Distribution of disease (Belizario and De Leon, 2015) When an anopheline mosquito sucks blood 1. Endemic - When a disease in human from a malaria patient, the parasites must population maintains a relatively steady, develop in the mosquito before it is able to moderate level transmit the infection. In this instance the 2. Epidemic - If there is a sharp rise in the mosquito is both acting as a host and biologic incidence or an outbreak of considerable vector) intensity occurs a. Ex. Covid in Wuhan Life Cycle 3. Hyperendemic - If the prevalence of a disease - Refers to the development of a parasite in its in a community is high earliest form and its survival and development 4. Sporadic - If it appears only occasionally in in the outside environment and within the host one or at most few members of the community - The life cycle of parasite may be simple or 5. Pandemic - the disease covers extensive area complex. of the world - Complex life cycle involves two or more hosts. Control, Prevention, and Treatment Preventive and control measures may be taken against every parasite that is infective to human. These are designed to break the  transmission cycle, therefore crucial for If the experts can control a disease to the point successful parasite eradication. of no further transmission in the area, it is Preventing the infections to happen is to eliminated. After several years of elimination, intervene in the life cycle of the parasite and countries would likely contact the WHO for prevent the successful entry of the infective certification. stage to the host Parasitic treatment options include the INTRODUCTION TO ZOONOTIC PARASITES following: 1. Antiparasitic medication - Approximately 60% of all human pathogens are 2. Therapies option (change in diet, zoonotic vitamin supplements, fluid - 75% of emerging infectious diseases have an replacement, blood transfusion, bed animal origin rest) - Growing need for veterinarians and physicians to work together Elimination vs. Eradication Elimination ○ If a disease is eliminated, its transmission is no longer active in a certain area, such as a country. ○ If asked, the WHO can make an official ruling on whether a nation is free of the disease. A country wishing to get this recognition must voluntarily request it through a formal submission process. After a request, it is up to the WHO director-general to make the final ruling. They grant certification of elimination if a nation proves beyond reasonable doubt that their interruption of disease transmission has lasted for at least three consecutive years. Fungal Infections Eradication Animals such as cats and dogs passed to ○ If a disease is eradicated, worldwide humans transmission of it is over with no remaining cases. This renders further Viirus intervention measures unnecessary Covid-19 So far we have only achieved eradication with Many methods of parasite transmission to people smallpox. The WHO announced an end to smallpox involve animals (ex. cats, dogs, horses) infection in 1980. The CDC marked the event as "the - Bear with tapeworm: from raw fish biggest achievement in international public health." - Acatina folica - Stomachworm How are Diseases Eliminated and Eradicated? - Fleas and Ticks Disease control in a local setting is generally the first step. This means that experts use Vector-borne Parasites deliberate and continued efforts to lower the A vector is an agent which transfers a parasite rates of new infections, deaths and current from one host to another infections in one region. This area could be a Typical parasite vectors: mosquitoes, ticks, town, state or even country. fleas, mites, flies, and other insects  People become infected when a vector picks up Unlike Babesia and Chagas Disease, the parasite from an infected animal and Leishmania live in tissue and not the infects a human blood Spread through the bite of an infected Parasites carries by Vectors sandfly Many parasites that are carried by vectors are often found in the blood of humans and animals Trypanosoma cruzi Causes Chagas disease Damage to heart, digestive tract, and brain (in children) Spread by the "Kissing Bug, "native to South America and the Southern US The bug bites the human then defecates next to the wound. Rubbing bite wound spreads parasite into the wound. Parasite can cycle from animals like armadillos, raccoons, opossums, and foxes to bugs to humans. Waterborne Parasites Spread when humans come into contact with water that has been contaminated by an infected animal Common waterborne parasites include Giardia Cryptosporidium GIARDIA & CRYPTOSPORIDIUM Babesia Intracellular protozoa found in red blood cells Spread by infected ticks DID YOU KNOW? A&M University College of Veterinary Medicine started to stop the spread of the Cattle Fever Tick. GIARDIA & CRYPTOSPORIDIUM The causative agent was a species of Babesia ○ Obtain from swallowing water that the ticks were spreading to Texas cattle. contaminated by another infected human or animal Leishmania ○ Giardia is the 2nd most common parasitic disease in humans  ○ Cryptosporidium is the most common Or by putting toys in their mouth which have cause of diarrhea from swimming been on the ground ○ Both can cause severe diarrhea Hookworms HOW DO PEOPLE GET PARASITES Can