Download Infectious disease

INFECTIOUS DISEASE
WHAT ARE INFECTIOUS DISEASES
• TINY MICROBES SUCH AS BACTERIA AND VIRUSES WHICH GET INTO YOUR BODY AND
MULTIPLY IN LARGE NUMBERS
• FORCES OF NATURE OR EVIL DEEDS
• DISCOVERED AROUND 1680 – ANTONI VAN LEEUWEHOEK
• BACTERIA, FUNGI, PROTOZOA, VIRUSES, AND PRIONS (REFERRED TO THEM AS ANIMAL-CULES)
Not a microorganism
MECHANISMS OF INFECTION
• FACTOR ONE
• VIRULENCE – THE ORGANISMS ABILITY TO CAUSE DISEASE
• FACTOR TWO
• THE NUMBER OF ORGANISMS WHICH INVADE THE BODY
• FACTOR THREE
• RESISTANCE – ABILITY TO FIGHT OFF INFECTION
INVASION
• INVASION
• INFLAMMATION – SWELLING AND REDNESS
• TOXINS
• MICROORGANISMS INVADE TISSUE AND RELEASE TOXINS
• AS BLOOD PASSES THROUGH INFECTED TISSUES THE TOXINS ARE PICKED UP AND DISTRIBUTED
THROUGHOUT THE BODY
• MO TRAVELS TO A SPECIFIC AREA OF BODY (CNS)……ZIKA VIRUS
RESISTANCE TO INFECTION
• IMMUNE SYSTEM
• WHITE BLOOD CELLS
• MACROPHAGES
• LYMPHOID TISSUE
• TWO FUNCTIONS
• ENGULFING AND DESTROYING AGENTS
• PRODUCING ANTIBODIES
RESISTANCE
• NEUTROPHILS – TYPE OF WBC
• MOBILE UNITS FORMED IN BONE MARROW
• PROVIDE RAPID AND POTENT DEFENSE
• SURROUND AND KILL MO
RESISTANCE
• MACROPHAGES
• LARGE SLOW MOVING
• RESIDE IN BONE MARROW, LIVER, SPLEEN,
AND BLOOD
• KILL ORGANISMS SURVIVING THE
NEUTROPHILS
RESISTANCE
• MACROPHAGES
• INFLAMMATION
• MACROPHAGES WITH THE WBC WILL KILL
OFF INVADING MO
• PUS – RESULT OF THE DEAD MACROPHAGES
AND WBC
LYMPHOCYTES
Attack organisms directly
T CELL
Form antibodies that
attach to the surface of
MO marking it for
destruction
B CELL
TYPES OF INFECTIOUS AGENTS
BACTERIA
VIRUSES
• SIMPLE, ONE-CELLED ORGANISMS
• MOST NUMEROUS LIFE FORM – NOT A MO
• MOST ARE HARMLESS
• NEED A HOST TO SURVIVE
• PASS BODY DEFENSES OR NORMAL
DEFENSES ARE WEAKENED
• PATHOGENIC ALMOST ALWAYS CAUSE
INFECTION
• EITHER DNA OR RNA
• TAKE OVER HOST CONTROL CENTERS IN THE
NUCLEUS
• MAKE SPECIAL PROTEINS CAUSING
SYMPTOMS & REPLICATE THEMSELVES
VIRUSES
• 1930’S – ELECTRON MICROSCOPE HELPED TO BETTER UNDERSTAND SHAPE AND COMPLEXITY
• SPREAD THROUGH
• DIRECT CONTACT
• INDIRECT CONTACT
• INSECT OR ANIMAL BITE
• INFLUENZA VIRUS
TYPES OF INFECTIOUS AGENTS
FUNGI
PARASITES
• NON-GREEN PLANTLIKE
• LIVE AND FEED ON ANOTHER ORGANISM
• CAUSE ABOUT 30 DISEASES – MYCOSES
• ENDOPARASITES – PROTOZOANS THAT LIVE
WITHIN THE BODY (TAPEWORM)
• EVOLVE SLOWLY
• SKIN, HAIR, FINGERNAILS
• ECTOPARASITES – LIVE ON BODY’S SURFACE
(TICKS, FLEAS, LICE, WORMS)
DISEASE CLASSIFICATION
• TYPE OF ORGANISM CAUSING THE DISEASE
• ORGAN SYSTEM THEY INFECT
• SETTING IN WHICH THEY OCCUR
• MOST COMMON ENCOUNTERED INVOLVE
• SKIN
• RESPIRATORY SYSTEM
• GASTROINTESTINAL
• UROGENITAL
PREVENTION & TREATMENT
• REDUCE EXPOSURE TO INFECTIOUS ORGANISMS
• MAINTAINING BODY’S NATURAL DEFENSE SYSTEM
• USING IMMUNIZATIONS
• BETTER NUTRITION AND SANITATION