Africa, SE Asia, S & Central America, Caribbean

1. Africa, SE Asia, S & Central America, Caribbean Flu-like cycles; splenomegaly, anemia, thrombocytopenia, CNS damage Infected mosquito bites human –replicate in liver Blood smears: Vivax – Shuffner dots; Faciparum – multiple rings/RBC Chloroquine → primaquine Falciparum: quinine SO4 + doxy,clindamycin, Malarone Africa, Asia, Europe, N &S America Sodium stibogluconate, Paramomycin; follow-up with smears, cultures, or PCR Multi-organ, opp in AIDS; anemia (fatigue), fever Wild animal reservoir: small rodents, dogs, cats; Pro→amastigote in macro, then spread into other tissues Detect amastigotes in macros (visceral use biopsy sample) In macros, then other tissues Afghanistan, Brazil, Iran, Peru, Saudi Arabia, Syria Ulcerative, skin disfiguring Destroy mucous membranes & related structures Bolivia, Brazil, Peru Winterbottom sign in neck, fever, rash, edema, then to CNS; Days-wks inc; Chancre → hemolymphatic → meningoencephalitic Wild animals reservoir: bin fission in blood & other fluids Gambian: Eflornithine Rhodesiense: Melarsoprol Suramin & pentamidine don’t cross CNS Tropical W & Central Africa Thick/thin blood smears, LN aspirates, spinal fluid, serologic, PCR African sleeping sickness E Africa (cattle-raising countries) More virulent & shorter inc than gambiense; acute disease faster & progresses to fatal within 12mo if untreated. Lymphadenopathy uncommon – CNS invasion early Romanas sign: rash & edema around face/eyes; flu, CNS involv. Same, blood transfusion, pregnancy, milk, eat bug feces Chronic hard to find – leaves bloodstream: biopsy Americas Most common <5yo; 30% chronic Nifurtimox, Benznidazol Screwed if chronic Only bad if congenital or ICH: encephalitis, necrotic brain lesions Mature oocytes from cat feces, raw undercooked meat Serology Worldwide Worldwide, mostly tropical & developing Foul-smelling, fatty diarrhea; never fatal Parasite in feces Fecal-oral Sm. intestine Self-limiting diarrhea; can be fatal in AIDS Fecal-oral, waterborne, contact with cattle Oocysts in feces (acid-fast or fluor. stain) Worldwide Sm. intestine Worldwide, mostly tropical & developing If severe: dysentery, spread to organs can be fatal (liver) – adhere, toxins Fecal-oral; NOT a zoonosis Parasite in feces, CT, serology Only flagellated in vaginal or urethral discharge Worldwide Mild vaginitis or urethritis Sex

2. (tapeworms) Pig tapeworm Pig tapeworm Beef tapeworm Hyatid worm Cattle ingest grass contaminated with human feces, humans eat larval form in meat Ingesting fleas infected with cysticercoid Eating pork containing cysticerci Eating eggs from human feces Eating dog feces Scolex attaches to SI, becomes adult with eggs or gravid proglottids Eggs hatch, penetrate intestinal wall, circulate to musculature & develop cysticerci Silent years – hepatic, pulmonary, other organs (brain, bone, heart); cyst rupture: fever, urticaria, anaphylactic shock Scolex attaches to SI, becomes adult with eggs or gravid proglottids Scolex attaches to SI, becomes adult with gravid proglottids None – ab discomfort. Risk of cysticercosis. Rare appendicitis or cholangitis Cysticercosis: most common subQ tissues, brain, eyes Often asymptomatic Same as solium, but more frequently symptomatic Biliary duct obstruction, mass, chest pain, cough, hemoptysis, ab pain Ab discomfort, pruritus, diarrhea IHA, IFA, EIA, ultrasonography & other imaging, fine needle biopsy Eggs/proglottids (corona radiata) Eggs/proglottids Eggs/proglottids (defined circles) Ab detection, biopsy if not brain, high IgE, CT, MRI Pet owners & children Humans Humans Humans SI of canids Pig or human Ox, cattle larval form (cysticercus) in muscle Pig or human Fleas Livestock & humans (where it causes disease) Fecal eggs or proglottids, pig/cow ingests contaminated vegetation Fecal eggs or proglottids, pig/cow ingests contaminated vegetation Gravid proglottids, ingested by larval flea Cyst in muscle – not transmitted unless muscle is eated (livestock) Worldwide Worldwide Worldwide Worldwide Worldwide (sheep-raising countries mostly) Sx to remove cysticerci; symptomatic for neurocysticercosis – albendazole, corticoids Sx (not always effective – can rupture cyst), Albendazole, Mebendazole Prazyquantel Prazyquantel Prazyquantel

