This Week in Parasitism

Vincent and Dickson converse with Peter Hotez about global health, vaccinology, and neglected tropical diseases.

Vincent and Dickson discuss medical entomology with Robert W. Gwadz, Assistant Chief of the Laboratory of Malaria and Vector Research at NIAID.

Vincent and Dickson continue their discussion of trematodes, or flukes, which have a snail as a reservoir host.

Vincent and Dickson take on the schistosomes, agents of a series of related diseases in humans referred to as schistosomiasis.

Vincent and Dickson review Wuchereria bancrofti, the nematode that causes lymphatic filariasis, also known as elephantiasis.

Vincent and Dickson discuss the life cycle and pathogenesis of Onchocerca volvulus, the vector-borne filarial nematode parasite that causes onchocerciasis, or river blindness.

Vincent and Dickson review the life cycle and pathogenesis of the world's most unusual parasite, Strongyloides stercoralis.

Vincent and Dickson discuss possibly the most socially and politically important nematode of humans, the hookworm Ancylostoma duodenale and Necator americanus.

Vincent and Dickson review the biology and pathogenesis of Ascaris lumbricoides, one of the largest nematodes to infect humans.

Vincent and Dickson continue their discussion of nematodes with the whipworm Trichuris trichiura. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Trichuris trichiura adult female (jpg) Trichuris trichiura adult male (jpg) Trichuris trichiura in situ (jpg) Trichuris trichiura life cycle (jpg) Exploitation of the intestinal microflora by T. muris Letters read on TWiP 20 Contact Send your questions and comments (email or mp3 file) to [email protected]. Subscribe (free) Click here to receive an email notification when a new episode of TWiP is published

Vincent and Dickson move on to nematodes with a discussion of the pinworm Enterobius vermicularis. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Enterobius vermicularis adult female (jpg) Enterobius vermicularis in appendix (jpg) Enterobius vermicularis embryonated eggs (jpg) Enterobius vermicularis life cycle (jpg) Letters read on TWiP 19 Contact Send your questions and comments (email or mp3 file) to [email protected]. Subscribe (free) Click here to receive an email notification when a new episode of TWiP is published.

Vincent and Dickson discuss the intracellular parasite Cryptosporidium, which causes diarrheal disease in most mammalian species. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Cryptosporidium parvum electron micrograph (jpg) Cryptosporidium parvum meronts (jpg) Cryptosporidium parvum life cycle (jpg) Cryptosporidium page at CDC Letters read on TWiP 18 Contact Send your questions and comments (email or mp3 file) to [email protected]. Subscribe (free) Click here to receive an email notification when a new episode of TWiP is published.

Vincent and Dickson continue their discussion of protozoan parasites that cause diarrhea with a review of amebic dysentery caused by Entamoeba histolytica. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Entamoeba histolytica cyst (jpg) Entamoeba histolytica trophozoite (jpg) Entamoeba histolytica life cycle (jpg) Galactose prevents attachment of amoebae to cells (jpg) Entamoeba histolytica life cycle (jpg) Charcot-Leyden crystal (jpg) Letters read on TWiP 17 Contact Send your questions and comments (email or mp3 file) to [email protected]. Subscribe (free) Click here to receive an email notification when a new episode of TWiP is published.

Vincent and Dickson review the life cycle and pathogenesis of the flagellated protozoan parasite Giardia lamblia. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Giardia lamblia trophozoite (jpg) Giardia lamblia cyst (jpg) Giardia lamblia life cycle (jpg) Heather's view of T. canis life cycle (pdf) Letters read on TWiP 16

Vincent and Dickson discuss the life cycle and pathogenesis of the protozoan parasite Trypanosoma. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Metacyclic trypanomastigote (jpg) Tsetse fly (jpg) T. brucei life cycle (jpg) T. brucei parasitemia (jpg) Kissing bug nymph (jpg) T. cruzi life cycle (jpg) Letters read on TWiP 15

Vincent and Dickson consider the life cycle and pathogenesis of the protozoan parasite Leishmania. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: L. braziliensis life cycle (jpg) L. donovani life cycle (jpg) L. tropica life cycle (jpg) L. major lesion (jpg) Transgenic mosquito delivers Leishmania vaccine (thanks, Geoffrey) Plasmodium falciparum accompanied human expansion out of Africa (thanks, Prasad) Who speaks for the guinea worm? (thanks, Michael) Letters read on TWiP 14

Vincent and Dickson continue their discussion of the obligate intracellular protozoan Toxoplasma gondii with a consideration of the clinical consequences of infection and pathogenesis. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Isopod fish parasites (thanks, Kevin!) Farmscraper on Word Spy (thanks, Mitchell!) Toxoplasma and personalities (thanks, Greg!) Science podcast (July 2) on parasites and intelligence (transcript - thanks, Jim!) Letters read on TWiP 13

