COMMUNICABLE DISEASES

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COMMUNICABLE DISEASES
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COMMUNICABLE DISEASES

• Disease spread from one living thing to another
  or through the environment
• Pathogens (organisms) cause disease
• Infection-condition that occurs when pathogens
  enter body, multiply and damage body cells
• If body cant fight off pathogen, disease develops

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VIRUSES
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VIRUSES

• Pieces of genetic material surrounded by protein
  coat, inert outside of body, enters cell and
  takes over producing more of the virus, kill
  cells usually immune system handles many viruses,
  antibiotics dont work on them
• Common cold, influenza, viral pneumonia, viral
  hepatitis, polio, mononucleosis, measles, AIDS,
  viral meningitis, chicken pox, herpes, rabies,
  smallpox

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BACTERIA
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BACTERIA

• Single-celled microorganisms, most harmless and
  essential, some produce toxins (tetanus) kill
  cells or interfere with function, most treated
  with antibiotics
• Foodborne illness, strep throat, tuberculosis,
  diphtheria, gonorrhea, lyme disease, bacterial
  pinkeye, bacterial pneumonia, bacterial meningitis

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FUNGI

• Multi-cellular, cause diseases of skin mucous
  membranes
• Athletes foot, ringworm, yeast infection

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PROTOZOANS

• Single-celled, larger more complex than
  bacteria
• Malaria, amoebic dysentery, sleeping sickness

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RICKETTSIAS

• Resemble bacteria, act like virus invading cells,
  bite of insect transmission
• Typhus, Rocky Mountain spotted fever

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TRANSMISSION

• Direct contact-with person, animal, something in
  environment, touching, kissing, biting, sexual
  contact, sneezing/coughing on someone, through
  placenta, puncture wound
• Indirect-sneeze on object, someone else touches
  it
• Vectors-organism (i.e. tick, fly, mosquito)
• Water/food-careless handling, storage
• Airborne-sneeze/cough pathogens float in air a
  long time

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SNEEZE
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PREVENTING DISEASE

• Washing hands is most effective strategy
• Handling food properly, wash hands, keep surfaces
  clean, separate raw meat, cook food properly (hot
  enough), chill leftovers quickly
• Eat balanced diet, physical exercise, avoid
  substance use
• Avoid sharing eating utensils, grooming utensils
• Prepare/store food properly

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MORE PREVENTION

• Avoid unnecessary contact with sick people
• Take care when ill, cover mouth when
  sneezing/coughing
• Keep vaccinations current
• Abstinence from sexual activity
• Manage stress, stress weakens immune system, more
  likely to get sick

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IMMUNE SYSTEM

• Network of cells, tissues, organs and chemicals
  that fight pathogens
• Physical and chemical barriers,
• skin
• mucous membranes
• enzymes in tears
• saliva
• cilia (respiratory system)
• gastric juice

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MAJOR DEFENSE 1

• Inflammatory response (general)-reaction to
  tissue damage (injury or infection) to prevent
  further damage/halt pathogens
• Site becomes hot, swollen, red, painful, blood
  vessels expand fluid and cells leak into area
• Phagocytes-white blood cell attacks pathogen,
  engulfs it, destroys with chemicals
• Pus-collection of dead white blood cells/pathogens

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DEFENSE 2 (SPECIFIC)
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SPECIFIC DEFENSES

• The immune response
• Pathogen invades body
• Macrophage engulfs pathogen
• Macrophage digests, T cells recognize antigen
• T cell binds to antigen
• B cells bind to antigen helper T cells
• B cells divide/produce plasma cells
• Plasma cells release antibodies into blood
• Antibodies bind to antigens help other cells
  identify and destroy pathogens

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IMMUNE RESPONSE

• Immunity develops to certain pathogens
• Lymphocytes-specialized white blood cell T cells
  B cells
• Helper T cells trigger production of B cells and
  killer T cells
• Killer T cells attack destroy infected body
  cells
• Suppressor T cells coordinate other T cells, turn
  off helper T cells when infection is cleared
• B cells produce antibodies (specific)

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IMMUNITY

• Memory cells are produced and circulate, when a
  recognized pathogen enters body, antibodies and
  killer T cells act
• Active immunity-like after the measles
• Artificially acquired active immunity-vaccines
  create (some temporary)
• Passive immunity, receiving antibodies from
  another person or animal (temporary) i.e. at
  childbirth

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CARE OF IMMUNE SYSTEM

• Good health behavior
• Follow good nutritional plan
• Get plenty of rest (teens-9 hours)
• Regular physical exercise
• Dont share personal items (grooming)
• Avoid negative substances
• Avoid sexual contact (HIV)
• Keep immunizations up to date

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VACCINES

• Live-virus vaccines, laboratory grown pathogens
  (weakened) measles, mumps, rubella, chicken pox
• Killed-virus vaccines, Flu, polio, hepatitis A,
  rabies, cholera, plague
• Toxoids, inactivated toxins from pathogens,
  tetanus diphtheria
• New and second-generation vaccines, hepatitis B
• Keep vaccinations up to date

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COMMON DISEASES

• Respiratory infections, most common disease, any
  part of respiratory tract, smoking can increase
  the likelihood
• Common cold, viral, common transmission-hand to
  hand, no cure,
• Influenza, viral, airborne transmission, direct
  or indirect, can lead to pneumonia (air sacs fill
  w/pus or liquid, flu vaccines available
• Pneumonia viral or bacterial (flu and pneumonia
  on top ten list for death)
• Strep throat, bacterial, droplets spread by
  sneezing/coughing
• Tuberculosis, bacterial

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HEPATITIS

• Inflammation of the liver, caused by many things,
  causes liver damage, no cure, vaccines for A B
• Hepatitis A, spread through direct contact not
  washing hands, most recover, can cause jaundice
• Hepatitis B, more serious, bodily fluids, sexual
  intercourse common transmission, severe liver
  damage
• Hepatitis C, blood borne, share needles, liver
  damage leading cause of liver transplants

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OTHER COMMON DISEASES

• Mononucleosis, viral, attacks lymphocytes, direct
  contact, need rest
• Measles, viral, coughing sneezing, talking, no
  definite treatment, vaccine available
• Encephalitis, brain swelling, virus carried by
  mosquitoes, no treatment
• Meningitis, viral or bacterial, inflamation of
  covering of brain, antibiotics, antiviral
  medicine

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EMERGING INFECTIIONS

• Diseases on the increase, or threatening to
  increase
• AIDS, Lyme disease, malaria, tuberculosis
• Transport across borders, new disease in area
• Population movement, move to areas of disease
  (Lyme disease)
• Resistance to antibiotics
• Changes in food technology
• Agents of bioterrorism