disease list

Question 1

yersinia pestis

Answer 1

• causes plague
  bubonic plague - first bite of flea and org move to
  lymph
  septicemic plague - then org move blood stream
  pneumonic plague - last highly infectious, spread by
  airborne drop
• has lots virulence fact inhibit phagocytosis

Question 2

upper respiratory infection

Answer 2

• streptococcus pyogenes (strep throat and scarlet fever)
• corynebacterium diphtheria (diphtheria)

Question 3

streptococcus pyogenes

Answer 3

• streptococci morphology
• gram positive

strep throat(streptococcal pharyngitis)
- resistant to phagocytosis; streptokinases lyse
clot; streptolysins = cytotoxic

scarlet fever
- erythrogenic toxin prod by lysogenized S.
pyogenes
- pink - red rash and fever

Question 4

corynebacterium diphtheria

Answer 4

• aerobic
• gram pos rod
• pleomorphic morphology

diphtheria
- sore throat and fever; spread = droplet
- form pseudomembrane (tough gray membrane),
restrict air flow
- produce toxin to interfere w protein synthesis
- DTaP vaccine

Question 5

lower respiratory tract infection

Answer 5

• streptococcus pneumoniae (pneumonia)
• legionella pneumophila (legionnaires disease)
• bordetella pertussis (whooping cough/pertussis)

Question 6

bordetella pertussis

Answer 6

• aerobic
• gram neg, coccobacillus
• virulence factor = capsule and toxin

Pertussis(whooping cough)
- inhibit ciliated cells in trachea and kill w/ tracheal cytotoxin
- pertussis toxin = enter blood = sym of dis
catarrhal stage - like common cold
paroxysmal stage - violent coughing; gasping for
air; 1-6 weeks
convalescence stage - months
-tdap

Question 7

streptococcus pneumonia

Answer 7

• streptococcus morphology
• gram pos, alpha hemolytic
• virulence factor = capsule prevent phagocytosis

pneumonia
- disease not specific infection(caused by many)
- typical secondary infection
- spread airborne droplet
- fluid build up in aveolar and bronci
- can spread to bloodstream and brain(meningitis)

Question 8

legionella pneumophila

Answer 8

• gram neg, no capsule, aerobic bacillus w one
  flagellum

legionnaire’s disease - form atypical pneumonia(2-9%)
- found fresh water; facultative intracellul-ar
parasite(use amoebae in envirn)
- invade and rep via inasins
- human infection = inhalation of aerosols fr
cooling towers, ac and hot tubs
- cough, short breath, high fever, muscle pain, headache, nausea and vomit
- 10% die

Question 9

digestive system infection

Answer 9

• streptococcus mutans (plaque)

Question 10

streptococcus mutans

Answer 10

• gram pos, alpha hemolytic
• primary agent in dental caries
• metabolize diff types of sugars; tolerate acidity;
  synthesize dextran
• biofilm and plaque formation

Question 11

GI tract infections

Answer 11

• rotaviruses (dehydration)
• shigella dysenteriae (enterotoxin prod)
• e. coli (shinga toxin viz phage)
• salmonella enterica ( non - toxin prod)
• staphylococcus aureus ( enterotoxin )
• giardia lamblia (diarrhea)

treatment = rehydration therapy(electrolytes/water)

Question 12

rotavirus/norovirus

Answer 12

• stomach flu
• dsRNA virus
• highly infectious
• lethal dehydration

Question 13

shigella dysenteriae

Answer 13

• gram neg, bacillus
• endotoxin producer
• invade cell of epithelial mucosa

Question 14

E. coli

Answer 14

• gram neg, bacillus

enteroinvasive type
- invade cell of epithelia mucose
- shinga toxin via phage
- travelers diarrhea

enterohemorrhagic type
- has flagella serotype
- shinga toxin(block host protien syn, dmg endothelia,
cause capillary dmg, loss of blood and clots)
- gastroenteritis

Question 15

salmonella enterica

Answer 15

• gram neg, bacillus

typhoid fever

• salmonellosis
• non toxin producer

Question 16

staphylococcus aureus

Answer 16

• gram pos, staphylococcus
• skin boils
• secrete enterotoxin into prepared foods

Question 17

giardia lamblia

Answer 17

• protozoal infection
• enter through cyst fr contaminated drink water and in
  rodents and pets
• cyst dissolved by acid pH; trophozoite attach intestine
  cell walls
• cause diarrhea

Question 18

treponema pallidum

Answer 18

• spirochete
• std pathogen susceptible to drying and require direct
  physical contact w mucous membranes

syphilis
- 2-6 wk incubation
primary syphilis - at site of infection, painless, full
of spirochetes, untreated = primary latent stage
secondary syphilis - generalized rash
tertiary syphilis - after years; effects heart and cns
congenital syphilis - pregnant mother = fetus;
congenital defects

Question 19

staphylococcus epidermisis

Answer 19

• gram pos; staphylococcus
• has slime layer
• nosocomial(hospital) infection
• penetrate via catheter

Question 20

rabies

Answer 20

• rabies virus(ssRNA)
• trans by animal bite

furious rabies - animal restless, then high excitable
paralytic rabies - animal unaware of surrounding

• multiply in skeletal muscle, then brain = encephalitis
• sym = muscle spasm of mouth, pharynx and
  hydrophobia
• in peripheral nerves virus cant be attacked by
  immune sys till cns destroyed

negri bodies - viral inclusion in affected nerve cells
pre-exposure vaccine - inject human diploid cell
vaccine (hdcv)
post-exposure - vaccine + rabies immune globulin(rig)

Question 21

herpesvirus varicella zoster

Answer 21

chicken pox
- acquire via respiratory and localized skin cells
(form vesicular rash then pustules)
- virus remain latent in pns and cns
shingles
- reactivation of virus: new virions move down pns
to sensory nerves
- vesicular rash, sever burning/stinging, possible
nerve dmg
- acyclovir lessen symptoms
- prevent = live attenuated vaccine