The organism leaves your body: Two main Question you ask are:

How does the organism exit? (Possibilities incelude bloo, fece, saliva.)

When doe the organism exit? (sometimet he disease can leave you body before you even realize there is a problem. Ex. AIDS.)

1. Fingers

2. Flies

3. Fomites

4. Food

Two additions include Phlegm and Fun 

1. Nasal Secretions have mucous that can pass on Streptococci (when you pick nose)

2. Saliva from oral secretions can pass on staphylococci (when brushing teeth or wiping drool)

3. Open sores (When you touch pimples that you may have popped and then touch other areas you can pass on Staph. and MRSA)

4. Feces (When you forget to wash your hands after going to the bathroom you can pass on E-coli, Salmonella)

Two Pathways of Feces:

Feces to fingers to mouth

Feces to fingers fro food to mouth 

What does the term flies refer to?

Give examples.

Give examples of passive biological vectors.

(Flies) 

Flies land on dog feces and pick up organisms and then pass on the organism to food.

This passive method of transmission is not as  dangerous as active because as the organism is being transferred it is decreasing in virility because it is exposed to the environment the whole time. 

Give example of Active Biological Vectors.

(AKA. Reservoirs of infection)

Flies 

Can inanimate objects be reservoirs of infectionas well?

What would they be called? 

Yes, as in th ecase of soil, which can harbor the growth of athlete's foot and anthax, and pass the disease on to humans. Also th eGanges River in Indai harbors the growth of cholera in the waters.

Most inanimate objects are refered o as sources. 

Abscence of Duffy factor prevents attachment of malaria to RBC.

How long do the microaerosols created by the following stay in the air?

Sneezing

Coughing

Talking 

Sneezing: up to one hour

Coughing about a half hour

Talking for six minutes 

Nonpathogenic: 94-96%

Pathogenic: 4-6% 

1. Eliminate the Reservoirs

Example is the spread of malaria from mosquitoes so you use insecticides to kill them off.

2. Break the link in transmission

Example Feces can spread E. Coli and Samlmonell so you wash yor hands to break the link.

3. Immunizing Biologics (vaccines)

Tetanus is everwhere so you vaccinate everyone so it becomes ineffective

TB, Haemophilus, and Pneumoniae

Viral: Flu, Chicken flu/bird flu

German Measles (Rubella)

Normal Measles (Rubeola) 

E. Coli,

Salmonella (causes typhoid and food poisoning), Shigella (causes dysentary),

Cholera (loss of fluids),

Hepatits A (fece spread), Polio (CDC recommends the disuse of oral vaccines for this b/c it becomes more pathogenic when it leave the body via feces.)

Syphilis (Treponema pallidum), Gonorrhea (Neisseria gonorrhoeae), Clamydia (Clamydia trachomatis)

Viruses? AIDS, Herpes

Streptococci Staphylococci

UTI (toilet paper with improper wiping) 

STORCH

S-Syphilis-may not even know the baby has it

T-Toxoplasmosis-transferred from cat feces  (protozoal infection) Cause mental retardation/death

O-Other-AIDS, Hepatitis B, Clamydia (all of these can cause the Blood Brain Barrier)

R-Rubella-German Measles

C-Cytomegalovirus-can be deadly to unborn babies in placenta

H-Herpes simplex I and II-I = Boils, II=STD 

Chicken pox measles, mumps, etc.

1-3 weeks

Mycobacterium tuberculosis causes tuberculosis and has an incubation bperiod of 6 months.

Mycobacterium leprae causes leprosy and it has an incubation period of 2-5 years and is also rarely observed to be 40 years.

Invasiveness

Toxogenicity 

Describe the virulence of the following:

1. Syphilis

2. Tetanus

3. Streptococcus pyogenes 

1. Very Invasive, but not toxic (Syphilis)

2. Not invasive but highly toxic (Tetanus)

3. Very invasive and toxic (Streptococcus pyogenes)  

Acute 

Quick, short onset lasts a short time.

Examples include flu, cold, Hepatits A. 

Slow, long onset, long incubation period, lasts long time.

Examples:

AIDS- not an automatic death sentence, just a chronic infection as long as drugs can be afforded.

Leprosy

TB - treatment for 6-24 months

Hepatitis B and C 

Affects the whole body

Similar infections - syphilis (STD, can spread throughout the body), Lyme Diseas (tick bite, bulls eye ring, spreads throughout entire body) 

• •  confined to one area
  • boil (pimples) caused by staphylococcus aureus
  • TB localized to lung when first transmitted—primary TB is pulmonary TB, extrapulmonary TB is spread throughout the entire body
  • Tetanus

once local, it then spreads to other parts of the body

•  
  • boils – staph can spread

•  
  • TB can leave your lungs to secondary TB or extra pulmonary

• septicemia – pathogenic organisms in your blood
  • bacterenemia – bacteria in your blood
  • virunemia – viruses in your blood (HIV positive)

• Toxemia – any organism that can produce a toxin, such as tetanus and diphtheria (toxins damage heart, and results in death), toxins in blood!

• Pyemia – pus (white bld cells called neutrophils) producing (pyogenic) organisms in your blood
  • Staphylococcus, streptococcus

• Sapremia – saprophytes growing in you (they live off the dead materials (tissues) inside of you—live host
  • Sometimes a doctor may fail to remove all of the placenta after childbirth, so the mother can get a saprophytic infection
  • Gas gangrene—frostbitten, dead tissue, grows saprophytes

Hyaluronidase

a.       Part of our “cement” (hyaluronic acid)

b.      Organism can move between cells and therefore spread because they’re able to breakdown the “cement”

c.       Enzyme that breaks down hyaluronic acid

Give an example of a bacteria with Hyaluronidase?

streptococcus pyogenes—causes strep throat, and many others, causes tissue death-nephrotizing fascitis, kills flesh by destroying oxygen and rotting tissue

clostridium perforinges:  in intestinal tract, Gram positive rod, anaerobic, can spread during surgery, cancer, accident, etc.—can produce gas gangrene (tissue dies—rots in place)

Proteolyic enzyme

Breaks down the protein collagen

Found in connective tissue 

1.      Lecithinase: phospholipid

a.       Breaks down lecithin (found in cell membranes, phospholipids)

b.      Destroys cell membranes, causing cells to burst and die, especially RedBldCell’s because unnucleated and therefore can’t do repairs

c.       Hemolysin—toxin that destroys RBC

                                                                           i.      Can do 2 things

1.      cause anemia

2.      decrease amount of oxygen to cells (anoxia/hypnoxia)

2.      Streptolysins

1.      Streptolysins

a.       Hemolysin

                                                                           i.      Anemia

                                                                         ii.      Anoxia

b.      Made by streptococci

c.       Streptococcus pyogenes is capable (why serious toxin)

Streptokinase

Staphylokinase

Dissolves fibrin (involved in clots) 

Staphylococci gets into hair follicle with WBC’s (pus) which are trying to kill staph which is actually killing WBC which then makes clot (boil)