Toxoplasmosis
Toxoplasma gondiiNeglected in USA CatWarm-blooded animals Fecal-oral, ingest undercooked meat, transplacentalBlood, tissues Asymptomatic, lifelong latent. Severe in utero complications, cognitive and ocular. Encephalitis in AIDS, with multiple ring enhancing lesions (MRI) from cysts. Serology, biopsy (rare) Pyrimethamine (teratogen: use spiramycin in pregnant women) plus sulfonamides or clindamycin or atovaquone (if sulfa allergy). Prophylactic trimethoprim if CD4 48hrs old) or garden, especially if pregnant
Babesiosis
Babesia microtiGlobally CommonDeer tick Small rodents. Human (incidental) By deer tick (also transmits Lyme disease) RBCs only Hemolytic anemia and thrombocytopenia. Rare: hepatosplenomegaly. Blood smear (Maltese cross). Molecular analysis (CDC can do this). Atovaquone and azithromycin. Clindamycin and quinine. Both humoral and cellular factors are involved in immunity to babesiosis.Stay out of the woods, especially in springtime (tick nymphs); wear DEET in woods
Cryptosporidiosis
Cryptosporidium hominis / parvumGlobally commonHuman livestock Fecal-oral. Water supply (resistant to mild chlorination) Intestine Lose 12 L of water per day (20 L in AIDS). Otherwise similar to Giardia. Cysts in stool, IHC. There are no effective drugs against cryptosporidium. Oral rehydration. Possible immunity Boil water
Malaria
Plasmodium falciparum / knowlesi / vivax / ovale / malariaeGlobally commonMosquito Humans, primates (for P. knowlesi) Bite from female Anopheles. Needle sharing RBCs, liver Fevers and chills, synchronous with merozoites (24hrs for P. falciparum and P. knowlesi, 48hrs for P. vivax and P. ovale, 72hrs for P. malariae). Cerebral malaria (not in kids t have immune responses that assist Plasmodium). Anemia, especially in the young. Respiratory distress syndrome. Blood smear. P. falciparum makes multiple rings per RBC. Can be difficult to distinguish different species by blood smear. Chloroquine, mefloquine, quinine, malarone (atovaquone and proguanil) Cannot make an effect immune response due to antigenic variation mechanisms Prophylactic malarone. Repel and net mosquitos. New vaccine has some effectiveness. Reduce mosquito populations. Duffy negative (endemic to Africa) prevents P. vivax infection.
Hydatid disease
Echinococcosis granulosusOther Canine tapewormDogs Ungulates, humans Ingest eggs from dogs that ate livestock meat (fecal-oral transmission) Lungs, liver, spleen, kidney, heart, bones, CNS Hydatid cysts (liver and lung), anaphylaxis upon rupture Imaging, serology Surgical removal, percutaneous drainage, albendazole Antibodies to hydatid cyst De-worm dogs. Don’t feed them livestock
Cysticercosis (Taenia saginata)
Taenia saginataNeglected in USA Beef tapewormHumans Cows Ingest cysticeri from meat (taeniasis), ingest eggs from feces (cysticercosis) Intestine Taeniasis: Nausea, vomiting, diarrhea, weight loss, abdominal discomfort. Cysticercosis: Neurocysticercosis Proglottids in stool, imaging Praziquantel, niclosamide or albendazole, dexamethasone (to reduce inflammation) Reinfection possible Cook your beef
Cysticercosis (Taenia solium)
Taenia soliumNeglected in USA Pork tapewormHumans Pigs Ingest cysticeri from meat (taeniasis), ingest eggs from feces (cysticercosis)Intestine, lung Taeniasis: Nausea, vomiting, diarrhea, weight loss, abdominal discomfort. Cysticercosis: Neurocysticercosis Proglottids in stool, imaging Praziquantel, niclosamide or albendazole, dexamethasone (to reduce inflammation) Reinfection possible Cook your pork
Cysticercosis (Diphylobothrium bothrium)
Diphylobothrium bothriumNeglected in USA fish tapewormHumans Copepods in fish Raw or undercooked fish Intestine B12 deficiency, anemia Proglottids in stool, imaging, pernicious anemia Praziquantel, niclosamide or albendazole, dexamethasone (to reduce inflammation) Reinfection possible Cook or freeze your fish
Trypanosomiasis
Trypanosoma brucei / rhodesiense / gambiensesub-Saharan only Sleeping sicknessHumans Tsetse fly Bite from tsetse fly Blood (never intracellular) Lymphadenopathy, dementia, confusion, motor impairment, sleepiness, death through coma. Blood smear, CSF analysis (T. rhodesiense), card agglutination test (not in USA, inaccurate) Early stage: pentamidine, suramin. Late (post-BBB) stage: malarsopral, eflornithine (+/- nifurtimox) None. Antigenic variation by pathogen Vector control, vector avoidance, aggressive treatment
Chagas Disease
Trypanosoma cruziNeglected in USAReduvid bugs Rats, cats, dogs, oposums, humans (dead end) Bite from reduvid bug (with fecal contact). IV drug use, transplantation, transfusion. Blood, lymph, tissues Acute: 2-4 months after bite, fever, chagoma (Romana’s sign: swollen lateral eye), organ failure especially in children. Chronic: 10-20 years after bite, no circulating trypomastigotes, only persistent amastigotes in tissue, causes chronic inflammation, manifests as a heart attack. Acute: trypomastigotes in blood, antibody test. Chronic: xenodiagnosis Acute: benznidazole, nifurtimox. Chronic: noneAntibodies are detectable Vector control, good housing, screen blood supplies
