Shistosomiasis and Tapeworms Flashcards
What are flukes?
Schistosomiasis Biharzia
What phylum are flukes classified as?
Platyhelminthes
What class are flukes?
Trematoda
What phylum are tapeworms?
Platyhelminthes
What class are tapeworms?
Cestoda
What is the human portion of schistosomiasis?
Cercaria (free-swimming infective stage)
Cercariae penetrate skin
Tail is lost during penetration
Cercariae migrate via blood circulation to the liver of the host and mature
Adult male + Adult female (Gynecophoral canal)
Adults migrate to blood vessels of intestine or bladder; eggs are laid and appear in faeces or urine
S. haematobium
Eggs
What is the snail portion of schistosomiasis?
Eggs S.mansoni Eggs enter fresh water Miracidium hatches from egg Penetrates into snail tissue Developing cercariae Sporocyst in snail (2 generations) Cercariae penetrate human skin
What happens when a schistosoma mansoni egg is in the liver?
Eggs and granuloma → portal vein hypertension→rupture→death
What is the histopathology of the baldder in histopathology?
Bladder can’t stretch
Causes tumours
Chronic inflammation→ tumour
Where are schistosoma haemotobium also found in females?
Veins of vagina
How many women are affected with urogenital schistosomiasis?
9-13 million women, primary in 53 countries in sub-Saharan Africa and eastern Mediterranean
What do dams and irrigation canals provide for schistosoma haemotobium?
Snail breeding sites
What is the natural resistance to schistosoma haemotobium?
IgE antibody- Th2
What drugs are used to treat schistosoma haemotobium?
Praziquantel
In what form is schistosoma haemotobium?
Highly polymorphic