Sources and reservoirs
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Sources (infected animals or contaminated materials) from which the zoonotic diseases are transmitted to the susceptible hosts (human beings).
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The term ‘source’ refers to the immediate source of infection and may or may not be a part of reservoir.
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In case of reservoirs, the niche (infected persons or animals, arthropods, contaminated soil or substances) that zoonotic pathogens usually inhabit in such a manner that can be transmitted to a susceptible hosts (human beings).
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The reservoir may be a primary or secondary host. It may be clinical or subclinical or carrier or latent infection.
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Carrier means an infected host that harbors a pathogen without showing clinical signs, but releasing the infectious pathogen in the secretions and excretions either for short period of time (temporary carriers) or for long period of time (chronic carriers).
- Example:
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In case of tetanus, the source and the reservoir are the same that is soil.
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But, in the case of typhoid, the source of the infection may be faeces or urine of the infected patients or contaminated food, milk or water and reservoir may be a case or carrier.
Transmission link between infected and susceptible hosts
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Last modified: Wednesday, 16 May 2012, 6:31 AM