Transcript Communicable Disease

Communicable Disease
Disease passed from one person
to another
Infectious Disease
5 main kinds of Germs
1. Virus
» Most common, invade healthy cells and
reproduce
» Can not survive outside host cell
» Resistant to antibiotics
» We can treat symptoms, but the body must fight
off the disease on its own
» Vaccinations prevent and are the most effective
Examples are colds, flu,
chicken pox, measles, mumps
https://www.youtube.com/watch?v=Rpj0emEGShQ
2. Bacteria
» Self-reproducing germs without host cells.
They get in the body and multiply
» Some are helpful and some cause sickness.
» Most bad ones can be killed with
medicine/ antibiotics by eating away the
cell membrane
Examples are strep throat, pinkeye
3. Fungi
»Protective capsules surround the cell
wall and protect from phagocytes
»Usually easily treated with medicine
Examples are athletes foot, ringworm
4. Protozoa - Mainly transmitted
by bug bites Ex. Malaria, lyme
disease
 5. Rickets- Animal like
organisms in bad water.
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What Diseases Need To
Make Us Sick
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Host susceptibility
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Age- Young and old more suseptible
General health, immune status
Risk behaviors
Prevention behaviors
Route of Transmission
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Portal of entry
– Nose, Mouth, Cut, Skin
» Exposure does not always equal infection
– Direct- Skin to skin contact
– Indirect- Airborne (sneezes/coughs), sharing
drinking glasses
– Vectors/carrier- Animal or bug bites,
– Vehicles- Contaminated food, water
How Sick Will I Get?
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Depends upon:
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How strong the germ is
Dose of infectious agent
Resistance/immunity of host
Mode of entry
All must exist to create risk
Exposure does not mean person will
become infected
4 Disease Stages
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1. Incubation/Infected Period
– Period of infection, illness cannot be
transmitted to another host
– Symptoms start to build
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2. Infectious Period
– Period after an infection when agent can be
transmitted to another host
– Symptoms start to show: Cough, Sneeze,
Fever
Disease Stages
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3. Disease/Sick Period
– When the illness sets in
– Person displays all symptoms
4. Recovery Phase
– Start to feel better
– Body overcomes disease and immunity
develops
Infected Infectious
Sick
Recovery
The body’s defense system against disease
IMMUNE SYSTEM
The body basically has 3 Lines of Defense
1st Line
-Skin- Protective barrier
-Mucous membranes- Nose, throat, eyes trap and eliminate germs by
coughing and sneezing
-Saliva -Tears
-Stomach acid
2nd Line
-Rising body temperature (fever)
-White blood cells- Phagocytes surround and kill germs
-Interferon- A chemical released by WBC’s to stop the spread of
viruses
3rd Line- The Lymphatic System- Carries lymphocytes
which destroy invaders
T-cells- The brains of the system
Memory T-cells- Remember what a disease is so we
can’t get sick with it again.
B-cells- The workers of the system, eat and destroy germs
OtherAntibodies- Stay in your system and fight disease
Immunity- Body’s ability to resist germs
Immunization/Vaccines
and
Antibiotics
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Vaccines- A small or dead dose of a
disease that builds antibodies.
Prevention of any illness is always
better than treatment
Antibiotics- Powerful medicines that
fight bacterial infections.
https://www.youtube.com/watch?v=-iE-JbtxB6w
http://muddlemaster.com/humankneads/id130.html