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'''Epidemiology'''
 
'''Epidemiology'''
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*Vector distribution
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**[[Biting Flies#Glossinidae|Tsetse flies]] found in riverine, savannah and forest habitats
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**Up to 20% [[Biting Flies|flies]] infected
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**[[Biting Flies|Flies]] infected for life
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*Parasite virulence
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**Some parasitaemic animals survive for long periods of time
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***E.g. ''T. brucei'' and ''T. congolense''
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***Increases the opportunity for infection of [[Biting Flies|flies]]
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**Some trypanosomes kill their host in 1-2 weeks
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***E.g. ''T. vivax''
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***Decreases the chances of [[Biting Flies|fly]] infection
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**Trypanosomes avoid host immune defences by altering glycoprotein coat (surface antigen) before host [[Immunoglobulin - WikiBlood|antibodt]] response
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***'''Antigenic variation''' can occur many times over several months causes relapsing parasitaemia
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*Host response
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**Trypanotolerant wild animals remain parasitaemic for prolpnged periods without showing clincial signs of disease
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***Cause lasting reservoirs of infection
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**Most domestic livestock are susceptible to trypanosomosis
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**Some local breeds of sheep, goats and cattle are trypanotolerant
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***E.g. ''Bos indicus''
    
'''Diagnosis'''
 
'''Diagnosis'''
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