Other Zoonotic Bact. I/II

Question 1

Shape of Leptospira?

Answer 1

small, thin, spiral shaped (question mark shaped)

Question 2

Where do we find Leptospira and where does it go in the body?

Answer 2

endemic in tropical regions (Hawaii); associated with water sports/ swimming
travels through blood and infects various organs esp. kidney (high CK/ azotemia) and liver

Question 3

Discuss the lab findings of Leptospira

Answer 3

Lab: Can be grown aerobically in appropriate media

Question 4

Symptoms of Leptospira

Answer 4

Sx: Acute febrile illness with conjunctival suffusion (reddening with no pus) that may progress to jaundice and renal failure (Weil’s disease), pulmonary hemorrhage or meningitis.

Question 5

Who are at risk for Leptospira

Answer 5

At risk: animal urine–> contaminated water→ Soldiers wading in water/streams during field exercises

Question 6

Source of Lyme Disease? Discuss the life cycle of this thing,

Answer 6

Source: hard ticks (ixodes scapularis family) type: Deer ticks

Life cycle: White footed mouse= reservoir for larvae; white tailed deer = obligatory host for adult form (deer immune)

Question 7

Who is at risk for Lyme Disease?

Answer 7

Risk: NE and midwest USA– Most common arthropod-borne infection in the U.S.

Nymph stage of the tick in the months of May - July is the most contagious.

Question 8

How do we diagnose Lyme Disease

Answer 8

Dx: blood culture and PCR (Synovial fluid if they have arthritis), ELISA/western blot, Wright stain, Giemsa stain

Question 9

Discuss the symptoms of Lyme Disease

Answer 9

Stage 1: 2-7 days: (localized infection) bull’s eye rash (w/in a month of bite), flu sx (fever+chills)
(Local spread) erythema migrans

Stage 2: weeks to months later:(disseminated infection) bilateral bell’s palsy, heart block caused by myocarditis, erythema migrans in other locations

Stage 3: months to years: (persistent infection) lyme encephalopathy (memory problems, meningitis or other CNS sx), migratory polyarthritis starting w/ large joints (like knee), acrodermatitis
FACE: facial nerve palsy, arthritis, cardiac block, erythema migrans

Question 10

Lyme’s Disease is similar to STARI. What is STARI all about?

Answer 10

**similar to: STARI - Southern Tick-Associated Rash Illness - lyme-disease like rash seen in people residing in southeastern and south-central US; cause =the lone-star tick (Amblyomma americanum), but bacterial agent is unknown

Question 11

Treatment of Lyme Disease

Answer 11

Tx: Doxycycline (stage 1), Ceftriaxone (stage 3)

Question 12

Discuss the symptoms of Relapsing fevers

Answer 12

Sx: Relapsing fever - recurrent episodes of fever x3-5 days (+HA, myalgia, vomiting) separated by asymptomatic intervals.

incubation period ~6 days

initially: sudden chills, high fever, tachycardia, delirium, red macular rash on trunk and extremities (erythema multiforme)
relapse: fever, arthralgia, jaundice

can lead to: hepatosplenomegaly, myocarditis, heart failure

Question 13

Louse born vs. Tick born relapsing fever

Answer 13

Louse(lice)-borne (Borrelia recurrentis)= transmitted from person to person with no animal reservoir (louse/lice is crushed on host and leaks Borrelia) = epidemic form

Tick-borne (Borrelia hermsii)= transmitted from animals to humans by soft ticks (Ornithodoros hermsi)= endemic form.

Question 14

Who is at risk for Louse born vs. Tick born?

