BACTERIAL PATHOGENESIS 1

Question 1

what is the major threat related to bacterial pathogens?

Answer 1

antimicrobial resistance

Question 2

what are two modern big bacterial killers?

Answer 2

tuberculosis and pneumonia

Question 3

how was the bacterial cause of ulcers determined?

Answer 3

people thought that ulcers were caused by stress or spicy food
dr marshall knew that it was caused by infection, but people were skeptical
attempts to culture the bacteria fro ulcers were unsuccessful
dr marshall drank the cultures and got ulcers
he treated himself and got a nobel prize
the bacteria is Helicobacter

Question 4

characteristics of Helicobacter pylori

Answer 4

Question 5

how do you define a pathogen with Koch’s postulates?

Answer 5

Question 6

what are some caveats of koch’s postulates?

Answer 6

Question 7

what is an infection

Answer 7

when pathogen becomes established in the body

Question 8

what is a disease?

Answer 8

infection which produces signs and symptoms

Question 9

what is a symptom vs a sign?

Answer 9

Question 10

what is asymptomatic carriage?

Answer 10

infection without disease

Question 11

how does Pseudomonas aeruginosa infect people with cystic fibrosis?

Answer 11

Question 12

what is a secondary infection?

Answer 12

an infection that develops in an individual who is already infected with a different pathogen
example: tuberculosis kills people with HIV at more than 50%

Question 13

how does microbiome impact susceptibility?

Answer 13

gut microbiome protects us from potentially harmful bacteria
when people are treated with antibiotics, you kill the good bacteria and you get a blood of the bad bacteria
an example of this is C. difficile infection following antibiotic treatment

Question 14

what are the required steps of pathogenesis of bacterial diseases?

Answer 14

Question 15

how do bacteria maintain a reservoir?

Answer 15

the reservoirs are specific for each pathogen

Question 16

what are some common reservoirs for human pathogens?

Answer 16

Question 17

who is typhoid mary

Answer 17

Question 18

what are two methods of transport of pathogen to the host?

Answer 18

direct or indirect

Question 19

what are methods of direct transport of the bacterial pathogen to the host?

Answer 19

droplet= short range, short lived
airborne=longer lived, suspended in the air

Question 20

what are methods of indirect transport of the bacterial pathogen to the host?

Answer 20

Question 21

how do bacteria carry out adherence/colonization/invasion?

Answer 21

Question 22

what are types of bacteria adhesins?

Answer 22

Question 23

what do adhesins do?

Answer 23

Question 24

how can 1 amino acid in receptors make all the difference

Answer 24

Question 25

how can invasion of bacterial pathogen be an active penetration into host cell

Answer 25

salmonella loves to live inside host cell type 3 secretion system: injects bacterial proteins into host cell zombifies actin cytoskeleton actin rearranges and brings salmonella inside the host cell

Question 26

how can invasion of bacterial pathogen be an active penetration between host cells

Answer 26

tight junctions are relatively impenetrable, but bacteria have ways to chew through those junctions to move between cells

Question 27

how can invasion of the bacterial pathogen be passive?

Answer 27

Question 28

how do bacteria multiply/complete their life cycle in the host

Answer 28

suitable environment varies a lot from pathogen to pathogen intracellular/extracellular pathogens sme bacteria invade specific cells and have adapted strategies to live inside

Question 29

how do bacteria evade host defenses?

Answer 29

bacteria must have mechanisms to resist hose defenses: complement system, phagocytosis and specific immune responses bacteria have ways of neutralizing ROS

Question 30

what is the bacterial capsule?

Answer 30

composed of chemicals not recognised as foreign, slippery and difficult for phagocytes to engulf

Question 31

how do bacteria leave the host?

Answer 31