Zoonotic Flashcards
Yersinia Pestis
The plague
Bipolar safety pin staining (giemsa)
Bubo or petichiae
Type III secretion - in epithelial or macrophages
VW surface antigen (tyrosine P, cytotoxic factors, coagulase-fibrinolysin)
Enzootic vs epi
Enzootic - stable rodent-flea cycle w/out excessive host mortality
Epizootic - when introduced into the rodent/animal that are susceptible
Zootic = transmission animals to humans
Types of plague
Bubonic - lymph gland swelling from flea 2-5 days earlier. 60-90% mortality (most common)
Septicemic - invasion all organs, death 12-24 hours
Pneumonic - 1/2* lung infection highly infectious and 100% mortality w/out treatment
Francisella Tulerensis
From rabbits, fleas, cats… no person to person
Gram neg coccobacillus
Requires cysteine to grow, intracellular, phase variation
Type A most common (A1b most fatal)
Tx: Streptomycin/gentamicin, levofloxine or doxycycline
Types of Tularemia
Glandular: tick bite
Ulceroglandular: breach of skin w/ direct animal ulcers (80%)
Oculoglandular: inoculation in eye
Typhoidal: ingestion contaminated material
Pulmonary: inhalation (most deadly)
Lyme (borrelia burgdorferi)
Arthritis type presentation, chronic fatigue, erythema migrans (1-4 wks)
Ticks (blacklegged, lone star, dog) that have fed off white-tail deer. 10-36% carry it. Most often in nymph stage
Northeast & midwest
Spirochete - antibody to surface protein D for detect or darkfield
Tx: doxycycline, ceftriaxone 2-4 weeks in
Lyme stages
Incubations 3-30 days
Stage 1: localized, erythrema migrans, 1-4 wks
2: disseminated, 6 months, annular skin lesions, meningitis, carditis, MSK pain, eye
3: persistent up to 30 years, acrodematitis chronica, arthritis, encephalopathy, polyneuropathy, cardiomyopathy
Rickettsia
Carried by body lice
Obligate intracellular gram neg rods/coccobaccilli
Giemsa stain have to be cultivated in cells or egg yolks
Don’t have LPS/peptidoglycan (get cholesterol from host cells)
Affect epithelial
Use IFA to Dx
Sx: high fever, headache, petechial rash, can spread to organs
Tx: doxycycline
Rickettisia diseases
Rocky Mtn Spotted fever (ticks) rickettsii. Centripetal rash. Most common. Typhus: epidemic (lice), prowazekii; Brill's; murine fleas = typhi. Cetrifugal rash Scrub Typhus (chiggers): orientia tsutsugamushi. No rash
Ehrlichia & Anaplasma
Obligate intracellular, infect phagocyctic cells & mult in vacuoles Ticks Sx: fever, HA, malaise, no rash Leukopenia, thrombocytopenia ALT/AST elevations Tx: tetracycline (HME) Doxycycline (Ana)
Rabies
Rhabdoviridae of Lyssavirus
Bullet-shaped, non-segmented neg RNA, lipid envelope
To humans by animal bite -> replicates at wound -> infect nerves -> CNS & replication (now too late)
Unique variant per species
Asia and Africa
Without treatment = fatal
Tx = human rabes immunoglobulin & 4 dose vaccine)
Rabies Stages
Incubations: 1-3 months
Encephalitic (80%): hydrophobia, difficulty swallowing, hallucination, hypersalivation, brain stem dysfxn
Paralytic (20%): quadriparesis, multiple organ failure
Hantavirus
Of Bunyaviridae Genus 3 segments, neg ssRNA Aerosols of rodent urine Hemorrhagic fever with renal syndrome Hantavirus pulmonary syndrome
Hantavirus pulmonary syndrome
Sin Nombre is N. American (4 corners) variant in deer mouse
SOB, fever, myalgia (severe legs & back), headache, cough, rapid respiratory failure
Low platelet, neutrophilia, high LDL & ALTs
40% mortality no Tx
Lassa Virus
W. africa, rodens, hemorrhagic fever
