Other Zoonotic or Vector Borne diseases Flashcards
francisella tularensis
causes rabbit fever/tularemia/glandular fever
Gram neg rod that grows in macrophages, cysteine-supplemented media required
vector is hard tick or contact with infected rabbit
VERY infectious –> low infectious dose
at risk: hunters, vets, lab workers
francisella tularensis
small gram - coccobaccilus/rod
grows in macrophages
causes tularemia/rabbit fever/glandular fever
different tularemia infections
Ulceroglandular tularemia - d/t primary infection of the skin
-skin ulcer (animal/insect bite), Swollen and painful LNs, fevers, chills
Oculoglandular tularemia - affects the eyes/conjunctiva
- Eye pain, redness, swelling, eyelid ulcer, light sensitivity
Pneumonic tularemia - resembles pneumonia; aerosol transmission or spread to lungs
-Dry cough, Chest pain, Difficulty breathing
Typhoidal tularemia - d/t ingestion
-High fever, exhaustion, N/V/D, hepatosplenomegaly, Pneumonia
culture medium for tularemia requires
cysteine
brucella species
intracellular parasites of the RES in humans
no vector!!, genitourinary pathogen in animals –> shed in milk
-acquired by infected milk or contact with cattle, sheep, pigs, goats
causes brucellosis (undulant fever)
increased risk factors for brucellosis
- slaughterhouse workers and meat-packing
- vets/lab workers/hunters
and
UNpasteurized cheeses (tourists!!!)
pathogenesis of brucellosis
multiplies in macrophages and phagocytic cells of the RES
creates granulomas with recurrent bacteremia
chronic brucellosis (undulant fever) symptoms
Incubation period: 2- 8 weeks
Fever, night sweats, headaches, chills, myalagia, weight loss
Organs of the RES often NOT enlarged
Complications = hepatic lesions, arthritis, meningitis, and endocarditis
bartonella diseases and their vectors
bartonella henselae (cat scratch) = flea
bartonella quintana (trench fever) = lice
bartonella bacilliformis (carrions disease) = sand fly
cat scratch disease
bartonella henselae
cat flea is vector
in immuno competent –> catscratch disease (inflammation)
in immuno compromised –> bacillar angiomatosis (erythrocyte and endothelial colonization)
bacillary angiomatosis
due to bartonella
trench fever
caused by bartonella quintana
vector is lice; human reservoir
5 days of fever (febrile bacteremia) in immuno competent
immunocompromised –> bacillary angiomatosis and endocarditis
bartonellosis by nartonella bacilliformis
vector is sandfly; human reservoir
causes Biphasic disease –> carrions disease
1st phase = oroya fever (hemolytic anemia)
2nd phase = verruga peruana (blood filled/purple warts)
treatment for cat scratch disease?
azithromycin
rickettsiaceae bacteria
obligate intracellular bacteria that are usually transmitted by arthropods
gram -coccobacilli; visible with giemsa stain
2 types - rickettsia and orientia.
R. Rickettsii causes….
RMSF rocky mtn spotted fever
vector = ticks
spread of rickettsia from cell to cell involves….
actin polymerization
pathogenesis of spotted fever and typhus (rickettsiaceae)
vasculitis!!
caused by proliferation of the organisms in the endothelial lining of small vessels
vascular lesions in skin are prominent
rickettsia rickettsii
cause of RMSF
tick borne
tick vector in the west
tick vector in the east
tick vector in part of arizona
west = dermacator andersonii
east = dermacator verabilis
az = rhipicephalus sanguineus
rocky mountain spotted fever
d/t R. rickettsii
best treatment for rickettsial infections including RMSF?
doxycycline
rickettsia akara
Cause of rickettsial pox
mite-borne (rodent –> mite –> human)
occurs in USA and everywhere.
Rash more like that of chicken pox (papulovesicular); Eschar at site of mite bite (mimics cutaneous anthrax)
rickettsia prowazekii
cause of epidemic typhus
Body louse
not in USA; in places of war (Somalia)
rickettsia typhi
Cause of endemic or murine typhus
disease occurs worldwide to include USA (Gulf Coast area)
flea-borne; rodent vectors
ehrlichia and anaplasma
obligate intracellular bacteria that survive in cytoplasmic vacuoles of mammalian hematopoetic cells
(in contrast to Rickettsia and Orientia that live in endothelial cells)
Rickettsia and Orientia
vs
ehrlichia and anaplasma
R/O – live in endothelial cells
E/A - live in cytoplasmic vacuoles of mamal hematopoetic cells
lone star tick is geographically located
south east US
anaplasma phagocytophilum
primarily infects granulocytes (neutrophils and rarely eosinophils).
The pathogen is often referred to as the agent of HGE.
Transmitted by Ixodes scapularis -can co-transmit the agent of Lyme disease, Borrellia burgdorferi
coxiella burnetii
humans infected through contact with cattle, goats, sheep
ticks probably important in animal to animal transmission
flu like illness (Q fever) –> atypical pneumonia; rarely endocarditis
Ticks cause….(8)
Mites cause…(2)
Lice cause…(3)
Fleas cause… (4)
Ticks-Lyme disease, HGE, HME, STARI, endemic relapsing fever, RMSF and sometimes tularemia and Q fever
Mites-Scrub typhus, Rickettsialpox
Lice-Trench fever, epidemic typhus, epidemic relapsing fever
Fleas- endemic typhus (=murine typhus), murine typhus like, bubonic plague, cat scratch fever
characteristics of ticks that make them high potential vectors
- Persistent bloodsuckers - attach firmly
- Slow feeding - allows wide dispersion
- Highly sclerotized - resistant to environmental stresses
- Relatively free from natural enemies
- Wide host range - certain source of blood
- Longevity - may live 14 years or more (soft ticks)
- Transovarian transmission - pass infection onto progeny
- Reproductive potential - may deposit up to 18,000 eggs