penetrate the skin and gain entry into the From people or animals human body Bare feet are a common route of entry Methods of Parasite Transmission Wearing shoes is one of the best ways to Insect bites prevent paraistes from entering your feet Animal feces Handling raw meat and fish Hydatid Disease Handling cat litter boxes After humans consume the eggs passed by Contaminated fruits and vegetables dogs the worms can form huge cysts in the Infected food handlers body Contaminated water Don’t pop it because it will spread Contact with an infected person Broad Categories of Transmission Vectorborne (insects) Waterborne Fecal Oral Transmission ○ Most common way people become infected with zoonotic parasites ○ Parasites are spread to humans when they ingest the eggs from the feces of an infected animal Toxoplasmosis ○ Parasites spread by fecal oral How many of you have heard that pregnant ○ transmission generally live in the women shouldn't clean cat litter boxes? intestinal tràct That is because of the potential for them to Contaminated Meat contract toxoplasmosis which can cause them to lose their unborn child or can cause Hookworms and Roundworms congenital anomalies (ex. in the retina) Even though it is commonly associated with pregnancy and litter boxes, toxoplasmosis is more commonly transmitted through undercooked meat According to the CDC toxoplasmosis is the 3rd leading cause of foodborne related deaths in the US Carried by dogs and cats Kids often get infected from playing in sand boxes which animals have defecated  Gnathostomosis Meat can be contaminated with harmful bacteria and can also contain parasitic cysts which may infect people. Common parasites found in meat ○ Toxoplasma Contaminated Meat ○ Trichinella Meat can be contaminated with harmful ○ Taenia bacteria and can also contain parasitic cysts Summary which may infect people. Zoonotic parasites have many routes of Common parasites found in meat transmission to people ○ Toxoplasma ○ Vectors ○ Trichinella ○ Water ○ Taenia ○ Fecal Contamination ○ Gnathostoma ○ Infected Meat Trichinosis & Taeniasis Preventing Zoonotic Parasites Both caused by eating cysts in undercooked Brainstorm some ways we can prevent them… pork or beef ○ Always wash your hands Incidence rate has decreased with better ○ Keep sandboxes covered animal management and slaughter protocol ○ Wear shoes Fully cook your meat! (Ex. Samgyupsal) ○ Pick up animal feces when possible ○ Don't drink untreated water Cysticercosis ○ Cook meat thoroughly If a person consumes Taenia eggs they can develop cysts in their brain Interference  No host other than humans is implicated in the life cycle PROTOZOAN INFECTIONS Seven species of amoebae commonly found in human fecal specimens: 1. Entamoeba histolytica 2. Entamoeba dispar 3. Entamoeba hartmanni 4. Entamoeba coli 5. Entamoeba polecki 6. Endolimax nana lodomoeba butschlii Differentiated based on the basis of structure and size ENTAMOEBA Entamoeba histolytica Classified within Subphylum Sarcodina, Class LIFE CYCLE OF CYSTS AND TROPHOZOITES Lobosea, Order Amoebida pseudopod-forming non-flagellated protozoan parasite ○ No flagella Most invasive of the parasites in the Entamoeba family causing colitis and liver abscess ○ Colitis - inflammation of colon Life cycle consists of two stages: 1. infective cyst 2. invasive trophozoite  depends on integrated and community based efforts to improve environmental sanitation to provide for sanitary disposal of human feces Safe drinking water Safe food FREE-LIVING PATHOGENIC AMOEBAE exist as frav-living organisms in nature and only occasionally invade a host and live as parasites within host tissue free-living amoeba characterized by an active trophozoite stage and a dormant cyst stage Organisms reproduce by binary fission and encyst if the environment is unfavorable Ubiquitous organism isolated from air, aquaria, bottled mineral water, soil, swimming pools, deep well water, contact lens cleaning solutions LIFE CYCLE OF AMOEBA Causative agent of granulomatous amebic encephalitis (GAE) and Acanthamoeba keratitis LIFE CYCLE OF ACANTHAMOEBA PREVENTION AND CONTROL OF AMEBIASIS Granulomatous Amebic Encephalitis (GAE) GIARDIA Parasitic Flagellate Giardia lamblia - Giardiasis ○ 2 nuclei looks like the eyes ○ An intestinal parasitic flagellate of Acanthamoeba keratitis worldwide distribution ○ Known to cause epidemic and endemic diarrhea NAEGLERIA ○ The disease caused by this parasite is called giardiasis or lambliasis which Naegleria spp. (Free living pathogenic manifests as a significant but not amoebae) life-threatening gastrointestinal ○ free-living amebo-flagellate disease ameba - trophozoite form ○ Lives in the duodenum, jejunum and flagellate - swimming form upper ileum of human ○ causes human diseases ranging from ○ Has a simple asexual life cycle that gastritis and diarrhea to a rapidly fatal includes binucleated flagellated primary amebic meningoencephalitis trophozoites and quadrinucleated (PAM) infective cyst stages ○ acquired through oral and intranasal routes while swimming in contaminated pools, lakes and rivers can survive in elevated temperatures of up to 46°  PLASMODIUM MALARIA remains the leading parasitic disease that causes mortality worldwide Plasmodium carried by the (female) Anopheles