Leishmaniasis
Leishmania mexicana / braziliensis / chagasi Globally commonSandfly Humans Bite from sandfly Blood and tissues Cutaneous leishmaniasis: ulcerative sore at primary site, with satellite lesions. Spontaneous healing. Mucocutaneous leishmaniasis can spread years later and ulcurate the nasopharynx. Visceral leishmaniasis causes fever, wasting, splenohepatomegaly. Staining for amastigotes Cutaneous: self-resolving. Mucocutaneous: amphotericin B (expensive) or antimonials. Viceral: Amphoteracin B, miltefosine. Strain-specific Vector control, vector avoidance, aggressive treatment
Trichinosis
Trichinela spiralis Other Tissue wormBears and swine Humans (dead end) Ingest undercooked meat from bear or pigMuscle and intestine Nausea, cramps, fever, conjunctivitis, muscle pain, cardiac and neural dysfunction Eosinophilia, periorbital edema, myositis, fever, serology Mebendazole, albendazole, corticosteroids Antibodies are detectable Cook or freeze your pork and bear meat
Toxocariasis
Toxocara canis / cati Neglected in USA Tissue wormDogs / cats Humans (incidental) Ingest eggs from soil Blood Local necrosis, hepatomegaly, pulmonary complications, ocular lesions, neurological symptoms ELISA, history of geophagia Mebendazole, albendazole, corticosteroids Asthmatic and immune hypersensitivity common De-worm dogs. Dispose of dog waste
Pinworm
Enterobius vermicularis Other Lumenal wormHuman none Ingest eggs from another person (fecal-oral transmission) Intestine Perianal pruritus, urogenital invasion, psychological trauma Scotch tape test Pyrantel pamoate, mebendazole, albendazole None Don’t consume human feces
Whipworm
Trichuris trichuria Other Lumenal wormHuman none Ingest eggs from soil (fecal-oral transmission) Intestine Bloody stool, bacteremia, anemia, prolapse, impaired growth Eggs in stool Ivermectin, mebendazole or albendazole Some evidence for acquired immunity Wash and cook your produce
Ascariasis
Ascaris lumbricoides Globally common (NDP) Lumenal wormHumans none Ingest eggs from soil (fecal-oral transmission) IntestineIntestinal obstruction, poor development Eggs in stool Ivermectin, mebendazole or albendazole Allergic inflammation from larval migration through lungs Wash and cook your produce
Necatoriasis (Necator americanus)
Necator americanusOther Hookworm Humans none From soil through skin Intestine Pruritis at penetration site (often between toes), bronchitis, anemia, poor development Eggs in stool, anemia Pyrantel pamoate, albendazole & mebendazole, (NOT corticosteroids!) Asthmatic pathology with repeated infection Wear shoes
Necatoriasis (Ancyclostoma duodenale)
Ancyclostoma duodenaleOther Hookworm Humans none From soil through skin Intestine Pruritis at penetration site (often between toes), bronchitis, anemia, poor development Eggs in stool, anemia Pyrantel pamoate, albendazole & mebendazole, (NOT corticosteroids!) Asthmatic pathology with repeated infection Wear shoes
Strongyloidiasis
Strongyloides stercoralis Other Hookworm Humans none From soil through skin Intestine Dysentery, pulmonary manifestations, rash on lower body Stain stool with iodine, auramine O, Gram stain Ivermectin, thiabenazole Asthmatic pathology with repeated infection Wear shoes
Amebiasis
Entamoeba histolytica / dispar OtherHuman none Fecal-oral or anal sex Intestine (and liver in invasive disease) Asymptomatic (probably E. histolitica only): chronic infection, hepatitis. Symptomatic (E. dispar): diarrhea, dysentery, liver dissemination. Cysts and trophozoites in stool. PCR, serology. Metronidazole, tinidazole, paromycin (lumenal phase) Possible immunity where endemic Don’t consume human feces, use condoms
Giardiasis
Giardia lamblia OtherHuman none Fecal-oral Intestine Onset of 2 weeks, explosive diarrhea (never bloody). Cramping and nausea. Malabsorption syndrome. Cysts in stool, ELISA. Metronidazole, tinidazole, nitazoxanide, paromomycin (pregnant women) Possible immunity where endemic Don’t consume human feces
Trichomoniasis
Trichomonas vaginalis Neglected in USAHumans none Sexually transmitted Lumenal, urogenital 70% of infected are asymptomatic. Female: vaginitis, vaginal discharge with unusual odor. Male: few symptoms, itching inside of penis Microscopic observation, culture Metronidazole No immunity Condom use, screening
Schistosomiasis
Schistosoma mansoni / japonicum / haematobium Globally common FlukeHumans Snails Invasive, aquatic free-living cercaria penetrate skin Veins to gut, or bladder (for haematobium) Rash at site of penetration, fever, headache, nausea, Katayama syndrome, abdominal pain, diarrhea, bloody stool, heamaturia (for haematobium). Chronic: eosinophilia and granulomas, liver fibrosis, hepatomegaly, splenomegaly, bladder ulceration and cancer (for haematobium) Eggs in stool, or urine (for haematobium). Serology Praziquantel Antibodies can target schistosomula, not adults Treat infections, stay out of water, kill those snails