Answer 14

Louse: Risk:mountains in Africa/S. Ameria. war areas and refugee camps

Tick: Risk: western US in summer. Sleeping in rodent-infested cabins in the mountains

Question 15

Treatment of Relapsing fever

Answer 15

Tx: doxy/ tetracycline or erythromycin

Question 16

Discuss the lab and structure for Rickettsia

Answer 16

G(-) coccobacillus bacteria (ovoid shaped)

gram stains poorly (but can use Giemsa stain)

obligate intracellular (get NAD+ and CoA from eukaryotic cells for bacterial replication),

nonmotile (spread from cell to cell w/ actin polymerization), nonspore-forming

Question 17

Discuss the symptoms of Ricketssia rickettsii

Answer 17

Rocky Mountain Spotted Fever

sx: spotted fever, n/v, red eyes, rash (small, flat pink macules on extremities)

later sx: rash becomes darker small spots and moves centrally

can lead to: renal failure, myalgia, skin necrosis, pneumonia, brain infarct, death

Question 18

Pathogenesis of Ricketssia Rickettsii

Answer 18

patho: invades endothelial cells and induces cells to phagocytose more bacteria

Question 19

Labs for RMSF (Rocky Mountain Spotted Fever)

Answer 19

labs: IgG or IgM antibodies on IF, PCR detects rickettiae DNA

Question 20

Treatment for Rocky Mountain Spotted Fever

Answer 20

tx: doxycycline (side effect in children: teeth staining)

Question 21

Talk about Rickettsialpox

Answer 21

Source: rodents → mites → humans
Sx:Rickettsialpox Rash like chicken pox (papulovesicular). Eschar at bite site
Seen in US

Question 22

Discuss Rickettsia prowazeki

Answer 22

Source: body louse vector to squirrel reservoir
Sx: epidemic typhus
Not seen in US (seen in Somalia)

Question 23

Discuss Rickettsia Typhi

Answer 23

Source: flea-borne vectors, rodent reservoir
Sx: endemic or murine typhus
Seen in the US and worldwide

Question 24

Talk about Orienta Rickettsia

Answer 24

Source: mites, chiggers
Sx: scrub typhus
Not in US, in Vietnam

Question 25

Talk about Anaplasmataceae:

Answer 25

G(-) small bacteria , intracellular (in cytoplasmic vacuoles of hematopoietic cells) histo: morulae- basophilic and intracytoplasmic inclusions

Question 26

What type of bacteria are Anaplasma phagocytophilum and where do they hide

Answer 26

G(-) small bacteria , intracellular (in granulocytes/neutrophils)

Question 27

Discuss the source and transmission for Anaplasma phagocytophilum

Answer 27

Source: hard ticks (ixodes scapularis family) type: Deer ticks cattle/sheep → ticks → humans

Question 28

Discuss the symptoms for Anaplasma phagocytophilum

Answer 28

sx: similar to RMSF, but more abrupt fever, chills, HA, malaise,hemorrhagic gastroenteritis

Question 29

Discuss the risk for Anaplasma Phagocytophilum and what it is associated with

Answer 29

risk: NE and mid-atlantic US a/w: coinfection with lyme disease and babesiosis

Question 30

Discuss the structure of Coxiella and the transmission of it

Answer 30

G(-) obligate intracellular (in phagolysosomes) source: cattle/sheep → ticks → humans spores spread through animal droppings: Spread to humans via aerosol transmission; often in farmers, veterinarians

Question 31

Discuss the symptoms of Coxiella

Answer 31

sx: malaise, flu-sx, abrupt fever, profuse sweating, AMS, n/v/d, headache can lead to: atypical pneumonia, ARDS, hepatitis, endocarditis

Question 32

Discuss the symptoms of Coxiella

Answer 32

tx: cephalosporin (1st gen); often self limiting

Question 33

Discuss the source and structure of Yersinia Pestis

Answer 33

Gm (-) rod, safety pin appearance Source: flea vector, occurs naturally in southwestern US grasslands Cycles through rodents (mainly prairie dogs) → domestic animals and humans (cats can transmit by resp. droplets)

Question 34

Discuss the pathology of Yersinia Pestis and when we see outbreaks occur

Answer 34

Outbreak common in cool summers following wet winters. Path: flea bites and regurgitates bacteria→ vesicular lesion→ phagocytosis by PMNs→ killed in PMNs or released→ can now resist further phagocytosis→ travel to lymphatics and localized to a lymph node (bubo) → stops here or disseminates

