Bio 520 Week2: Parasites for the Heart and Muscle for Exam 1

Taeniasis

*Taeniasis* in humans is a parasitic infection caused by the tapeworm species: -Taenia saginata (beef tapeworm), solium (pork tapeworm), asiatica (asian tapeworm) Humans can become infected with these tapeworms by eating raw or undercooked beef, or pork. people with *Taeniasis* may not know they have a tapeworm infection because symptoms are usually mild or nonexistent. Taenia solium tapeworm infections can lead to *Cysticercosis*, which is a disease that can cause organ and tissue damage

Roundworm Infection: Trichinosis

*Trichinosis, trichinellosis, or trichiniasis* is caused by roundworms of the genus Trichinella. Several supspecies cause human disease, but T. spiralis is most known. Infection may occur without symptoms, while intestinal invasion can cause diarrhea, abdominal pain, or vomiting Larval migration into muscle tissue (one week after being infected) can cause edema of the face or around eyes, conjunctivitis, fever, muscle pain, splinter hemorrhage, rash, and peripheral eosinophilia. Life-threatening cases can result in myocarditis, CNS disease, and pneumonitis. Larval encystment in the muscles causes pain and weakness, followed by slow progression of symptoms

Symptoms in Intermediate hosts: Humans with intramuscular sarcocystosis

-Intramuscular cysts are asymptomatic and no inflammatory response usually occurs -Only 8 cases have been reported with vasculitis and/or myositis -nodules may result

Chagas Disease

American Trypanosomiasis or Chagas disease is caused by haemoflagellated protozoan parasites that belong to the family of the Trypanosomatidae. Members are characterized by a *single large mitochondrion containing body - the kinetoplast* (that stains darkly in histological preparations)

Symptoms for Intermediate Hosts: Animals with intramuscular sarcocystosis

Body temperature elevates for a day approximately 2 weeks after ingestion of sporocysts Acute inflammatory reaction occurs about 4 weeks after ingestion -Characterized by massive perivascular infiltration of mononuclear cells and multi-organ petechial hemorrhage associated with: weakness, fever, abortion in pregnant animals, occasionally death Severity of infection is dependent on the number of sporocysts ingested Fail to fully recover from acute phase to chronic infection: inappetence, weight loss, loss of hair or wool, poor/stunted growth, muscle atrophy, lethargy, weakness Histological examination: widespread myositis, glossitis and inflammation of cardiac muscle

T. solium: Cysts in brain or spinal cord

Cause the most serious form of the disease called *neurocysticercosis* may cause no symptoms may cause seizures and/or headaches (more common) may also cause confusion, difficulty with balance, brain swelling, and excess fluid around the brain (less common) may cause stroke or death

Tripanosoma cruzi

Chagas Disease: American Trypanosomiasis

T. solium: Prevention

Cook: 140 for 5 minutes Freeze: -4 for 24 hours Hygeine: -wash hands with soap and warm water after using toilet, changing diapers, and before handling food -teach children the importance of washing hands -wash and peel raw vegetables and fruits before eating -use good food and water safety practices while traveling in developing countires -drink only bottled or boiled (1min) water or carbonated drinks in cans or bottles -filter unsafe water through an "absolute 1 micron or less" filter and dissolve iodine tablets in filtered water; "absolute 1 micron" filters found in camping and outdoor supply stores

T. solium: Disease

Cystcs called cysticerci, can develop in muscles, eyes, brain, and spinal cord. symptoms depend on location, size of cyst, number, and stage of cyst. Cysts in brain or spinal cord Cysts in the muscles

Diagnosis of Intramuscular Sarcocystosis: Animals

Detected in meat via direct observation of macroscopic sarcocysts or microscopic examination of histological sections

T. spiralis: Diagnosis

Diagnosis of trichinellosis is made in patients whose signs and symptoms are compatible, have positive lab test, and who can recall eating raw or undercooked pork or wild game meat. Laboratory diagnosis of Trichinella infection is most often made by a Trichinella antibody test. In some cases a muscle biopsy may be performed

T. spiralis: Prevention

Education: thoroughly cook meats like pork above 70C garbage scrapes fed to pigs should be sanitized