3. (Flukes) Lung fluke Liver fluke Crcariae released by snail are free-swimming in water and penetrate skin Ingest inadequately cooked or pickled lobsters, crabs, or shrimp (metacercariae) Cercariea penetrate skin, fail to form schistocomulum and die Eat raw or undercooked vegetables Same Same Migrate to portal blood in liver, become adults; paired adults migrate to mesenteric v.s & lay eggs Migrate to portal blood in liver, become adults; paired adults migrate to mesenteric v.s & lay eggs Excyst in duodenum, invades tissue to hepatic biliary ducts; unembryonated eggs passed in feces Migrate to portal blood in liver, become adults; paired adults migrate to v.s of bladder & lay eggs Excyst in duodenum, invades tissue to lung and matures to adult in cyst (65-90d); cough up then swallow eggs, pass in feces No migration – wander wom doesn’t know where to go Acute: diarrhea, vomiting, enlarged liver, fever Chronic: intermittent blockage of bile duct, inflammation Eggs (proteases) migrate to intestinal lumen or bladder; 50% die in tissue = pathology Same – portal hypertension, ascites, esophageal varices, liver fibrosis (pipestem). Same patho – hematura early, fibrosis of bladder and obstructive uropathy, rare renal failure & hydronephrosis, carcinoma Inflammatory reaction in skin ~30min, resolves 4-7d Acute: diarrhea, ab pain, fever, eosinophilia Chronic: pulmonary manifestations (eggs in sputum) (may persist 20yr) Eggs in feces/urine, ELISA, IFAT, RIA, IHA Lateral spine Eggs in feces/urine, ELISA, IFAT, RIA, IHA Lateral SMALL spine Eggs in feces/urine, ELISA, IFAT, RIA, IHA Terminal spine Eggs in stool (cap on end) Eggs in stool/sputum (takes 2-3mo – pear shape), immunodiagnosis) Humans Humans Humans Humans Humans/livestock Bird Shellfish: lobsters, crabs, shrimp Snails Snails Snails Snails Snail/mollusc Egg from feces/urine, hatches to release miracidia Egg from feces/urine, hatches to release miracidia Egg from feces/urine, hatches to release miracidia Unembryonated eggs passed in feces Unembryonated eggs from feces or sputum, become embryonated in water None – scistosome dies in human Worldwide (sheep and cattle, raw watercress) Africa Africa & E Brazil Indonesia, China, Japan Americas, Afria, SE Asia Praziquantel and Oxamniquine Praziquantel and Oxamniquine Anti-inflammatory drugs Praziquantel and Oxamniquine Triclabendandazole Praziquantel