Vincent and Dickson introduce the obligate intracellular protozoan Toxoplasma gondii, one of the most successful parasites on earth. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Global clinical burden of malaria (PLoS Medicine) T. gondii sporulated oocysts (jpg) T. gondii tachyzoites in parasitophorous vacuole (jpg) T. gondii life cycle (jpg) Insect bioterrorism conference (thanks, Don!) Parasite of the Day (thanks, Douglas!) World Science Festival Letters read on TWiP 12

Vincent and Dickson continue their discussion of malaria, with emphasis on clinical aspects of the disease. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: The quest for a malaria vaccine (Meet the Scientist 49) Science issue on malaria and tuberculosis Malaria pathogenesis (pdf) Malaria pathogenesis (jpg) Letters read on TWiP 11

Vincent and Dickson trace the life cycle of Plasmodium in a mosquito and in a human host. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Mosquito cycle - sporogany (jpg) Plasmodium falciparum cycle (jpg) Plasmodium vivax cycle (jpg) Plasmodium falciparum ring forms and gametocytes in blood (jpg) Plasmodium stages (jpg) Letters read on TWiP 10

Vincent and Dickson move on to protozoan parasites with a discussion of the early history of malaria. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Malaria history at CDC Radio New Zealand show on hookworms (thanks James!) Tapeworm brain infection serious health concern (thanks Jim!) Pig farmers try to limit pork tapeworm spread (thanks Gopal!) Bizarre tongue-eating fish parasite (thanks Arsen!) Letters read on TWiP 9

Dickson reads his story about sparganosis caused by the diphyllobothroid tapeworm Spirometra mansonoides. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Spirometra life cycle (jpg) Dickson on vertical farming (CNN episode on YouTube, thanks Jesse!) Laboratory identification of parasites (CDC, thanks Michael!) Gold nanoparticles take out brain parasite (Cosmos Magazine, thanks Gary!) Letters read on TWiP 8

Vincent and Dickson continue their discourse on tapeworms, covering the fish and dog varieties. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: FAT the enemy that is shortening your life is BANISHED. How? With sanitized tapeworms. Easy to swallow! (jpg). D. latum life cycle (jpg) D. latum adult (jpg) Diphyllobothrim proglottid (jpg) Diphyllobothrim bothria (jpg) Coracidium hatching from egg (jpg) Dog tapeworm life cycle (jpg) The Alien lifecycle (jpg)

Vincent and Dick talk about the anatomy and life cycle of beef and pork tapeworms, and why House was wrong about neurocysticercosis. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Taenia saginata life cycle (jpg) Taenia saginata adult (jpg) Taenia saginata scolex (jpg) Taenia saginata gravid proglottid (jpg) Taenia solium life cycle (jpg) Taenia solium adult (jpg) Taenia solium scolex (jpg) Facial cancer in Tasmanian devils (thanks PhogDog!) Science Picks Dickson Peace through vaccine diplomacy by Peter HotezVincent Parasite Rex by Carl Zimmer

Vincent and Dick discuss the nurse cell, a unique structure formed in the host muscle by Trichinella species. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Infective muscle larva (jpg) Schematic of a larva invading a muscle cell Nurse cell formation (scroll down the page) Dickson's gallery of Trichinella images Electron micrographs of stichocytes Weekly Science Picks Dickson Every Living Thing by Rob Dunn

Vincent and Dick trace the life cycle of Trichinella spiralis in an infected host. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: Trichinella life cycle (jpg) Newborn larva entering muscle cell (jpg) Adult T. spiralis in columnar epithelial cell (jpg) Adult female T. spiralis (jpg) Infective first stage T. spiralis larva in Nurse cell in muscle tissue (jpg) Adult female T. spiralis with fully formed larvae in uterus (jpg) Adult male T. spiralis with claspers on tail (jpg) Clinical correlations in trichinosis (jpg) Letters read on TWiP #4 Weekly Science Picks Dickson David Scharf's pictures of microbial lifeVincent The Nobel Laureate Meetings at Lindau

Vincent and Dick distinguish among intracellular and extracellular parasites, then discuss the history and general characteristics of Trichinella spiralis. Host links: Vincent Racaniello and Dickson Despommier Links for this episode: The History of Trichinella at Trichinella.org Parasite genome databases at the European Bioinformatics Institute List of parasite genome projects Weekly Science Picks Dickson The Doctor and the Devils

Vincent and Dick classify parasites according to whether or not they are transmitted by a vector, then consider the implications of long-lived parasites. Host links: Vincent Racaniello and Dickson Despommier

Vincent and Dick provide an overview of parasites and parasitism. Host links: Vincent Racaniello and Dickson Despommier Weekly Science Picks Dick The Black Cloud by Fred HoyleVincent Parasitic Diseases by Despommier et al.