mosquito (Anopheles minimus flavirostris) ○ P. falciparum - most virulent and prevalent. ○ P. vivax - prediwhat to young RBCs along TRICHOMONAS with P. ovale ○ P. ovale Trichomonas vaginalis ○ P. malariae - old RBCs ○ Trichomoniasis is caused by a one-celled protozoan organism called SYMPTOMS Trichomonas vaginalis. MAJOR ○ Unarousable coma MOST COMMON SYMPTOMS AMONG WOMEN: ○ Acidemia/acidosis ○ Vaginal discharge (color white, gray, ○ Severe normochromic normocytic yellow, green), usually frothy with anemia - no hemoglobin = no oxygen unpleasant smell ○ Renal failure - blockage in capillaries = ○ Vaginal spotting or bleeding black urine ○ Genital burning or itching ○ Pulmonary edema/ARDS - water in ○ Genital redness or swelling lungs/pressure or blockage in the ○ Frequent urge to urinate pulmonary arteries ○ Pain during urination or sexual ○ Hypoglycemia - glucose less than 40 intercourse mg/dl; liver is affected: risk MOST COMMON SYMPTOMS AMONG MEN: consumption in glucose (doble-doble) ○ Discharge from the urethra ○ Hypotension/shock ○ Burning during urination or after ○ Bleeding/ Disseminated intravascular ejaculation coagulation - lowers blood components ○ An urge to urinate frequently (wbc, rbc, etc.) ○ Convulsions - seizures when parasite goes into the brain MINOR ○ Hemoglobinuria - blood in the urine: black, brown, or red ○ Extreme weakness ○ Hyperparasitemia ○ Jaundice DIAGNOSIS Peripheral blood smear ○ Thick smear ○ Thin smear  Rapid diagnostic tests - detects if nag positive Gametocytes ingested by female Anopheles sa malaria differentiate into male and female gametes ELISA - screening - for blood donors which fuse to form a zygote and become TREATMENT sporozoites in the salivary gland Artemisinin-based combination therapy - first-line treatment; for pregnant patients; combined with primaquine Atovaquone-proguanil - second line treatment from other countries Chloroquine - main treatment for vivax ovale; for pregnant patients Amodiaquine - main treatment for vivax ovale Primaquine Quinine Artesunate - first line treatment for severe malaria with major symptoms MILLENIUM DEVELOPMENT GOALS: 8 GOALS FOR 2015 - Exo-erythrocytic cycle: outside the organ 1. Eradicate extreme poverty and hunger - Complex life cycle: 3 2. Achieve universal primary education 3. Promote gender equality and women empowerment 4. Reduce child mortality 5. Improve maternal health 6. Combat HIV/AIDS, malaria, and other diseases 7. Ensure environmental sustainability 8. Develop a global partnership for development Source: United Nations, General Assembly 2001 PLASMODIUM LIFE CYCLE 9 Anopheles mosquito feeds on blood & serves as the vector MALARIA Sporozoites enter bloodstream and proceed to Chills, fever, sweating-peak every 48hrs the liver within 30 minutes to infect Weakness, anemia, splenomegaly hepatocytes ○ High fever (up to 105 degrees Fahrenheit) with shaking chills ○ Profuse sweating when the fever 1 week = multiplication & transformation in suddenly drops the liver leads to theres PER HEPATO infected ○ Fatigue with only one sporozoite ○ Headache Merozoites infect red blood cells, initiating the ○ Muscle aches symptoms and pathology of malaria. ○ Abdominal discomfort Merozoites replicate and differentiate again ○ Nausea, vomiting Cell ruptures to release new merozoites (which ○ Feeling faint when you stand up or sit will infect more red blood cells) up quickly Some merozoites differentiate into Blocked capillaries - intense headaches, renal gametocytes: failure, heart failure or cerebral damage ○ Male (microgametocytes) ○ Female (macrogametocytes) TRYPANOSOMA AFRICAN SLEEPING SICKNESS Trypanosoma ○ Flagellated protozoans -2 species ○ tsetse fly (Glossina spp.) as carrier trypomastigote Multiplies in blood ○ Progresses to neurological stage, infects central nervous system → meningoencephalitis ○ Loss of consciousness. Hence, the SLEEP part. LEISHMANIA Leishmania ○ Caused by diploid protozoa belonging to genus ○ Vector: sandfly (Phlebotomus and Lutzomyia) ○ Produce amastigotes (ovoid or round bodies) intracellularly in mammalian host and promastigotes (w/ single flagellum) in the hindgut, midgut, and proboscis of insect vectors - Gambiense - east - Rhodesiense - west - Cutaneous Leishmaniasis - Highly endemic in middle eastern areas and South America PATHOGENESIS AND CLINICAL MANIFESTATIONS FOUR CATEGORIES:  1. Cutaneous leishmaniasis - most common; Formalin ether/ethyl acetate sore, ulcer concentration technique (FECT) 2. Diffuse cutaneous leishmaniasis-numerous Kinyoun's modified acid-fast stain diffuse satellite lesions; non-ulcerating 2. Indirect fluorescent antibody, enzyme 3. Mucocutaneous leishmaniasis-involvement of immunoassay mucus membranes of the nasal and oral 3. DNA probes specific for Cryptosporidium hominis cavities resulting to destruction of nasal 4. Acid-fast staining - also used in septum mycobacterium tuberculosis 4. Visceral leishmaniasis-spread of parasites into the bone marrow, spleen and liver COCCIDIANS Spore-forming, single-celled obligate intracellular protozoan Members of Phylum Apicomplexa are provided with cluster of secretory organelles (rhoptries, micronemes, polar rings w/ microtubules, conoid) which allows the parasite to enter the host cell Coccidians infect the intestinal tract