Microbiology Lecture 20, 21, 22, 23

Front 1

The most common bacterial disease

Back 1

Dental decay

Front 2

Three diseases common in the developing countries at the beginning of the 20th century:

Back 2

1. pneumonia
2. diarrheal disease
3. tuberculosis

Front 3

Pneumonia and tuberculosis are known as __________ respiratory infections (ARI)

Back 3

Acute

Front 4

The Three Modes of Transmission of Infectious diseases

Back 4

1. Airborne (transmission of diseases)
2. Direct contact (transmission of diseases)
3. Sexually transmitted diseases

Front 5

ARI stands for:

Back 5

Acute Respiratory Infection

Front 6

Airborne Transmission of Disease:

Aerosols are very common and mainly impact what?

Back 6

The respiratory system

Front 7

___________ are important vehicles for person-to-person transmission. They can be transmitted through sneezing, coughing, and shouting.

Back 7

Aerosols

Front 8

The leading cause of death among infectious disease?

Back 8

Acute Respiratory Infections

Front 9

Micyobacterium tuberculosis (Mtb) is an airborne disease that infects one person to another person.

True/False

Back 9

True

Front 10

Mycobacterium tuberculosis was isolated by Robert __________ in 1882, and is gram-____________. It is an acid ____________ (mycolic acid) bacillus.

Back 10

Koch; gram positive; acid fast

Front 11

Mycobacterium tuberculosis is a reemerging disease because it is becoming increasingly _______________ to drugs.

Back 11

resistant

Reemerging disease because the antibiotics we keep using are no longer effective because they are becoming resistance to it

Front 12

2 ways to become directly infected by an airborne disease like Tuberculosis through droplets?

Back 12

coughing, sneezing

Front 13

Tuberculosis attacks our ______________ cells and lives inside of our macrophages.

Back 13

immune cells

Front 14

What are the 4 steps of Tuberculosis (TB) Infection?

Back 14

1) Exposure to TB (from an infected individuals cough/sneeze)
2) Infection
3) Immune system adjusts right away to eliminate it

- Innate Response (fast, not that specific): Dendritic Cell eliminates as much of the bacteria as possible

- Adaptive Response (slow, much more specific): T-Cell eliminates bacteria as much as possible

4. Immune system controls the replication of bacteria until it is Latent/dormant (ie. walled off by immune cells so that it is no long infectious and the person isn't contagious)


- Macrophages recognize foreign TB bacteria, engulf it, and try to digest it - if a TB bacterium isn't digested by lysosyme, then it remains engulfed by macrophage

- Macrophages start to cluster inside your lungs
- Granuloma: collection of macrophages due to immune response and inflammation; forms when the immune system attempts to wall off the TB foreign substances but is unable to eliminate/digest it
_________________________________________________________
- TB can be kept latent/dormant/contained for the rest of your life IF it isn't at one point reactivated spontaneously

5) If it becomes active - TB bacterium multiplies inside macrophages and kills it – spreads into lungs, bone, bloodstream, etc – at that point it’s highly contagious and you die from it

Front 15

Granuloma is the collection of _______________ due to immune response and inflammation; forms when the immune system attempts to ________________but is unable to eliminate/digest it

Back 15

macrophages; wall off TB foreign substances

Front 16

Tuberculosis TB can be latent or active infection.

True/False

Back 16

True

Front 17

Which of the 2 types of Tuberculosis (TB) infection is this:

TB bacteria is localized and appears to end. Immune system responds, and a solid granuloma is present.

Back 17

Latent TB infection

Front 18

A TB test comes back positive (measures the host immune response) - this doesn't indicate active disease, only exposure in the past. However, the individual can develop TB again. This is called a ______________ infection.

Back 18

Post primary infection - when a new bug reinfects that individual or the dormant bacteria in lung macrophages is reactivated.

Front 19

Which of the 2 types of Tuberculosis (TB) infection is this:

Viable TB bacteria is inhaled, and settles in the lungs to grow. The host's immune system responds - results in tubercles-aggregates of activated macrophage. Bugs grown here, acute infection, destruction of lung, spreads, death.

Back 19

Active TB infection

Front 20

Postprimary TB infection

Back 20

TB is no longer dormant but is reactivated

Front 21

The major steps from infection to disease in TB and current and future accination strategies against TB

Back 21

Steps from infection to disease in TB
1) inhation of Mtb
2) T cell stimulation
3) Latent infection (solid granuloma forms) without clinical disease - multifunctional T cells

4) Active TB (oh no) - pathogen breaks out of granuloma
5) Mtb disseminates/is highly contagious

1) Vaccination BEFORE exposure

Front 22

Tuberculosis (TB) treatment:

Standard 1st Line drugs (ie. Isoniazid, Rifampin) do what?