Sarcocystis spp.: Epidemiology: Humans

Few large-scale population surveys conducted Tropical or subtropical countries in Asia and Southeast Asia - of 46 cases reported by 1990, 11 from india, 13 from southeast asia Many infections go unreported -sarcosystis spp. have been found in muscle tissues in US during autopsies -more recently approximately 60 cases have been reported in US, incidentally

T. spiralis: Disease

First symptoms of trichinellosis are gastrointestinal, usually occuring 1-2 days after a person consumes raw or undercooked meat from a Trichinella-infected animal. Symptoms include; nausea, diarrhea, vomiting, abdominal pain The classic trichinellosis symptoms occur within 2 weeks after eating contaminated mean, and can last up to 8 weeks: muscle pain, fever, swelling of the face, particulary eyes, weakness or fatigue, headache, chills, itchy skin or rash, cough, diarrhea, constipation Symptoms range from mild to severe and relate to number of infectious worms consumed in meat. Many mild cases are never specifically diagnosed because they are assumed to be flu or other common illnesses. if infection is heavy, persons may have trouble coordinating movements, and have heart and breathing problems. although rare, death can occur in severe cases

Chronic Chagas Disease

Following the acute phase, most infected people enter into a prolonged asymptomatic form of disease (called *"chronic indeterminate"*) during which few or no parasites are found in the blood. During this time, most people are unaware of their infection. many people may remain asymptomatic for life and never develop Chagas-related symptoms. However, 20-30% of infected people will develop debilitating and sometimes life-threatening medical problems over teh course of their lives. Complications of chronic Chagas disease may include: heart rhythm abnormalities that can cause sudden death; a dilated heart that doesnt pump well; a dilated esophagus or colon, leading to difficulties with eating or passing stool In people who have suppressed immune systems, Chagas disease can reactivate with parasites found in the circulating blood. This occurrence can potentially cause severe disease.

Sarcocystis spp.: Epidemiology: Cattle

High percentage worldwide -likely 50% of adult swine, cattle, and sheep are infected -Japan, germany, brazil, india S. cruzi and S. hominis

Sarcocystis: Symptoms in Defenitive host

Humans: -Intestinal sarcocystosis: ingestion of raw meat: nausea, stomach ache, diarrhea, symptoms only persisted about 36 hours Animals: clinical signs rare

Pathology of Intramuscular Sarcocystosis

Humans: Intramuscular -rare invasive form -vasculitis and myositis Intestinal -nausea, abdominal pain, diarrhea

Sarcocystosis: Summary

If traveling, be conscious of undercooked meat and water in areas of poor sanitation Infection is not fatal for humans

Chagas Disease: Prevention

In endemic areas of Mexico, central and south america, improved housing and spraying insecticide inside housing to eliminate triatomine bugs has significantly decreased the spread of chagas disease. Further, screening of blood donations for chagas is another important public health tool in helping to prevent transfusion - acquired disease. Early detection and treatment of new cases, including congenital will help reduce burden of disease In the US and in other regions where Chagas is now found but not endemic, control strategies are focused on preventing transmission from blood transfusion, organ transplantation, and mother-to-baby

Chagas Disease: T. cruzi: Disease

In the human host, Chagas disease affects primarily the nervous system and heart. Chronic infections result in various neurological disorders, including dementia, megacolon, and mega-oesophagus, and damage to the heart muscle. Left untreated, the disease is often fatal

Sarcocystis spp.

Intracellular protozoan parasite infect reptiles, birds, and mammals obligate heteroxenous species: herbivorous intermediate host, carnivorous defenitive host First reported in 1843: described as white, threadlike cysts in striated muscles >100 species: -*intramuscular sarcocystosis* -intestinal sarcocystosis

T. solium: Diagnosis

MRI CT scan Ultrasound scan Serology

T. spiralis: males and females

Males of T. spiralis measure between 1.4 and 1.6 mm long and are more flat anteriorly than posteriorly. The anus can be found in the terminal (side) and they have a lare copulatory pseudobursa on each side Females of T. spiralis are about twice the size of the males and have an anus found terminally. The vulva is located near the esophagus. The single uterus of the female is filled with developing eggs in the posterior portion, while the anterior portion contained the fully developed juveniles.