of invertebrates and vertebrates including humans Coccidian life cycle includes an alternation of sexual and asexual multiplication ○ 3 sequential stages: 1. sexual cycle or sporogony → oocysts PATHOGENESIS AND CLINICAL MANIFESTATIONS 2. asexual cycle or schizogony/merogony Diarrhea lasting for 2 to 3 weeks → merozoites/meronts Abdominal pain, anorexia, fever, nausea, 3. gametogony → male (micro) and weight loss female (macro) gametocytes Villi of the intestines become blunted; (gamonts) infiltration of inflammatory cells into lamina propria and elongated crypts CRYPTOSPORIDIUM Varying degrees of malabsorption; excessive fluid loss CRYPTOSPORIDIUM ○ All stages of development are TOXOPLASMA completed in the gastrointestinal tract of the host. Toxoplasma gondii - coccidian that belongs to ○ Oocysts when passed out are already Phylum Apicomplexa infective. ○ Each oocyst contains four sporozoites, TOXOPLASMOSIS which are present at the time of ○ Parasitic with worldwide distribution; passage into the feces. infects humans and many species of ○ The oocyst is infectious and when animals ingested, the sporozoites attach to the ○ Infective stages: tachyoite, bradyzoite surface of epithelial cells of the Gl tract and oocyst ○ Life cycle: schizogony, gametogony and DIAGNOSIS sporogony in the intestinal epithelium 1. Stool examination - reveals the oocyst ○ Extraintestinal stages are asexual Sheather's sugar flotation stages: tachyoites and bradyzoites  ○ Definitive host: Cat (family Felidae) Toxoplasma lodging in the brain tissue SARCOCYSTIS SARCOCYSTIS SPP. Intracellular protozoa that infects humans and animals Causes sarcosporidiosis or sarcocystosis Zoites Banana-shaped cell with an apical complex Intermediate hosts are herbivores Definitive hosts are carnivores Sporocysts ○ 15-19um by 8-10pm ○ With 4 sporozoites ○ Can survive on external environment and infect IH PATHOGENESIS AND CLINICAL MANIFESTATIONS Commonly asymptomatic as long as the immune system of the patient is functioning well Begin as unicellular bodies with single Cysts can be found in the brain, skeletal and metrocyte heart muscles, retina ○ Metrocytes will then accumulate due to Manifestations: encephalitis, myocarditis, repetitive asexual reproduction pneumonia, hepatitis, splenomegaly, stillbirth When sarcocyst matures and abortion ○ Noninfectious metrocytes will give rise to infectious bradyzoites ○ After 2.5 months of infection, sarcocysts will mature and are ready to infect the DH  Intracellular protozoa reported to infect Bronchospasm humans and animals worldwide Pruritic rashes: itchy Infection is known as sarcosporidiosis or Lymphadenopathy: swelling of lymph nodes sarcocystosis Subcutaneous nodules with concurrent Simplest form: ZOITE - banana-shaped cell w/ eosinophilia pointed anterior end (apical Increased erythrocyte sedimentation rate: lab complex-micronemes, micropores, rhoptries) diagnostic test for ongoing inflammation Apical complex - believed to be associated with Increased creatinine level: kidney host cell penetration PATHOGENESIS AND CLINICAL MANIFESTATIONS Invasive form ○ vasculitis and myositis; may involve a wide variety of tissues including lymph nodes, muscles and the larynx Intestinal form ○ nausea, abdominal pain, diarrhea Other symptoms ○ anorexia, nausea, abdominal pain, diarrhea, vomiting, tachycardia DIAGNOSTIC Fecalysis TREATMENT Humans ○ No proven effective treatment ○ Trial of Cotrimoxazole and Corticosteroids Calves ○ Amprolium ○ Salinomycin PREVENTION In dogs, sarcocystis is non-infectious after cooking meat for 60,70 and 100C Freezing at 4 to -20C will render the bradyzoites in pork as noninfectious Avoid giving contaminated water, feeding and PATHOGENESIS bedding. 2 types of sarcocystosis ○ Rare invasive form BABESIA Vasculitis and myositis ○ Intestinal form BABESIA SPP. Nausea Tick Diarrhea Causes babesiosis Abdominal pain Infects humans, domestic and wild animals Exhibits host specificity SIGNS AND SYMPTOMS A hemosporidian parasite that causes Acute fever babesiosis, a hemolytic disease Myalgia Definitive/Primary Hosts: mammals  Intermediate hosts/vectors: ticks bursa, Rh. Life Cycle: 3 stages: sanguineus, Rh. 1. mammalian host-merogony in RBC evertsi, Rh. 2. tick vector-gamogony in gut and turanicus epithelium 3. sporogony accompanied with multiple B. trautmanni pig B. decoloratus, Rh. bursa, Rh. fission in various cells and organs turanicus, Rh. forming sparkinete and infective sanguineus, D. sporozoites reticulatus Vector ○ Ticks B. canis dog D. marginatus, D. Rhipicephalus spp. reticulatus, D. venustus, H. Dermacentor spp. leachi, H. Boophilus spp. plubeum, Rh, Ixodes spp. sanguineus Haemaphysalis spp. ○ Transmission within the vector B. gibsoni dog Rh. sanguineus, Transstadial H. bispinosa Transovarial B. vogeli dog Rh. sanguineus ○ 120 days B. microti human I. scapularis B. bigenia Cattle, bovine, water buffalo, zebu, white- tailed deer B. bovis Cattle, deer, stag B. divergens cattle B. argentina cattle B. microplus B. major cattle B. calcaratus, H. puntata Babesia Host Tick Vector species B. berbera cattle I. ricinus, I. persulcatus, B. B. ovis sheep and goat Rh. bursa calcaratus, Rh. bursa B. caballi horse, donkey, D. marginatus, D. mule reticulatus, D. B. matasi cattle D. silvarum, H. silvarum, D. punctata, Rh. nitens, H. bursa excavatum, H. dromedarii, H. suspense, Rh. 3 DEVELOPMENTAL PHASES bursa, Rh. Meregony sanguineus Gamogony B. equi horse, donkey D. marginatus, D. Sporogony mule reticulatus, H. excavatum, H. dromedarii, H. plumbeum, Rh.  