Back 22

inhibit cell wall synthesis, RNA synthesis, and plasma membrane integrity

Front 23

Tuberculosis (TB) treatment:

Standard 2nd Line drugs (ie. thiamides, aminoglycosides) do what?

(Will use this if 1st Line drugs doesn't work)

Back 23

inhibit cell wall and protein synthesis

Front 24

Viruses such as measles, mumps, rubella, chickenpox, common colds, influnza, etc are all considered what kind of Transmission of Disease?

Back 24

Airborne Transmission of Disease

Front 25

What type of diseases are known to have pathogens that spread primarily by direct contact with infected person, or contact with blood or excreta from infected person and entry through wounds? It mainly impacts skin or underlying tissue.

Many of the respiratory diseases can be spread this way

Back 25

Direct contact diseases

Front 26

Clostridium perfringens (gas) and Mycobacterium leprae are examples of _________ _________ diseases.

Both can spread from person to person through coming in contact with blood or excrement – the receiving person has some sort of wound that the disease can enter through

Back 26

Direct contact diseases

Front 27

Direct Contact Diseases:

Staphylococcus commonly infects skin and wounds and cause what?

Back 27

Acne, boils, impetigo, meningitis, toxic shock syndrome

Front 28

Direct Contact Diseases:

S. aureus strains (causing disease) are gram ___________ and have 4 virulence factors: hemolysins, ___________, ___________, ___________.

Back 28

1. hemolysins - to lyse open red blood cells
2. exotoxins
3. adhesins - binds to receptor sites of certain cells to invade
4. invasins - protein produced to ruffle the cell membrane and disrupt the cytoplasm so that the microbe can sink through and be engulfed by the cell

Front 29

Direct Contact Diseases:

A) Clostridium perfringens – get under tissue and grow and produce what?

B) Mycobacterium leprae – can cause damage to _________ _________ system – finger tips and toes can go away

Back 29

A) gases and a potent exotoxin that kills the tissue

B) peripheral nervous system

Front 30

MRSA (Methicillin-resistant S. aureus) is a nosocomial infection.

A nosocomial infection is what?

Back 30

It is healthcare associated; it is an infection acquired in a hospital; can spread from healthcare personnell who are carriers of the drug resistant strains but show no symptoms

Front 31

Direct Contact Diseases:

_______________ is gram positive and can cause a wide range of disease conditions: meningitis, pneumonia, sore throats, otitis media, caries, necrotizing, fasciitis, etc.. It is flesh eating (HINT: STRIPS you of your flesh), secrete toxins (hemolysins) enzymes (that destroy the tissue), virulence factors.

Like S. pyogenes.

Back 31

Streptococci

Front 32

What type of Transmission of Disease is this:

Variety of microbes can cause it – range from bacteria to fungi. Most of them are found in body fluids – exchanged through sexual activity. Colonize the genitourinary tract. Most are controllable and curable. Once they cause damage, it’s a big problem – can cause cancer, birth defects, syphilis (causes degenerative nerve disease)

Gonorrhea caused by - Neisseria gonorrhoeae
AIDS caused by - HIV virus
Gental herpes caused by - herpes virus
Chlamydia caused by - Chlamidyia trachomatis

Back 32

Sexually transmitted diseases

Front 33

Syphilis is a ___________ transmitted disease, is gram____________, and shaped like a spirochete.

Back 33

sexually; gram negative

Front 34

Syphilis uses __________ to adhere to receptors on host cell and penetrates the host cell membrane through ___________ motility to enter the blood stream.

Back 34

adhesins; corkscrew motility

Adhesin proteins that bind to receptors of cell; T pallidum docks on the host cell and cork screw it’s way into the cell and cause damage; they may enter the blood stream at this point.

Front 35

Define the 3 main stages of Syphilis (primary syphilis, secondary syphilis, and tertiary syphilis)

Back 35

Primary - localized infection. T. pallidum multiplies at the site of entry and a chancer lesion/open sore forms; bug can spread around the body

Secondary - you get a rash due to the immune system responding to the chancre/open sore regions (hypersensitive reaction)

Tertiary - mild infections on skin bone to fatal infections of heart or central nervous system (can lead to blindness, shuffle walk, and insanity)

Front 36

What is the etiological agent (causative agent) of Syphilis?

Back 36

T. pallidum (Treponema pallidum)