Download What is an infectious disease?

What is an infectious disease?
An infectious disease is caused by the
presence of a living organism in your
body.
Pathogen: an organism that
causes disease (Germ)
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Host: organism that the pathogen invades.
Contagious: capable of spreading the disease to
another person.
Susceptible: person who can potentially get the
disease.
Immune: resistant to the pathogen.
Carrier: infected by pathogens but show no
symptoms of the disease BUT can pass the
disease to others.
4 Kinds of Pathogens
1.
2.
3.
4.
Bacteria: Strep throat, Tetanus
Viruses: Cold, Flu, HIV
Fungi: Athlete’s Foot, Ringworm
Protist: Malaria, Dysentery
How Pathogens Are Spread
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Infected People:
direct physical
contact
Soil, Food, and
Water: occur naturally
ex)Cholera
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Contaminated Object:
towels, rusty nail
ex)Tetanus
Animals: can be
infected with the
disease (Rabies) or
serve as a vector:
organism that can
transmit the disease
but is not infected
(Malaria)
Conditions Favorable to Disease
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1.
2.
3.
4.
Epidemic: widespread outbreak of an
infectious disease in which many people
are infected at the same time.
Overcrowding
Lack of Sanitation
Climate (Warm, Wet)
Contaminated Water Supply