INFECTIOUS DISEASES

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INFECTIOUSDISEASES
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Terminology

• Infection
• Invasion of body by disease causing organism and
  the bodys reaction to its presence
• Antigen
• Foreign invader
• Stimulates a response from the immune system
• Antibody
• Chemical compound made by immune system to
  destroy antigens and toxins
• Toxins
• Chemicals released by the antigen

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Infectious Agents

• Bacteria
• One celled organism
• Virus
• Smallest common pathogen
• Fungi
• Plantlike microorganism
• Rickettsia
• Virus like organism that requires a host
• Protozoa
• Simplest animal organism, one celled
• Parasitic worms
• Many celled organism ie leeches, tapeworms

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• Agent
• Disease causing agent
• Reservoir
• Humans, animals, soil
• Portal of exit
• Respiratory system, blood, digestive system

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• Mode of transmission
• Direct contact
• Physical contact
• Indirect contact
• Handwashing between patients
• Droplet contact
• sneeze
• Vector borne
• insects

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Chain of Infection

• Portal of entry
• Digestive, respiratory, reproductive system
• The new host

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Stages of Infection

• Incubation period
• Organism invades and multiplies
• Prodromal period
• General symptoms
• Clinical disease
• Illness at its peak with specific symptoms
• Decline stage
• Symptoms subside
• Recovery period
• Still contagious

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Immunizations/Vaccines

• Diptheria
• Inflammation of the throat
• Whooping cough
• Bacterial infection
• Hepatitis B
• Viral infection affecting liver
• Haemophilius influenzae type B
• Bacterial infection affecting heart and brain
• Tetanus
• Bacterial infection of central nervous system

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Immunizations/Vaccines

• Rubella
• German measles
• Measles
• Viral infection
• Polio
• Viral infection causing paralysis
• Mumps
• Viral infection of salivary glands
• Chicken pox
• Viral infection with rash

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Food Poisoning

• Sickens 76 million/yr, kills 5000
• Salmonella poisoning
• Poultry
• Trichinosis
• Pork
• Listeria
• Cheese, milk, yogurt
• E-coli
• meat
• Botulism
• Canned goods

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Food Poisoning

• Avoiding food poisoning
• Wash fruits and veggies
• Thaw chicken in refrigerator
• Wash hands after handling poultry
• Thoroughly cook chicken, eggs, meats
• Refrigerate foods quickly

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Toxins

• Bacteria can release toxins near cells to destroy
  them
• Some toxins are very powerful
• ¼ teaspoon to toxin released by tetanus organism
  is strong enough to kill 10,000 people

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Antibiotics

• Group of drugs that destroy or inhibit bacteria
• Not effective against viruses
• Rise of drug resistant bacteria
• 95 of hospitals have vancomycin resistant
  bacteria
• 40 of streptococcal pneumonia is resistant to
  antibiotics

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Colds

• Acute rhinitis
• Approx 200 know rhinoviruses
• Can be transmitted by droplets (sneezing or
  coughing)
• Most common transmission hand contact
• To prevent transmission wash hands frequently
• Keep you hands away from your nose
• Incubation period 18-24 hours

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Influenza/Flu

• Flu epidemic of 1918-1919
• Killed 50 million people in 18 months
• Virus very contagious in first 3 days
• Kills 40,000 people/yr and hospitalizes
  300,000/yr
• Flu vaccine

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Tuberculosis

• Bacterial infection of lungs
• chronic cough, weight loss, death
• Most commonly spread by coughing
• Antibiotic resistant strain in US

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Pneumonia

• Respiratory infection
• Can be caused by bacterial, viral, parasitic or
  fungal causes
• Elderly die from pneumonia

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Mononucleosis

• Spread by oral contact, blood transfusions
• 15-25 is the usual age group
• Caused by Epstein-Barr virus
• Fever, sore throat, nausea, chills, rash enlarged
  spleen
• Mono spot
• Blood test
• Life long immunity
• Bed rest
• Avoid contact sports

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Bacterial Meningitis

• Infection of membranes surrounding brain and
  spinal cord
• High fever, severe headache, stiff neck, nausea,
  vomiting, rash, flu like symptoms
• Kills approx 300 of the 3000 who get sick each yr
  in the US
• Higher rates in college students
• Vaccination
• Given at 11-12 year old check up
• Entering high school students
• Entering college students
• Protects for 10 years

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Lyme Disease

• Bacterial disease from infected deer ticks
• Symptoms in 30 days, small bumps around circular
  red rash with flu symptoms
• Later stages lead to disorders of nervous system,
  heart, chronic arthritis
• Treated with antibiotics
• Protect yourself from ticks while outdoors
• Wear long pants and long sleeve shirts
• Tuck your pants into your socks
• Check yourself and your pets for ticks

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Lyme Disease
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Toxic Shock Syndrome

• Widespread infection related to tampons
• Develop shock
• Tampons should be changed every 4 hours, never
  longer then 8 hours

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Hepatitis

• Viral inflammation of the liver
• Type A, B, C, D, E
• Type A
• Related to poor sanitation, contaminated foods
• Contaminated vegetables from Mexico implicated in
  many outbreaks of hepatitis A
• Found in developing countries
• Vaccine is available

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Hepatitis

• Type B
• Related to sexual contact, blood transfusions,
  IVDA, tattooing, body piercing
• Symptoms include jaundice, headache, pain over
  liver
• If a coma develops only 10-20 survive
• Vaccine available, must be given before
  kindergarten and to health care workers

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Hepatitis

• Type C
• Spread same way as type B
• Kills 12,000/yr in US
• 2.7 million carry the hepatitis C virus
• 90 IVDA carry the hepatitis C virus

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Hepatitis

• Type D
• Found in people with type B
• Difficult to treat
• Type E
• Associated with water contamination
• Rarely seen in US

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SARS

• Severe Acute Respiratory Syndrome
• Atypical pneumonia
• Caused by a virus
• First found in China
• Extremely contagious

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Avian Bird Flu

• H5N1 virus
• Found initially in Asian birds and has now spread
  to Europe
• Concerned that it may mutate and be easily
  transmitted to humans
• So far it has killed about 100 people world wide
• Health officials fear a world wide epidemic
  killing millions