LIVER FLUKES mature in the liver FASCIOLA Fasciola spp. Large digenetic trematodes found in liver and biliary passages of humans and ruminants Fasciola hepatica ○ Temperate liver fluke Fasciola gigantica ○ Tropical liver fluke Metacercaria exists in duodenum or jejunum ○ Release juvenile fluke that will penetrate the intestinal wall until it reaches the peritoneal cavity ○ Wander until it reaches the capsule of Glisson and enter the liver SIGNS AND SYMPTOMS Unembryonated eggs are carried by the bile Could be asymptomatic through sphincter of Oddi into the intestine Fatigue Eggs wild mature in the water in 9-15 days and Weight loss transform into miracidium once it exits the Malaise operculum Anorexia Miracidium will look for its first IH Intermittent fever ○ Snail from family Lymnaeidae Chills Lymnaea philippinensis Myalgia: muscle pain Lymnaea auricularia rubiginosa Arthralgia: joint pain Nausea SNAIL Emotional lability Miracidium turns into sporocyst then 1-2 Depression generations of redia before producing cercariae Hyperesthesia Cercariae will leave in 5-6 weeks at night ○ Attach itself to aquatic plants to become SEVERE CASES metacercariae ○ Hemolytic anemia Aquatic plants now serve as the ○ Hemoglobinuria: blood in urine 2nd IH ○ Jaundice Ipomea obscura ○ Pulmonary edema Nasturtium officinale FATAL OUTCOME ○ Elderly ○ Splenectomized individuals ○ Immunocompromised individuals ○ Individuals manifesting evidence of Lyme disease PARASITIC PLATYHELMINTHES  Dyspepsia Fever RUQ abdominal pain Sudden onset of fever Hepatomegaly Marked eosinophilia ○ Chronic stage Asymptomatic Worm obstruction may stimulate inflammation of biliary epithelium which may cause fibrosis Atrophy of liver parenchyma and periductal cirrhosis due to heavy infection Obstructive jaundice FASCIOLA HEPATICA Hemobilia Large, broad, flat body Biliary cirrhosis 18-51mm × 4-13mm Acute pancreatitis Suckers ○ Small and close to each other Ectopic sites of parasite migration Testes ○ Lungs ○ Highly branched ○ Subcutaneous tissue Ovary ○ Brain ○ Above testis ○ Orbit Uterus Unusual form of fascioliasis ○ Coiled and short ○ Ingestion of raw Fasciola-infected liver Egg ○ Worm will attach to the posterior ○ Large, ovoidal, and operculated pharynx ○ Yellowish to brownish in color Causes hemorrhagic ○ 140-180m x 63-90um nasopharyngitis and dysphagia FASCIOLA GIGANTICA Also known as halzoun 25-75mm × 3-12mm (Lebanon) and marrara (Sudan) Less developed shoulders Shorter cephalic cone DIAGNOSIS Intestinal ceca are more branched 1. Direct detection of Fasciola Eggs Ovary 2. Complete Blood Count ○ Longer and numerous 3. Abdominal Imaging (Ultrasound/CT Testes Scan/MRI/ERCP) ○ Farther from the posterior border of the 4. Biopsy body Egg TREATMENT ○ Same description as that of F. hepatica 1. Triclabendazole ○ 160-190m × 70-90um 2. Nitazoxanide PATHOGENESIS PREVENTION AND CONTROL Human fascioliasis 1. Avoid food and water contamination ○ Acute stage 2. Do not eat raw watercress/ water plants Asymptomatic 3. Cook food thoroughly  CERCARIA CLONORCHIS Attach to epithelium of 2nd IH upon contact thru the suckers Clonorchis sinensis ○ Freshwater fish Located at the bile duct and gallbladder of ○ Under fish scale or in the muscle, humans and fish-eating mammals encyst to become metacercaria Mode of transmission ○ Ingestion of metacercaria present in infected raw or undercooked fish C. sinensis metacercaria will excyst in the duodenum Young flukes proceed to ampulla of Vater to the common bile duct and to distal biliary capillaries to transform into adult worms Adult worms attach to bile duct mucosa by their suckers ○ Embed itself without forming a permanent epithelial lining ulcer 10-25mm x 3-5mm Eggs move to the intestine together with the Presence of transparent tegument bile then wait to be excreted out of the body Vitellaria ○ At the level of uterus Testes ○ 2 large highly branched structures at the posterior half of the body MIRACIDIUM Hatch after egg is ingested by 1st IH ○ Parafossarulus spp. ○ Bulinus spp. ○ Semisulcospira spp. ○ Alocinma spp. ○ Thiara spp, ○ Melanoides spp. INSIDE THE SNAIL Egg Miracidium turns into sporocyst then into ○ Yellowish brown and ovoid redia ○ 26-30pm x 15-17m ○ Redia will produce cercaria then ○ With small protuberance at the release to the water abopercular end PATHOGENESIS Phases ○ Desquamation of epithelial cells ○ Hyperplasia and desquamation of epithelial cells Hyperplasia, desquamation of epithelial cells, and DIAGNOSIS adenomatous tissue formation 1. Microscopic Identification of Egg in stool ○ Marked proliferation of periductal 2. Abdominal Imaging connective tissue with scattered abortive acini of epithelial cells, and TREATMENT fibrosis of the biliary duct's wall 1. Albendazole Light infection 2. Praziquantel ○ Asymptomatic ○ Nonspecific clinical signs PREVENTION AND CONTROL ○ Diarrhea Cooking ○ Abdominal pain ○ Cook fish adequately (to an internal Moderate infection temperature of at least 145° F [-63° C]). ○ Fever Freezing (Fish) ○ Diarrhea ○ At -4°F (-20°C) or below for at least 7 ○ Inappetence days (total time); or ○ At -31 F (-35°C) or below until solid, and ○ Rash storing at -31 F (-35°C) or below for at ○ Edema least 15 hours; or ○ Night blindness ○ At -31°F (-35°C) or below until solid and ○ Swollen abdomen storing at -4°F (-20°C) or below for at ○ hepatomegaly least 24 hours. Heavy infection ○ Acute pain in RUQ TREMATODA Chronic stages ○ All digenea are parasitic ○ Liver malfunction ○ Dorsoventrally flactened worms ○ More severe late complications without any segmentation ○ Calculi ○ No coelom ○ Acute suppurative cholangitis ○ No blood vessels but with simple ○ Recurrent pyogenic cholangitis ladder nervous system ○ Cholecystitis ○ Possess 2 suckers used to attach to ○ Hepatitis their hosts ○ Pancreatitis Oral sucker has the mouth ○ Pharynx Muscular  To pump food into the blind ○ Penetration glands secrete proteases ending gut and other lytic enzymes upon contact ○ Most are hermaphrodites with appropriate host ○ Excretory system ○ Miracidia with land snails as IH will Simple protonephridial system hatch upon ingestion by the snail and Protonephridium penetrate the gut epithelium Flame cell and tubule cell SPOROCYST ○ Excreta are collected from ○ This stage has most organ systems protonephridia through small ducts reduced to the bafe minimum and acts which merge to a central dict that as a germinal sac opens into the excretion pores ○ Takes up nutrients only over its ○ Reproductive systems take up a large tegument portion of the parasite's body ○ Germinal mass expands and develops ○ To enhance the chances to complete into daughter sporocysts, redia or the complex life cycle, they produce cercaria massive numbers of offsprings ○ Asexual reproduction REDIA Occurs in germinal balls ○ Redia has features of the adult fluke Where omnipotent ○ Mobile in the snail progenitor cells are ○ Can prey on sporocysts and redia of the located same or other species Can initiate embryo development without CERCARIA fertilization ○ Stage that leave the IH and infect the All species have at least 2 DH hosts ○ There can be many consecutive waves One of which is snail of "shedding" from the snail Not all stages are found in the ○ Already show many anatomical life cycle of all species features of the adult fluke Miracidia and cercariae Reflecting the ecology of their hosts, cercaria Infective stages have developed an array of adaptations to EGG achieve successful infection ○ Contains embryo rather than an oocyte ○ Direct penetration of host skin upon ○ Shed at different degrees of maturity water contact by different flukes Schistosoma spp ○ Need to leave the DH's body to continue ○ Encystation within the muscle of the its development intermediate host ○ Mature miracidium within the egg Metacercariae of Clonorchis uses light, osmolarity, and temperature spp. in fishes as clues to when hatching is ○ Encystation on plants appropriate Fasciola spp. ○ Hatching proceeds in most species Single-tailed cercariae through a preformed "door" Source: lymnaeid snails MIRACIDIUM LUNG FLUKES ○ Highly motile due to cilia - microtubules ○ With simple eyes and several chemical PARAGONIMUS and mechanical receptors PARAGONIMUS SPP.  ○ Paragonimus westermani ○ Adult worm resides in the lungs, Found in Asia and Oceania encapsulated in pairs by layers of P. skrjabini, P. granuloma miyazaka, P. ○ Eggs are trapped most of the time in heterotremus the surrounding tissues and cannot Most widely prevalent species leave the lungs First describe in 2 Bengal If they escaped, pass through tigers in Europe in 1878 air passages, move up and out *table by ciliary epithelium In the pharynx, they are Adult swallowed and passed through ○ 7.5-12mm x 4-6mm alimentary canal then out of ○ Very thick: 3.5-5mm in dersoventral the feces axis Larvae within the ova ○ Reddish brown in color ○ 16 days to several weeks in Resembles coffee beans water before develop into ○ Tegument miracidia Covered with scalelike spines ○ Oral and ventral suckers almost the Miracidia same in size ○ Needs a freshwater snail IH ○ Excretory bladder Antemelania spp. From near the pharynx to the ○ Will form sporocysts then rediae then posterior end of the body cercariae inside the snail Testes Cercariae. ○ Lobated ○ Enter second IH Ovary Sundathelphusa philippina ○ Lobated ○ Turn into metacercariae ○ Found below ventral sucker to the left DH eats mountain crab Uterus ○ Worm excyst in duodenum ○ Tightly coiled into rosette ○ Juveniles penetrate intestine and ○ Found at the right of ventral sucker embed in abdominal wall Vitelline follicles ○ Reenter coelom and penetrate ○ Extensive in lateral of the body diaphragm and pleura ○ Runs from pharynx level to the ○ Penetrate lung and form a cyst posterior end together ○ Mature in 8-12 weeks Eggs ○ ovoid ○ With operculum PATHOGENESIS ○ 80 - 1  The larvae migrate for approximately 1 week May cause congestion, penetrate the diaphragm, enter the pleural vasculitis, and capillary cavity, and migrate directly through lung rupture tissue to reach the bronchi. ○ Chronic stage Form cystic cavities and develop into adult Cortical or subcortical atrophy worms in 5-6 weeks. and secondary ventricular Adult worms induce an inflammatory dilatation granulomatous response in the lungs Cerebral