Download Communicable Disease - Parma Middle School

Communicable Disease
Preventing the Spread of Disease
 Disease is an illness that affects the proper
functioning of the mind or body.
 A communicable disease is one that can be passed
from one person to another.
 A non communicable disease is one that can’t be
passed.
Causes of Communicable Diseases
 Pathogens are tiny organisms that cause disease.
 An infection is a condition that occurs when
pathogens enter the body, multiply, and damage
cells.
 Bacteria are tiny one celled organisms that live
nearly everywhere.
Bacterial Diseases
 Strep
 Tooth decay
 Boils
 Pneumonia
 Impetigo
 Many bacterial diseases can be treated with
antibiotics. Viral infections can’t. They are now
treated with prescribed medication.
Viral Disease
 A virus is the smallest disease-causing organism.
 Examples:
 Cold
 Flu
 Hepatitis
 Measles
 Mumps
 Chicken pox
Other types of Pathogens
 Fungi are primitive life-forms that feed of organic
materials. Example- Ringworm
 Protozoa are single-celled organisms that are usually
harmless but that can cause certain diseases.
Example-Malaria
 Rickettsias- disease causing organisms that resemble
bacteria but multiply like viruses. Example- Rocky
Mountain Spotted Fever
How are Pathogens Spread?
 Direct contact-body fluids, kissing
 Indirect contact-sharing drinking glasses
 Contact with a Vector (an insect)
 Other contacts- food, water, undercooked meat.
Preventing the spread of disease
 Good personal hygiene
 If sick determine the contagious period.
The Body’s Defenses Against Infection
 First line of Defense-stop the entry.
 Eyes, skin, stomach, mucous membranes and saliva.
 The immune system is a combination of body
defenses made up of cells, tissues, and organs that
fight off pathogens and disease.
 Immunity is your bodies ability to fight off disease.
The Lymphatic System
 A secondary circulatory system that helps the body
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fight pathogens and maintains a fluid balance.
White blood cells are called lymphocytes.
B cells produced in the bone marrow, they help
develop immunity to pathogens.
T cells are produced in the thymus gland, they attack
invading pathogens.
Immunity is present at birth.
Vaccinations-figure 17.3, pg. 453
The Lymphatic System
Review
1.
What are 4 risk factors associated with
communicable disease?
2. How can you protect yourself from disease?
3. How does the immune system fight disease?
4. Read pages 454-457.