Question 35

Discuss the symptoms of Yersinia Pestis

Answer 35

Sx: “black death” (acral gangrene), lymph node bubo, skin ulcers and eschar at bite site, pneumonia, septic shock, meningitis; systemic leading to organ abscess, DIC, necrosis

Question 36

Virulence factors for Yersinia Pestis

Answer 36

Exotoxins Yops (yersinia-associated outer proteins) secreted by Type 3 secretion system: inhibit cytokine produce and phagocytosis

Question 37

How do we diagnose and treat Yersinia Pestis

Answer 37

Dx: grows on McConkey agar, Wayson staining shows light blue bacilli with dark blue polar bodies Tx: aminoglycosides (streptomycin) + tetracycline Vaccine: killed vaccine

Question 38

Discuss the structure of Tularemia

Answer 38

Gm (-) coccibacilli, facultative intracellular (grows in macrophages) -> depends on cell mediated immunity

Question 39

Tularemia Source

Answer 39

Source: hard ticks (Ixodidae dermacentor), rabbits are main reservoir. transmission: direct contact or aerosolized (terrorism threat)

Question 40

Discuss symptoms of Tularemia

Answer 40

Sx: spectrum. general malaise, fever, HA ulcers+glands: painful lesion at site of infection→ regional lymphadenopathy (granulomas with caseating necrosis of reticuloendothelial organs like lymph nodes) eyes: conjunctiva infected lungs: pneumonia GI: typhoid fever sx

Question 41

Discuss how we diagnose and treat Yersinia Pestis

Answer 41

Tx: aminoglycosides (streptomycin) Dx: serum titers, culture (requires cysteine- chocolate agar or BCYE), faint gram stain, agglutination test

Question 42

Discuss the structure of Brucella

Answer 42

G(-) small coccobacilli, facultative intracellular, non-encapsulated, flagellated, ability to survive in macrophages

Question 43

Source of Brucella

Answer 43

source: no arthropod vector-- contaminated foods (unpasteurized milk/cheese), direct infected animal contact (hogs, elk, moose), animal tissue high in erythritol

Question 44

Who is at risk for Brucella

Answer 44

at risk: vets, hunters, meat-processing targets RES organs (may or may not cause enlargement of these organs); causes cell lysis and spreads systemically; osteomyelitis

Question 45

Symptoms of Brucella

Answer 45

sx: granulomas, bacteremia, undulating fever/chills/night sweats/weight loss. can lead to: hepatic lesions, arthritis, meningitis, endocarditis

Question 46

Discuss the pathology of Brucella

Answer 46

Path: enter via mucous membranes/skin,GIT,inhalation→ eaten by PMN/macrophage→ lymph nodes→ replicate in macrophages→ phagocytic cells travel to reticuloendothelial system organs (spleen/liver/lymph nodes)--> either stops or forms granulomas with recurrent bacteremia

Question 47

Discuss how we diagnose and treat Brucella

Answer 47

dx: serology tx: doxycycline and rifampin

Question 48

Discuss the source of Bartonella Henselae

Answer 48

immunocompetent pts→ cat-scratch fever immunocompromised pts → bacillary angiomatosis (endothelial proliferation of raised red vascular lesions) source: cats, ticks, fleas

Question 49

Discuss the symptoms and diagnosis for Bartonella Henselae

Answer 49

sx: red, tender, swollen lymph node diag: Warthin Starry stain (silver stain)

Question 50

Discuss treatment for Bartonella Henselae

Answer 50

Tx: catch scratch is usually self limiting but can use azithromycin; bacillary angiomatosis: macrolides, doxycycline

Question 51

What is Bartonella Quintana

Answer 51

trench fever source: lice (body louse) sx: 5 day fever, bacteremia

Question 52

What is Bartonella Baciliformis

Answer 52

carrion’s disease source: sand fly sx: 1. oroya fever (hemolytic anemia) 2. verruga peruana