paragonimiasis generating a fibrous cyst that contains ○ Headache ○ purulent, bloody effusion which eggs ○ Meningismus are passed into the environment via ○ Seizures expectoration ○ Hemiparesis ○ eggs released by the flukes in the ○ Blurring of vision sputum which may be swallowed and ○ Diplopia passed with feces. ○ Homonymous hemianopsia: one side’s If deposited in fresh water. eggs hatch to vision is black/half release miracidiae, which then invade specific ○ Aphasia: garbled/slurred speech; snail hosts. difficulty comprehending These cercariae are released from the infected snail COMPLICATIONS They encyst (as metacercariae) in the gills, A serious consequence of paragonimiasis may muscles, legs, and viscera of freshwater lead to crustaceans. ○ chronic bronchiectasis ○ pleural fibrosis SIGNS AND SYMPMTOMS Bronchiectasis Early stages are asymptomatic ○ is a chronic condition where the walls Chronic cough - most common of the bronchi are thickened from Hemoptysis - most common; coughing of inflammation and infection blood Chest pain DIAGNOSIS Dyspnea: difficulty breathing Identification of Paragonimus eggs in sputum Low-grade fever Stool samples Fatigue Tissue biopsy Generalized myalgia: muscle pain everywhere Serologic Test (P.westermanii) Chronic bronchiectasis: damaged/honeycomb TREATMENT lungs: severe symptom Praziquantel ○ patients are candidates for lung ○ 25mg/kg given orally three times a day transplant for 2 consecutive days Pleural fibrosis: walls of bronchi harden For cerebral disease because of infection; cannot expand well ○ Corticosteroids - help in reducing inflammation response around the MANIFESTATION dying flukes Cutaneous paragonimiasis ○ Praziquantel at 25mg/kg given orally ○ Slow-moving nodular lesion in three times a day for 2 consecutive abdomen or chest days Cerebral paragonimiasis Alternative: ○ Most serious complication ○ Triclabendazole ○ Juvenile P. westermani migrates from 2 doses of 10 mg/kg given 12 pleural cavity to cranial cavity through hours apart in patients 6 years soft tissues along internal jugular vein of age and older. PREVENTION AND CONTROL Do not eat RAW freshwater crabs or crayfish Cook crabs and crayfish for at least >63C For travelers, avoid traditional meals containing undercooked freshwater crustaceans BLOOD FLUKES SCHISTOSOMA Sporocyts will reproduce asexually and give rise to free-swimming cercariae in 60-70 days Cercariae will penetrate the DH's skin when Schistosoma spp. they come in contact in infested fresh water 5 species of medical importance ○ Will lose their tails ○ S. japonicum - lodge in superior ○ Transform to schistosomula mesenteric vein (SMV) ○ Enter superficial lymphatic vessels or ○ S. haematobium - urinary bladder; subcutaneous veins bladder carninoma ○ Enter the lungs ○ S. mansoni - large intestine; large Schistosomules differentiate into male and mesenteric veins female parasites ○ S. mekongi - intestines ○ Female larger than male ○ S. intercalatum Occupy gynecophoric canal of male Deposit 500-2,000 immature eggs per day in branches of portal vein Eggs will mature and embryonate in 10-12 days ○ Be deposited in mucosal or submucosal terminal veins or capillaries ○ Escape through ulcerations to intestinal lumen ○ Excreted through feces ○ Will hatch only in clean fresh water with sufficient oxygen Must reach the portal vein SCHISTOSOMA JAPONICUM (REPRESENTATIVE SPECIES) Embryonated egg from the definitive host's stool will hatch into free-swimming miracidia in 2-4 hours in the water ○ Definitive hosts: humans; mammals Miracidia infects snail IH and develop into sporocysts ○ Oncomelania hupensis quadrasi - usually found in freshwater  ○ Apical papilla Diagnostic stage: egg ○ Epidermal plates with cilia Infective stage: cercariae ○ Primitive gut ○ Pair of cephalic unicellular penetration glands ○ 2 pairs of flame cells ○ Germinal cells Phototactic - move directionally in response to a light source Egg ○ Ovoid, round, or pear-shaped ○ Pale yellow ○ 46-110m x 37-90um ○ Thin-shelled where residual tissue or RBC may be found ○ Curved hook or spine seen at one of the polar ends INTERMEDIATE HOSTS Biomphalaria sp. ○ S. mansoni Oncomelania hupensis quadrasi ○ S. japonicum Bulinus sp. ○ S. haematobium ○ s. Intercalatum ○ S. guineensis Neotricula aperta ○ S. mekongi Sporocyst ○ Miracidium develops into sporocyst few days after the miracidium penetrates into the soft parts of the snail and loses their cilia ○ Daughter sporocysts are formed on eighth day from the development of the first generation Miracidium ○ Morphological features  Migrate through loose connective tissue to reach the liver Cercaria ○ Emerge from sporocyst, leave the snail into the fresh water ○ with body and forked tail Main body measures 100-500mm x 40-60um Tail trunk measures 140-150um x 20-35um Forked part measures 50-70mm~ Cercaria In situ: Superior mesenteric vein (near jejunum) Adult fluke ○ Large sucker found at the anterior end ○ Ventral sucker PATHOGENESIS ○ Gonophore posterior to the ventral "Swimmer's itch" sucker ○ Cercarial penetration of skin with ○ Male dermatitis with pruritus 12-20mm x 0.4-0.5 m ○ Self-limiting With gynecophoric canal to hold the female Testes One row above ventral sucker ○ Female 15-26mm × 0.3mm Ovary Single, pyramidal shape in midline