T. spiralis: Treatment

Most cases go undetected Intradermal tests, flocculation, and agglutination tests can detect parasite that are at least 2-3 weeks old Agglutination - cells clump from allergic reaction Flocculation - clarifying agent causes parasite to clump

Roundworms

Nematodes or roundworms, are a group of invertebrates with long, round bodies. they rance is size from those that can ne seen by the naked eye to those several hundredths of an inch long that can only be seen under microscope Parasitic roundworms can live on or in humans where they can cause a variety of health problems. most parasitic roundworm eggs or larvae are found in the soil and enter the human body when a person picks them up on the hands and then transfers them to the mouth. the eggs or larvae also can enter the human body directly through the skin. with exception of the parasitic roundworm that causes *Trichinosis*, mature adult roundworms eventually end up or live in human intestines and cause infection and disease. In *trichinosis* , it is the movement of the larvae through the body from intestines and their encystment in muscle tissue that create serious problems

Treatment of Intramuscular Sarcocystosis

No treatment approved Need experiments to determine efficacy of... albendazole metronidazole cotrimoxazole

T. spiralis: Epidemiology

People acquire trichinellosis by consuming raw or undercooked meat infected with the Trichinella parasite, particularly wild game meat or pork. Even tasting very small amounts of undercooked meat during preparation or cooking puts you at risk for infection. Outbreaks occur in settings where multiple people consume the same Trichinella - infected meat Worldwide, an estimated 10,000 cases of trichinellosis occur every year.

Diagnosis of Intramuscular Sarcocystosis: Humans

Persistent myalgia, periodic weakness, subcutaneous nodules, dermatomyositis, eosinophilia, elevated creatnine kinase levels Travel to tropical locations Muscle biopsy specimens -sarcocysts identified by microscopic examination of histologic sections stained with hematoxylin and eosin, or PAS Reaction (Periodic acid Schiff: Carbohydrate in tissue section) -complete blood count to check for eosinophilia Sarcocysts of several unidentified species are still occasionally found in human muscles Many species are hard to distinguish from another - morphology of the wall varies with age of the sarcocyst, host cell, and methods of fixation

Sarcocystis: Classification

Phylum: Apicomplexa: possess a unique form of orgnaelle that comprises a type of plastid called an apicoplast, and an apical complex structure Class: Sporozoa: have no cilia or flagella Order: Eucoccidiorida: miscroscopic spore forming Family: Sarcocystidae Genus: Sarcosystis

Trichinosis: T. spiralis: Classification

Phylum: Nematoda: Roundworms, long thread-like, tube-like gut with mouth and anus Class: Phasmidea: have phasmids (a sensory organ at the tail region) Order: Trichurata Genus: Trichinella Species: spiralis

T. solium Classification

Phylum: Platyhelminthes: triploblastic, bilaterally symmetrical, acoelomate, no digestive tract, monoecious (has both male and female reproductive parts, hermaphrodite) Class: Cestoda: vertebrate GI parasite Order: Cyclophillidea: 4 suckers on its scolex Genus: Taenia : ribbon Specis: solium: throne

Chagas Disease: T. cruzi: Classification

Phylum: Sarcomastigophora: Unicellular or colonial, and may be autotrophic or heterotrophic Class: Zoomastigophorea: animal-like protozoa Order: Kinetoplastida: presence of kinetoplast Genus: Trypanosoma: bore tissue in another organism and feed on blood and lymph Species: cruzi

T. solium: Treatment

Praziquantel Albendazol Steroids Surgery

Trichinella spiralis

Round worms

Sarcocystis spp.

Sarcocystosis

Sarcocysts: Disease

Striated muscles: tongue, esophagus, diaphragm, cardiac muscle Occasionally, smooth muscle Measure about 10 by 15 um Contain 4 sporozoites and a discrete granular residual body

Parasites of the Heart and Muscles

Taenia solium Tichinella spiralis Tripanosoma cruzi Sarcocystis spp.

Cysticercosis

Taenia solium tapeworm infections can lead to cysticercosis, which is a disease that can cause organ and tissue damage, resulting in: fever cystic masses or lumps allergic reactions to the larvae bacterial infections neurological diseases including seizures

Tapeworm infection

Tapeworm infection is caused by ingesting food or water contaminated with tapeworm eggs or larvae. If you ingest tapeworm larvae, they develop into adult tapeworms in your intestines (intestinal infection). If you ingest certain tapeworm eggs, they can migrate outside your intestines and form larval cysts in body tissues and organs (invasive infection)

