Other Zoonotic Bact. I/II Flashcards Preview

Final Multisystems Microbiology > Other Zoonotic Bact. I/II > Flashcards

Flashcards in Other Zoonotic Bact. I/II Deck (52)
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Shape of Leptospira?

small, thin, spiral shaped (question mark shaped)


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

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


Discuss the lab findings of Leptospira

Lab: Can be grown aerobically in appropriate media


Symptoms of Leptospira

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.


Who are at risk for Leptospira

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


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

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)


Who is at risk for Lyme Disease?

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.


How do we diagnose Lyme Disease

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


Discuss the symptoms of Lyme Disease

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


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

**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


Treatment of Lyme Disease

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


Discuss the symptoms of Relapsing fevers

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


Louse born vs. Tick born relapsing fever

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.


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

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


Treatment of Relapsing fever

Tx: doxy/ tetracycline or erythromycin


Discuss the lab and structure for Rickettsia

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


Discuss the symptoms of Ricketssia rickettsii

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


Pathogenesis of Ricketssia Rickettsii

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


Labs for RMSF (Rocky Mountain Spotted Fever)

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


Treatment for Rocky Mountain Spotted Fever

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


Talk about Rickettsialpox

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


Discuss Rickettsia prowazeki

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


Discuss Rickettsia Typhi

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


Talk about Orienta Rickettsia

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


Talk about Anaplasmataceae:

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


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

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


Discuss the source and transmission for Anaplasma phagocytophilum

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

cattle/sheep → ticks → humans


Discuss the symptoms for Anaplasma phagocytophilum

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


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

risk: NE and mid-atlantic US

a/w: coinfection with lyme disease and babesiosis


Discuss the structure of Coxiella and the transmission of it

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