unit 6 infectious diseases

Question 1

colonization

Answer 1

population established on a host
–> has to be living and multiplying

Question 2

infection

Answer 2

invasion of cells and tissues by pathogens

Question 3

acute

Answer 3

rapid onset of symptoms that ends with complete resolution or death

Question 4

chronic

Answer 4

prolonged + persistent infections that are slow to resolve or never reside

Question 5

sub-acute diseases

Answer 5

active infection without noticeable symptoms

Question 6

pathogenesis

Answer 6

process by which infection develops

Question 7

virulence

Answer 7

pathogens ability to cause damage and the severity of factors that cause damage

Question 8

carriers

Answer 8

carry disease

Question 9

reservoirs

Answer 9

where organism is naturally maintained and reproduced

Question 10

vectors

Answer 10

organism that carries disease causing agent

Question 11

pathogens vs opportunistic pathogens vs nonpathogens

Answer 11

pathogens: cause infection amongst all

opportunistic: normally commensal, but becomes pathogens

nonpathogens: incapable of causing disease

Question 12

5 stages of infection

Answer 12

1. incubation
2. prodromal
3. illness
4. decline
5. convalescence

Question 13

necessary criteria for sustaining infectious agents within a population

Answer 13

dependent on availability of susceptible individuals and degree of population infection

Question 14

outbreak

Answer 14

result from introduction of an infectious agent into an area

Question 15

epidemic

Answer 15

large abrupt outbreaks that occur over a larger population over short period of time

Question 16

pandemic

Answer 16

continent-wide or worldwide epidemics

Question 17

typical pathology of viral spread to human host

Answer 17

local infection with nonspecific symptoms –> viremia with systemic symptoms –> infection of secondary tissues –> resolution and latent infection

Question 18

mechanisms by which viruses are transmitted to humans

Answer 18

fomites (door knob), respiratory (droplets), fecal-oral, direction contact with secretions, parenteral (blood transfusion), transplacental (in utero), vectors (mechanical/biological, zoonoses

Question 19

factors that help determine severity of viral diseases

Answer 19

pathogenicity (stability, infectious dose, etc.), target tissue, and host defenses and immune status

Question 20

role of innate immunity in protecting humans against viral infections

Answer 20

direct killing of viral infected cells

Question 21

HMI in protecting against viral infections

Answer 21

AB act as opsonins or neutralizing Ab’s that prevent attachment to host cells

Question 22

CMI in protecting against viral infections

Answer 22

CD8 cytotoxic cells kills viral infected cells

Question 23

viremia

Answer 23

virus to bloodstream

Question 24

permissive tropism

Answer 24

permissiveness of cells to allow for viral replication (appropriate receptors for virus to attach)