Sarcocystosis: Prevention

Thoroughly cook or freeze meat Sarcocysts prevented by killing bradyzoites in pig muscles -noninfectious after --cooked at 60C for 20 min, 70C for 15 min, and 100C for 5 min --freezing at -4 and -20 for 48 and 24 hours Boil contaminated water Feed supplies for livestock kept covered Dogs and cats (definitive host) kept out of livestock housing

Chagas Disease: Treatment

Treatment is recommended for all people diagnosed with acute infection, congential infection, and those with suppressed immune systems, and for all children with chronic infection. Adults with chronic may also benefit. For cardiac or gastrointestinal problems resulting from Chagas disease, symptomatic treatment may be helpful. Patients should consult with their primary health care provider. Some patients may be referred with their PCP. some patients may be referred to a specialist, such as cardiologist, gastroenterologist, or infectious disease specialist. In US, medication for Chagas is available only through CDC. PCP can talk with CDC staff about whether and how you should be treated.

Trichinosis: T. spiralis

Trichinella species are the smallest nematode parasite of humans, have an unusual lifecycle, and are one of the most widespread and clinically important parasites in tthe world. The small adult worms mature in the intestines of a definitive host (pig). each adult female produces batches of live larvae, which bore through the intestinal wall, enter the blood and lymphatic system, and are carried to striated muscle. Once in the muscle, they *encyst*, or become enclosed in a capsule. Humans can be infected by eating infected pork, horsemeat, or wild carnivores.

Chagas Disease: T. cruzi: Epidemiology

a few species of trypanosoma are also found in new world. T cruzi, causing chagas disease in latin america is only distantly related to the african trypanosomes. It is an intracellular parasite that is transmitted via blood-sucking bugs (*Triatoma*). Chagas disease is found throughout central and northern south america, central america, and mexico. Found in number of animals, humans, dogs, cats, rodents, and infection can be transmitted from these animals to humans.

Tapeworms

flat segmented worms that usually live in the intestines of animals. animals that have three stages of life, including egg stage, larvae stage, and adult stage when eggs are produced A fully matured tapewrm consists of a head (scolex), neck, body (strobilla), with chain of segments called proglottids

T. solium: Cysts in the muscles

generally do not cause symptoms may cause lumps under the skin, which can sometimes become tender

Chagas Disease: T. cruzi

named after Brazilian physician Carlos Chagas, who discovered the disease in 1909. caused by parasite Trypanosoma cruzi, which is transmitted to animals and people by insect vectors found only in americas (mainly rural areas in latin america, poverty). Also referred to as *American trypanosomiasis*

Acute Chagas Disease

occurs immediately after infection, may last up to a few weeks or months, and parasites may be found in circulating blood. Infection may be mild or asymptomatic. There may be fever or swelling around site of inoculation (where parasite entered into skin or mucous membrane). rarely acute infection may result in severe inflammation of heart muscle or brain and lining around the brain

Epidemiology

person with an adult tapeworm, living in gut, sheds eggs in stool. pig eats the eggs in the stool. the eggs develop into larvae inside pig and corm cysts (*cysticerci*) in pigs muscles or other tissues. Infection with cysts called *cysticercosis*. Humans who eat undercooked or raw infected pork swallow the cysts in the meat. the larvae come out of their cysts in the human gut and develop into adult tapeworm, completing life cycle. People get cysticercosis when they swallow eggs that are excreted in the stool of people with the adult tapeworm. This may happen when people drink water or eat food contaminated with tapeworm eggs. People who have tapeworm can infect themselves with the eggs and develop cysticercosis (*autoinfection*). can also infect others if they have poor hygiene, contaminate food or water that other people swallow. People living with others who have tapeworm infection in intestines at higher risk of getting it. Human cysticercosis is found worldwide, especially where it is common in pigs. Both taeniasis and cysticercosis are found in rural areas of developing countries with poor sanitation where pigs roam freely and eat human feces.

Taenia solium

tapeworm

Chagas Disease: T. cruzi: Diagnosis

the diagnosis of chagas disease can be made by observation of the parasite in a blood smear by microscopic examination. a thick and thin blood smear are made and stained for visualization of parasites. However, a blood smear works well only in the acute phase of infection when parasites are seen circulating in blood. Diagnosis of chronic chagas disease is made after consideration of patients clinical findings, as well as by the likelihood of being infected, such as having lived in an endemic country. Diagnosis is generally made by testing with at least two different serologic tests.