4. Pinworm Whipworm Pinworm Hookworm Threadworm Filariform larvae on vegetation penetrate skin (usually via hair follicle) and enter capillaries Filariform larvae penetrate skin Ingestion of eggs; Eggs become infective (embryonate) after 6hr Ingesting embryonated eggs (take 2-4wk in soil) Ingestion of larvae in meat Ingesting embryonated eggs (take 3-4wk, best in warm sandy soil) Kept in circulation by rodents being eaten by carnivores Hatch in SI and larvae migrate to colon; gravid migrates to perianal region at night to lay eggs Hatch in SI and larvae migrate to cecum & asc. colon (fixed there); females live 1-2yr Hatch SI, enter lamina propria and mesenteric capillaries and travel to lung via liver, heart; molt in alveoli and migrate up, swallowed, mature in SI; mate in 6wk, eat food in SI Once in capillary, migrate to lung, up to epiglottis, swallowed; adults in SI live 4-5yr and eat blood (can be >1000worms) Same cycle as Necator, but eggs in intestine hatch to form rhabditiform larvae, molt in GI(which can autoinfect – penetrate tissue to lungs, repeat) Larvae hatch in SI & mature; adults mate, larvae deposited in mucosa and enter circulation, become encysted in striated muscle Iron deficiency anemia Often asymptomatic; perianal pruritis at night, can lead to bacterial superinfection, ab pain, anorexia, can infade female GU Often asymptomatic; severe: GI problems, rectal prolapse, growth retardation, bloody diarrhea, anemia Migration & molt induces IgG & IgE; pneumonitis, liver enlargement, aberrant migration (bile duct) Invasive: ground itch Pulmonary: heavy infection pneumonitis, eosinophilia, cardiac probs, GI or nutritional symptomsIntestinal: ant 1/3 SI Wk1: GI, asymptomatic Wk2: muscle invasion, weakness, uncommon myocarditis (fatal), CNS invasion (paralysis, coma) Eggs (dark center with thick white shell), sometimes whole worms expelled Rhabditiform larvae in feces, sputum smears if disseminated, ELISA Myositis & eosinophilia, Hx of diet, EIA, muscle biopsy, microscopy Eggs on anal skin (Scotch tape test) (mottled inside with clear ring outside) Eggs in feces (football, “plugs” at each end) Eggs in stool (blunty ovoid egg with transparent shell) Humans – direct life cycle (monkey & dog reservoir) Humans – direct life cycle Humans – direct life cycle Humans – direct life cycle Humans – direct life cycle Humans Eggs Eggs Eggs Eggs Rhabditiform larvae Not – encysted n muscle Tropical/subtropical, but also temperate. Mainly rural, institutional, & lower socioeconomic groups Worldwide – more schoolkids, crowded living, temperate regions Most common helminth in US Worldwide – tropcial, subtropical Most common helminth Worldwide – mostly warm, moist climates Necator: Americas & AustraliaAncylostoma: Middle East, Africa Worldwide – kids, tropical areas Worldwide – mainly Europe & US (rare) Light infection/endemic area: not treated US: albendazole Steroids, mebendazole, albendazole Migration: none Mebendazole, albendazole Ivermectin Pyrantel pamoate Mebendazole

5. Lymphatic filariasis/ elephatiasis River blindness Cutaneous larva migrans Guinea worm Drinking contaminated standing pond water Mosquito bite Black fly bite Ingestion of eggs with larvae Filariform larvae penetrates skin Eat infected fish with larvae Larvae released when copepods die, penetrate stomach & intestine, mature & multiply; fertilized female migrates to surface of skin & causes blister to discharge larvae (1yr) Fly bites, goes into subcutaneous tissues, adults mature in nodule and produce unsheathed microfilariae (found in skin & lymphatics of CT) Adult in lymphatics produce sheathed microfilariae that migrate into blood and lymph channels Larvae penetrate gastric mucosa Intensely pruritic serpiginous track in upper dermis Larvae invade tissue Prolonged asymptomatic, lymphangitis and “filarial fever” for years, lymphatic blockage and lymphadema, chyluria Microfilariea live 1-2yr and die in skin or eyes – inflammation - scarring Adults live 10-15yr Symptoms 9mo-2yr Painful blister, then worm emerges (1-3wk) violent ab pain, N/V in hours; can mimic Crohn’s if in bowel (severe eosinophilic granulomatous response) Asymptomatic or visceral larva migrans (VML): fever, coughing, anemia, eosinophelia, positive titers Microfilariae in peripheral blood, filarial Ag, urine examination, CBC, elevated IgE Microfilariae in a snip-snip biopsy sample, Ab/Ag detection, DEC patch test Eosinophelia, positive titers Worm emerging from blister Gastroscopic exam & biopsy Fish/squid – wander worm in humans Dogs/rabbits – wander worm in humans Dogs/cats – wander worm in humans Humans Humans Humans Copepods Mosquito Black fly (Simulium) Larvae from emerging female Sheathed microfilariae from blood Unsheathed microfilariae from blood Rural, isolated areas in Africa Tropical areas worldwide Africa, Central & S America, Middle East Worldwide Clean lesion & local antibiotics; mechanical extraction of worm Oral Ivermectin and Diethylcarbamazine, Sx Surgical or endoscopic removal Albendazole + antiinflammatory med Self limiting; if severe: albendazole, ivermectin, Sx removal Ivermectin, corticoids Doxy for adults