Intro To Parasitology Flashcards
What is a parasite?
An organism tha lives in another organism and gets its food at the expense of a host.
Which parasitic disease causes most deaths globally?
Malaria
What are the different types of parasites?
Protozoa
Helminths (worms- round, tape, flukes)
Arthropods (hard shell - lice, ticks mites)
Protozoa
(Malaria)
Fecal-oral route
Malaria
Mosquito vector
Stained blood film shows infected cells (Thick and thin blood films)
Complex life cycle
Drugs- bite avoidance and vector control much more important than medication.
Malaria control
Nets (ITN)
Prophylaxis
Amoebic dysentery
Diarrhoea with blood/pus (inflammatory process in colon)
Cysts formed in stool
Intestinal/ liver infections
Amebic liver abscess
Reddish-brown pus
Anchovy pus
Leishmaniasis
Type of Protozoa
Skin /mucosal ulceration
Infection by bite of sandfly
Helminths
Worms:
Nematodes (round worms)
Custody’s (tapeworms)
Trematoda (flatworms)
Most common round worm in UK?
Enterobiasis (pin worm)
Perianal itching
Ova seen (cysts) using sellotape under slide
Ascaris lumbricoides
Nematode
Often asymptomatically infected
Largest nematode
Mass of worms obstruct small intestine.
Cestodes
Tape worms
Exist in meat
Human - definitive host, cyst turns to adult tapeworm
Ova seen in microscopy of stools.
Tania solium - can lead to neural disorders
Echinococcus - carried by dogs, wolves, foxes
Cysts from in liver over a long time - latent period extensive
Surgical resection must involve full cyst.
What Aries echinococcus?
Dogs,
Foxes
Wolves
Schistomiasis
Trematodes High rates near fresh water Ova excretes in urine.faeces Intermediate host = snail Penetrate human skin (feet) ‘swimmers itch’ Mature in liver into worms LAy eggs that cause intestinal inflammation ‘Katayama fever’
What is katayame fever a result of?
Schistosomiasis
What are snails an intermediate host of?
Schistosomiasis
What can schistosomiasis lead to?
Bladder cancer from Haematuria
What is helminths infection often accompanied by?
Elevated IgE
Eosinophilia
What is eonsiphilia?
??
How do you diagnosis parasitic infections?
Microscopy of different stages
Parasites, cysts, ova in species
Culture rarely possible
How do you diagnosis malaria?
Blood films (thick and thin films)
Blood test - easily accessible
Why can serology be useful in detection of parasites?
Detection of antibodies
When parasite is located in deep tissue sites - cannot use other methods
