Preventing Communicable Diseases

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Preventing Communicable Diseases
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Preventing Communicable Disease

1. Wash hands frequently
2. Eat a balanced diet and be physically active
3. Avoid the use of tobacco, and other drugs
4. Avoid sharing utensils, makeup, combs and
   brushes, and other personal objects
5. Prepare and handle food safely.

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Preventing Communicable Disease

• 6. Avoid unnecessary contact with people who are
  ill.
• 7. Cover your mouth when coughing or sneezing.
• 8. Keep immunizations up-to-date
• 9. Practice abstinence from sexual activity.
• Manage stress, which can make you vulnerable to
  illness

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The Immune Response
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The Innate Immune Response

• Inborn, nonspecific (general) defenses against
  infection

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Physical Barriers

• Your bodys first line of defense.
• Unbroken Skin the tough dead cells that make up
  the outer layer of skin forms an effective
  barrier to prevent pathogens from entering body
  tissues.
• The more piercings or tattoos you have allows
  entryways for pathogens into your body.

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Physical Barriers

• Mucous Membranes the soft, skin-like lining of
  many parts of the body, which have cilia (tiny
  hair-like structures) and produce mucus to trap
  pathogens.
• These trapped pathogens are then expelled when
  you cough or sneeze

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Chemical Barriers

• Includes enzymes in tears and saliva, and acidic
  digestive juices, which help destroy bacteria

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Body Cells

• White blood cells (Phagocytes), which destroy
  pathogens in the bloodstream by phagocytosis, a
  process of engulfing and destroying pathogens.
• Neutrophils and macrophages are the chief types
  of phagocytes involved with phagocytosis.

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Inflammatory Response

• A reaction to tissue damage caused by injury or
  infection.
• The purpose is to prevent further tissue damage
  and stop invading pathogens

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Inflammatory Response

• Chemical mediators are released, which cause the
  blood vessels to dilate (widen) increasing blood
  flow.
• This allows fluids and phagocytes to leave the
  blood stream and enter the body tissues where
  they destroy the pathogen.
• Pus, a collection of dead white blood cells and
  damaged tissue may collect at the site of
  inflammation as a response to bacteria.

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Inflammatory Response

• Once the pathogens are killed and tissue damage
  is under control, tissue repair can begin.
• Symptoms of inflammation include heat, redness,
  and swelling.

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The Adaptive Immune System

• This includes lymphocytes, which mount specific
  attacks against particular types of pathogens.

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B Cells

• Produce antibodies, a protein that acts against a
  specific antigen.
• Each B cell is programmed to make one type of
  antibody, specific to a particular pathogen.
• Some antibodies attach to foreign antigens to
  mark them for destruction. Some destroy invading
  pathogens, and others block viruses from entering
  the body.

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T Cells

• Helper T Cells trigger the production of B
  cells and killer T cells.
• Killer T Cells stimulated to multiply by the
  presence of infected body cells, they attach to
  these cells and release toxins to destroy them.
• Suppressor T Cells coordinate the activities of
  other T cells. They turn off or suppress T
  cells when the infection has been cleared

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Memory Lymphocytes

• Your immune system actually has a memory.
• Some T cells and B cells that have been activated
  by antigens become memory cells, which circulate
  in your bloodstream and lymphatic systems.
• When memory cells recognize a former invader, the
  immune system uses antibodies and killer T cells
  to stop it.

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Immunity

• Active Immunity The immunity your body develops
  to protect you from diseases.
• Passive Immunity The immunity your body
  develops from receiving antibodies from another
  person or animal. It is short-lived, usually only
  lasting weeks to months.

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Active Immunity

• Naturally Acquired Active Immunity
• Develops when your body is exposed to antigens
  from invading pathogens.
• Artificially Acquired Active Immunity
• Develops in response to a vaccine, a preparation
  of dead or weakened pathogens that are introduced
  into the body to stimulate an immune response. In
  this way, vaccines cause your body to produce
  antibodies without actually causing the disease.

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Passive Immunity

• Natural Passive Immunity
• Occurs when antibodies pass from mother to child
  during pregnancy or while nursing.
• Artificial Passive Immunity
• Results from an injection of antibodies produced
  by an animal or a human who is immune to the
  disease.

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Vaccines

• Live-Virus Vaccines
• Made from pathogens grown under special
  laboratory conditions to make them lose most of
  their disease-causing properties.
• Although weakened, the organism can still
  stimulate the production of antibodies.
• The vaccines for measles, mumps, and rubella
  (MMR) and for chicken pox are produced this way.

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Vaccines

• Killed-Virus Vaccines
• These use inactivated pathogens.
• Even though they are dead, the organism still
  stimulates an immune response and antibodies are
  produced.
• Flu shots, the Salk vaccine for polio, and the
  vaccines for hepatitis A, rabies, cholera, and
  the plague are all made this way.

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Vaccines

• Toxoids
• These are inactivated toxins from pathogens used
  to stimulate the production of antibodies.
• Though many pathogens are not harmful to
  themselves, the toxins they produce cause
  sickness. Toxoids can be used to protect the body
  against such illnesses.
• Both tetanus and diphtheria immunizations use
  toxoids.

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Vaccines

• New Second Generation Vaccines
• These are being developed by scientists using new
  technology.
• An example is the vaccine for hepatitis B, which
  is made from genetically altered yeast cells.
• Even though it is not made from the pathogen, it
  tricks the body into producing antibodies,