8. Zoonoses

  1. zoonoses
    infectious diseases that can be transmitted from animals to humans
  2. bubonic plague incidence
    • killed off 1/3 of world's population in 14th century
    • rare today
  3. bubonic plague etiologic agent
    yersinia pestis
  4. bubonic plague reservoir and transmission
    • rodents and their fleas
    • when rodent dies, fleas hop to nearest warm body
  5. bubonic plague clinical manifestations
    bubonic plague - lymph nodes hemorrhage and form buboes, not communicable

    pneumonic plague - bacteria enter the blood and lungs, communicable by respiratory route
  6. bubonic plague diagnosis
    direct smear of material from the bubo - reacted with serum
  7. bubonic plague treatment
    streptomycin - very effective if given in time
  8. bubonic plague prevention
    • killed vaccine available - for laboratory personnel and people working in endemic areas
    • prophylactic antibiotics
    • surveillance of wild rodent population
    • rodent extermination in residential areas
    • avoid getting close or touching with rodents
    • use insect repellent to prevent flea bites
    • inspection of ships and harbor areas to prevent transport to new locations
  9. lyme disease outbreak investigation
    • 2 concerned mothers reported cases of arthritis
    • epidemiologists did surveillance - patients remembered tick bite
    • penicillin and tetracycline improved condition - bacteria
  10. signs and symptoms associated with Lyme disease
    • single red lesion that expanded to bullseye
    • fever, chills, headache, stiff neck
    • arthritis
  11. organism causing Lyme disease
    Borrelia burgdorferi
  12. Lyme disease reservoir
    • deer, field mice, woodrat
    • ticks transmit by feeding on animals
  13. emergence of Lyme disease as a new disease
    due to tremendous increase in the deer population because it is no longer hunted as much
  14. Lyme disease diagnosis
    serological test with antibodies
  15. Lyme disease treatment
    doxycycline and amoxicillin early can prevent late stages
  16. Lyme disease prevention
    • preventing tick bites -
    • over skin when walking through underbrush
    • stick to cleared trail when hiking
    • use insect repellent
    • pregnant women should be careful
    • vaccine
  17. toxoplasmosis etiology
    toxoplasma gondii - protozoan
  18. toxoplasmosis reservoir and transmission
    • cat
    • definitive host - reproduces inside
    • humans are intermediate host

    • fecal-oral, cat's feces to human mouth
    • humans become infected while cleaning cat litter, children playing in sandbox or dirt, or eating undercooked meat from infected animal
  19. toxoplasmosis clinical manifestations
    • asymptomatic for most adults unless immunocompromised
    • small children have fever, rash, pneumonia and encephalitis (infection of brain)
    • most serious to fetuses, can cross the placenta and lead to hydrocephaly (fluid in brain), blindness, mental retardation
  20. toxoplasmosis diagnosis
    • direct smear seed with microscope
    • serological test
  21. toxoplasmosis treatment
    sulfonamides and pyrimethamine
  22. toxoplasmosis prevention
    • don't have a cat or have it go to the bathroom outside, be careful for contamination
    • have a completely indoor cat
    • keep cats from defecating where children play
    • cook all meat thoroughly
    • pregnant women should be especially careful
  23. rabies etiology
    rabies virus - RNA
  24. rabies reservoir and transmission
    • dogs and cats in developing countries
    • wild animals in US- require vaccines

    virus shed in saliva, transmitted in bites, bats-feces
  25. rabies clinical manifestations
    • destroys nerve cells
    • fever, nausea, vomiting
    • agitation, spasms of throat muscles, frothing
    • delirium, coma, death
  26. rabies diagnosis
    • kill and make sections of animal's brain and react with labeled antibody, look for clusters of virus
    • quarantine animal to see if signs develop
  27. rabies treatment
    • passive immunization immediately around the wound
    • vaccination to stimulate active immunity
    • incubation period is long - vaccine still has time to work if given after exposure
  28. rabies prevention
    • vaccination of dogs and cats
    • vaccination of people with professional risk or travelers going to high incidence area
    • vaccination and quarantine of imported animals
Card Set
8. Zoonoses
public health microbiology midterm 2 lecture 8