Infectious Dis.

Question 1

Infectious Dis

Answer 1

transmissible/ communicable dis.s

-w/ characteristic symptoms+ presence and growth pathogenic bio agents in host organisms.

Question 2

Carrier

Answer 2

asymptomatic

-only dis. in hosts that b/cm ill after contact with asymptomatic ind.

Question 3

Colonization

Answer 3

=required to devo ill

-presence of organisms NOT= to infectious dis.

Question 4

Infectious Dis. Interest: Pre-antibiotics

Answer 4

^mortality Rs (poverty+ war) w/ little could do about dis.s

• inds D b/c of infection not wounds» experimental medi= common
• Greeks, Egyptians, Romans= forerunners o mod physicians

Question 5

Infectious Dis. Interest: antibiotics

Answer 5

1950s= widespread use» ^devo+ improved treatment

-interest decreased (all dis.s would be wiped out)

Question 6

Infectious Dis. Interest: 1980s

Answer 6

dramatic ^in infectious dis.s

Question 7

Infectious Dis. Interest: 1990s

Answer 7

Infectious dis b/cm 1 o top 5 killers in US

AIDS Ds mostly due to 2ndary bacterial infects

Question 8

Why Infect dis increase?

Answer 8

1. older pop
2. ^ o immuno-compromised pop. (organ trans, cancer therapy, invasive surgery)
3. antibiotic resistence
4. emerging infect dis.s

Question 9

Emergence of Infect Dis: Ancient Hist

Answer 9

-Bact +Archaea=» endosymbionts in eukaryotic Cs
root nodules= N2 fixation
colonizing GI tract» nutrition, protective nature
-Bact +protozoan interaxns&raquo_space; drivning force in infect dis.s (protozoa similar to phagocytic Cs)
-domesticated anis ^

Question 10

Why MicroOrg infect host: Nutrition and Safety

Answer 10

• Host= stable, nutrient rich source, ideal for growth

- mjr role/ selective pressure in host Evo

Question 11

emerging dis.

Answer 11

infect dis. incidences have ^ in last 20yrs

newly IDd or new strains (SARS, AIDS)

Question 12

reemerging dis.s

Answer 12

known dis.s that have come back in diff form or location

West Nile, Dengue, TB

Question 13

Why ^ in emerging/ reemerging dis.s?

Answer 13

microOrgs easier to detect
some submerge +reemerge over time
dis. patterns constantly changing

Question 14

Mechs for emerging and reemergence

Answer 14

• microbial adaptation (genetic drift o Influenza A)
• changing hu. susceptibility (mass immunocompromised pop> HIV/AIDS)
• Climate and weather (zoonotic vectors w/ ^range/ new locations)
• varying hu. demographics+ trade (e.g. SARS)
• economy devo> food antibiotics=> resistance
• poverty, class, culture=> who mo susceptible
• War and famine
• bioterrorism

Question 15

Genetic Drift

Answer 15

small, random genetic changes in small/ iso pop» new variant overtaking original pop

Question 16

Types of emerging/ reemerging infect dis.s

Answer 16

new-new dis.
new-old dis
old-new dis
old-old dis.

Question 17

New-new dis

Answer 17

• caused by newly discovered org (Bact. species)

- Difficult- know for sure b/c o poor historical records o infectious diseases

Question 18

New-old dis

Answer 18

-caused by newly recognized pathogen, but org has been known

Question 19

Old-new dis.

Answer 19

-old dis. w/ known causes thought to have been elim» reappeared

Question 20

Old-old dis.

Answer 20

-old dis. w/ known causes now being recog by public and media.

Question 21

Lyme dis

Answer 21

new-new dis

• Borrelia burgdorferi (Spirochete)
• gram -
• thin helical corkscrew
• tics on deer and mice= reservoirs

Question 22

Why increase in lyme dis

Answer 22

• deer pop^ (reforestation, hunting limits, decrease in predators)
• hu. pop^ (move into/ closer to deer habitat)» hu. inserted into tic-mouse-deer cycle
• DIS. ONLY IN HU.S

Question 23

Legionellosis (Legionnaire’s disease)

Answer 23

new-new dis

• Legionella pneumophila
• H2O pathogen> trans thru aerosols (AC units, H2O distribution)
• gram - (nds ^Fe)
• rod biofilm forming

Question 24

epidemiology

Answer 24

study o factors affecting health+ illness o pops
(occurrence, distribution and determinants)=> medi interventions+ preventative measures
-tracking and gathering info

Question 25

TB

Answer 25

old-new dis - Mycobacterium tuberculosis - gram + - respiratory trans=> waxy tubercles in lungs - recent comeback w/ physicians unable to ID dis

Question 26

Cholera

Answer 26

old-new dis (S Am.) - Vibrio cholerae - gram - - comma-shaped rod - trans via sewage contaminated H2O - gastrointestinal infect of enterotoxin - 7 mjr pandemics

Question 27

Epidemic

Answer 27

when new cases o a dis, in given hu pop, + during given period, exceed what "expected," based on recent experience

Question 28

Pandemic

Answer 28

an epidemic o infect dis that spread through hu pops across a large region

Question 29

Reasons for reemergence

Answer 29

gene trans- recent in old strain - Ecological condts prevent emergence>> unkwn 20thc factor allowed resurface (e.g. farming practs) - acquire new traits (antibiotic resistance) (e.g. MRSA)

Question 30

Chlamydia trachomatis

Answer 30

old-old dis - gram - - minimal genome> obligate intraC pathogen? - generally asymptomatic - most common infect reported in USA

Question 31

Why ^ in re/ emerging dis.s?

Answer 31

^ awareness/ detection - mod medi (chemotherapy, longer life-span>> immunocomp elderly, crowding)>> opportunistic pathogens - cul diffs of accepted B

Question 32

Opportunistic pathogen: Burkholderia cepacia

Answer 32

pneunomia | -mouthwash= source (not respiration equipment)

Question 33

Types of Infect Dis.

Answer 33

``` water-borne food-borne hospital acquired antibiotic resistance microbiota shift dis.s bioterrorism ```

Question 34

Contributing factors o infect dis. events

Answer 34

``` ease of travel pop^ pop displacement agri changing socio-economic structures international conflicts pollution/ global warming ```

Question 35

Water-borne dis.s

Answer 35

precious resource - single source may serve numerous ppl>> potential of many ppl to get sick - precip and extreme weather associated w/ water-borne outbreaks - flooding= most freq (Diarrhea-­‐associated dis.s, cholera, typhoid, hepatitis (jaundice),+ leptospirosis)