Download Chain of Infectious Diseases

Communicable Diseases
Chapter 24
Lesson: 1
Vocabulary Terms
Communicable disease, pathogen, infection, viruses, bacteria,
toxin, vector
Communicable Disease are…
Communicable Disease is
a disease that is spread
from one living thing to
another or through the
environment.
Pathogens
An organism that
causes diseases is
known as a …
Common pathogens:
-Viruses – bacteria –
fungi, etc
Diseases by Pathogen Type
Viruses
Bacteria
•
Common cold
• Bacterial food borne illness
•
Influenza
•
Viral pneumonia
•
Viral hepititus
•
• Strep throat
Fungi
•
Athlete’s foot
• Tuberculosis
•
Ringworm
Polio
• Gonorrhea
•
Vaginal yeast infecion
•
Mononucleosis
• Lyme disease
•
Chicken pox
•
Herpes
•
Rabies (batman?)
• Pink eye
• Bacterial pneumonia
Infections
• Infections are conditions
that occur when pathogens
enter the body, multiply, and
damage the body cells.
• If the body is unable to fight
off the infection, a disease
develops.
Two familiar diseases
caused by VIRUSES?
Common cold & Flu
Viruses
• Viruses are pieces of genetic material surrounded
by a protein coat.
• Alone they are INACTIVE.
• They need living cells to reproduce.
• After a virus penetrates a cell, called the host cell,
the virus takes control of the cell to manufacture
more viruses.
Bacteria
are single-celled microorganisms that
live almost everywhere on earth.
Some bacteria produce toxins,
a substance that kills cells or
interferes with their
functions.
Like most other organisms that
enter the body of a healthy
individual, bacteria are
usually destroyed by the
immune system.
Most bacterial diseases can be
treated with antibiotics.
Other types of pathogens:
• Fungi are plantlike organisms, such as molds or
yeasts.
• Protozoans are single-celled organisms that are
larger and more complex than bacteria.
• Rickettsias are pathogens that resemble bacteria.
How are diseases transmitted?
• Direct contact
• Indirect contact
• Airborne transmission
Direct Contact
•
•
Pathogens are transmitted by
direct contact with an
infected person or animal or
with something in the
environment.
•
TOUCHING
•
BITING
•
KISSING
Direct contact includes:
•
SEXUAL CONTACT
•
SNEEZING
•
COUGHING
*A pregnant mom can spread
infection to her unborn child
through the placenta.
Indirect Contact
• CONTAMINATED
OBJECTS
• Sneezing on the table
• VECTORS
• An organism that carries and
transmits pathogens to humans
or animals.
• Mosquito, tick, bird
• WATER AND FOOD
• Careless handling & storage
• Salmonella
Some diseases can be
transmitted indirectly,
without being close to the
affected person.
Indirect contact includes:
Airborne Transmission
What are some
strategies to prevent the
spread of communicable
diseases?
Strategies:
• Wash your hands with SOAP.
• Handle food properly.
• Eat a balanced diet (good immune system)
• Avoid unnecessary contact with people who are ill.
• Abstinence? Protection? Sex? What???
• Manage stress, too much make you vulnerable to
diseases.
Bell Ringer 2.8.11
How does the body protect itself against invading pathogens?
Preventing Communicable
Diseases
Lesson: 2
Vocabulary Terms
Immune system, inflammatory response, phagocyte, antigen,
immunity, lymphocyte antibody, vaccine.
Immune System
24/7 your body is exposed to
over a million pathogens. Most
of the time, you body manages
to stay free of infection because
of your immune system.
Your immune system is a
network of cells, tissues, organs,
and chemicals that fights off
pathogens.
Inflammatory Response
• Inflammatory response is a reaction to tissue
damaged caused by injury or infection.
• Purpose: to prevent further tissue damage & HALT
further pathogens from entering.
• Ex: Splinter in finger
• Symptoms: hot, swollen, red, painful = I.R.
Phagocyte
• First guy to respond to the
injured site is the
phagocyte.
• White blood cell that attacks
invading pathogens.
• Engulf pathogens & destroy
them with chemicals.
• Once under control, tissue
repair begins again.
Immune Response
Fig. 24.3
1.
Pathogens invade the body.
2.
Macrophages engulf the pathogen.
3.
Macrophages digest the pathogen and T cells recognize antigens of the
pathogens as invaders.
4.
T cells bind to the antigens.
5.
B cells bind to antigens & helper T cells.
6.
B cells divide to produce plasma cells.
7.
Plasma cells release antibodies into the bloodstream.
8.
Antibodies bind to antigens to help other cells identify & destroy
pathogens.
Vocabulary
• Antigen: substance that is capable of triggering an
immune response.
• Lymphocyte: specialized WBC’s that coordinate
and perform many functions specific to immunity.
• Antibody: proteins that act against specific antigens.
• Vaccine: a preparation of dead or weakened
pathogens that are introduced to the body to
stimulate an immune response.
Passive vs. Active
Immunity
Read page 631
st
1
Body’s
Line of
Defense
-Skin (1st line)
- Tears & saliva (contains enzymes that destroy)
-Mucous membranes (mouth, nose, bronchial tubes)
-Cilia (hairlike projections that line respiratory system)
-Gastric juice (stomach destroys in nose & mouth)
nd
2
Line of D
• Bleeding
• Ex. “wash” the wound & clot
• White Blood Cells aka Leukocytes
• Several kinds
rd
3
Line of D
• Swelling/Inflammation
• Fever
Show Symptoms
Go to Doctor!
Is there a vaccine to
prevent the common
cold?
Developing a vaccine to prevent colds is difficult. More than 200
different viruses can cause the common cold. This means that
more than 200 different vaccines would have to be developed to
prevent this illness.
Care of the Immune System
•
•
Health behaviors greatly reduce
your chance of contracting a
disease or getting an infection.
When you keep your body
strong and healthy, your immune
system is better able to fight off
pathogens!
•
Follow a sensible eating plan to
maintain health and strength.
•
Drink up to 8 glasses of water
EVERY day.
•
Get plenty of GOOD rest.
•
Get an hour of physical activity
each day.
•
Avoid sharing personal items:
toothbrushes, towels, makeup.
•
Avoid ATOD
•
Avoid sexual contact, some STI’s
(HIV) destroys the immune
system.
Chain of Infectious
Diseases
CHAIN
• Pathogen – Virus, bacteria, fungi, etc.
• Host – What’s causing the infection?
• Reservoir - The natural habitat of an infectious agent; Place where an
infectious agent normally lives and multiplies.
• Place of Exit - Way to leave the reservoir.
• Methods of Transmission – How the agent is transmitted to the host direct or indirect or airborne transmission.
• Place of Entry - Way to leave the reservoir.
How do we break the
chain of infection?
•
Mononucleosis
•
Strep Throat
•
Measles
•
Tuberculosis
•
AIDS
•
Diphtheria
•
Meningitis
•
Gonorrhea
•
Chicken Pox
•
Lyme Disease
•
Herpes
•
Pink Eye
•
Rabies
•
Athlete’s Foot
•
Smallpox
•
Ringworm
•
Bacterial Foodborne Illness – Salmonella
•
Malaria
•
Rocky Mountain Spotted Fever
•
Common Cold
•
Thypus (Tyhoid Fever)
•
Hepatitis B
•
Influenza
•
Polio
•
Pnuemonia
Assignment Due:
Name – 1pt
Description – 1pt
Symptoms – 3 pts
Complications – 2 pts
Chain Parts – 2 pts each
Suspected & Prevention – 6 pts
= 25 POINTS TOTAL