Schistosomule migration ○ Symptoms are caused by the body’s reaction to the eggs ○ May lead to CNS lesions ○ "Snail fever" or Katayama fever or Katayama syndrome Easy fatigability Respiratory symptoms Arthralgia Myalgia Eosinophilia Fever Malaise Hepatosplenomegaly  Hepatic dysfunction Death ○ Migration through pulmonary circulation Wheezing Coughing ○ Aberrant migration Occlude circulation in brain and spinal cord Seizure Paresthesia Transient ischemic attack Stroke ○ Chronic schitosomiasis Prolonged infection up to 10 years Liver cirrhosis - damaged liver Kidney damage Urinary bladder damage Hepatosplenomegaly Ascites - bloating due to water in peritoneal cavity; related to kidney and liver damage DIAGNOSIS Examination of stool and/or urine ○ Must take at least 3 samples in - Macular rash different days Review history of travel or residency history Serologic Test for Antischistosomal antibody ○ Collected at least 6 to 8 weeks after infection TREATMENT Praziquantel ○ drug of choice ○ For travelers, treatment should be at least 6-8 weeks after last exposure 3 stages of clinical course of schistosomiasis ○ a single course of treatment is usually infection curative ○ Incubation ○ repeat treatment may be needed after Period from cercarial 2 to 4 weeks penetration and schistosomular migration to the time the flukes mature ○ Period of early egg deposition and extrusion ○ Period of tissue proliferation  Embryophore PREVENTION AND CONTROL ○ Thick Avoid swimming or wading in freshwater ○ With several tiny pores Drink safe water. ○ The outer cellular covering of the Water used for bathing should be brought to a hexacanth embryo forms the inner part rolling boil for 1 minute. Water held in a storage of the eggshell tank for at least 1 - 2 days should be safe for ○ 31 to 43 um In diameter six-hooked bathing. oncosphere within. Vigorous towel drying after an accidental, very brief water exposure may help to prevent TAENIA SAGINATA parasites from penetrating the skin. Beef tapeworm Reducing the number of infections in people Inhabits upper jejunum and/or Can live as long as 25 years Eliminating the snails that are required to Adults maintain the parasite's life cycle. ○ 4-10m in length Improving sanitation could reduce or eliminate ○ 1,000-4,000 proglottids transmission of this disease. Mass drug treatment of entire communities Scolex and targeted treatment of school-age children ○ Cuboidal in shape ○ With 4 prominent acetabula TAPEWORMS ○ Devoid of hooks Mature proglottids TAENIA ○ Slightly wider than long Gravid proglottids ○ Longer than wide Taenia spp. A parasitic infection caused by the tapeworm Gravid proglottids passed out of the feces species: ○ Each proglottid can act as individual ○ Tania saginata: beef tapeworm (cow) worm ○ Tania solium: pork tapeworm (pigs) When proglottids start to dry up Can affect humans directly ○ Rupture happens within the midventral (can become host) body wall ○ Tania asiatica: Asian tapeworm Eggs will escape Infected host can become infected by; Larvae are infective to IH and remain viable for ○ Eating raw or undercooked beef/pork several weeks ○ Cattle To differentiate between T. saginata and T. ○ Llama solium: difference in sex cells ○ Goat ○ Sheep Giraffe EPIDEMIOLOGY ○ Reindeers T. saginata ○ Easter Europe, Russia, Easter Africa Inside Intermediate Host and Latin America ○ Eggs hatch in duodenum T. solium ○ Penetrate mucosa and enter intestinal ○ Under-developed communities venules ○ Latin America, Eastern Europe, ○ Carried throughout the body sub-Saharan Africa, India, and Asia ○ Exit capillaries between muscle cells T. asiatica Enter muscle fiber ○ Limited to Asia: Republic of Korea, ○ Develop into infective cysticerci in 2 China, Taiwan, Indonesia, and Thailand months ○ Metacestodes white, pearly, and up to 10 mm Eggs in diameter and contain a ○ Spherical in shape single, invaginated scolex. ○ With thin, hyaline, outer membrane Lost when egg is voided out If a person eats infected beef and cooks it insufficiently  ○ Juveniles won't get killed ○ Person becomes infected ○ Invaginated scolex and neck will evaginate in response to bile salts Bladder digested by the host or absorbed by the scolex Budding of proglottids begins Shedding of gravid proglottids within 2-12 weeks Strobila ○ Commonly 2-3m Mature proglottids ○ Wider than longer Gravid proglottids ○ Longer than wide TAENIA SOLIUM Aside from the ovaries, the number of testes also varies from both species. ○ 150-200 testes for T solum Taenia solium ○ 300-400 testes for T saginata ○ Pork tapeworm ○ Most dangerous adult tapeworm of humans Infection with eggs may cause cysticercosis ○ Humans can serve both the IH and DH ○ Humans can get infected through food contamination and/or fingers with eggs ○ Cats and dogs can also be IH Scolex ○ With typical, non-retractable taenid rostellum Armed with 2 circles of 22-32 hooks that measures 130-180um long ○ Spheroid in shape, smaller than that of t. Saginata  In gravid proglottids, you can differentiate T. The most visible symptom of taeniasis is the solium and T. saginata based on the numbers active passing of proglottids (tapeworm of the uterus segments) through the anus and in the feces. ○ T. saginata: 15-20 or 30 lateral branches In rare cases, affects the appendix, or the bile