Term
Typhoid Fever
-salmonella typhii
-etiology |
|
Definition
GN rod; not coliform
only salmonella that is ENCAPSULATED, capsule designated antigen that is antiphagocytic; enables agent to survive in macrophages
-facultative intracellular pathogen |
|
|
Term
Typhoid Fever
-salmonella typhii
-epidemiology |
|
Definition
reportable disease
rare in US but common worldwide because of sanitation
carrier is most important; excreted in feces, sometimes urine
transmission:
fecal oral route
high infective dose
vehicle is food, water contaminated with feces or urine from carrier or patient |
|
|
Term
Typhoid Fever
-salmonella typhii
-pathogenesis |
|
Definition
inc period is 8-14 day long
agent multiplies in small intestine - peyers patches in ileum
agent disseminates via lymphatics and blood
agent multiplies intracellulary in macrophages
CMI required to control! esp activated macrophages |
|
|
Term
Typhoid Fever
-salmonella typhii
-clinical manifestations; first week of disease |
|
Definition
onset insiduous
fever is high
headache
anorexia
lethargy
aches/pains
cough
CONSTIPATION not diarrhea |
|
|
Term
Typhoid Fever
-salmonella typhii
-manifestations second week |
|
Definition
elevated temp
mental dullness
apathy
splenomegaly
rose spots maybe |
|
|
Term
Typhoid Fever
-salmonella typhii
-manifesetations 3rd week |
|
Definition
no more fever; symptoms subside
relapses can occur
--ab treatable |
|
|
Term
Typhoid Fever
-salmonella typhii
-manifestations |
|
Definition
| chronic carriers develop in about 3% of cases; organisms nest in gall bladder |
|
|
Term
Typhoid Fever
-salmonella typhii
-treatment |
|
Definition
|
|
Term
Typhoid Fever
-salmonella typhii
-prevention |
|
Definition
control by:
enforcing sanitation
education
uncontaminated water
good sewage disposal
prompt diagnosis and treatment of patients and carriers |
|
|
Term
Typhoid Fever
-salmonella typhii
-vaccines |
|
Definition
for all endemic area travelers
1. vivotif: - oral; 3-4 enteric coated capsules given every other day
-give booster every 5 years
2. typhim Vi - parenteral; purified; single dose |
|
|
Term
Bacillus Anthracis
Anthrax
-etiology |
|
Definition
GP
boxcar shape
encapsulated
spore forming rod
facultative intracellular pathogen with POLYGLUTAMIC acid |
|
|
Term
Bacillus Anthracis
Anthrax
-epidemiology |
|
Definition
|
|
Term
Bacillus Anthracis
Anthrax
-pathogenesis and manifestations |
|
Definition
multiply intracellularly in macrophages
all disease forms result in toxemia and bacteremia; then death
cutaneous anthrax
pulmonary anthrax (wool-sorters disease)
GI anthrax |
|
|
Term
Bacillus Anthracis
Anthrax
-control |
|
Definition
subunit purified for humans
live attenuated for livestock |
|
|
Term
Brucella
-infections it causes |
|
Definition
brucellosis
undulant fever
malta fever |
|
|
Term
|
Definition
GN rods
facultative intracellular pathogens
disease of animals; agent is shed in milk and placenta where it survives for months
species are associated with human infection:
b.abortus = cattle; pasteurization of milk kills agent
b.suis = swine
b.melitensis = goats and sheep
-causes most severe infections; associated with imported unpasteruized cheeses |
|
|
Term
|
Definition
-ingestion of undercooked, raw contaminated meat or unpasteurized milk
-direct contact of infected tissue, blood, etc with abrasions in skin -occupational hazard for vets, slaughter house workers, farmers
-inhalation of infected aerosols via RT |
|
|
Term
|
Definition
inc period is long 2-3 wk
organisms spread via lymphatics while multiplying primarily in macrophages
immunity is CMI mediated |
|
|
Term
|
Definition
acute phase is incapacitating; lasts several weeks or months
onset is insiduous:
malaise
undulant fever (aka periodic nocturnal fever; unknown origin)
weakness
joint pain
headache
night sweats
GI signs
enlarged lymph glands, liver, spleen |
|
|
Term
|
Definition
prolonged; 6 wk min
tetracycline with streptomycin |
|
|
Term
|
Definition
Insects
note: ticks, flies, mosquitos, lice, etc are not the same! they are all unique arthropods |
|
|
Term
|
Definition
dengue is most common vector borne viral disease in the world
lyme disease caused by borrelia burgdorferi is most common tick born disease in US |
|
|
Term
|
Definition
The Plague
the Black Death
it didnt disappear; still endemic in animals |
|
|
Term
|
Definition
bacteria not virus; Ab works!!
small GN pleomorphic coccobacilli which are obligate intracellular parasites
infect endothelial cells (cells lining blood vessels) |
|
|
Term
|
Definition
mammans - humans are accidental hosts except for epidemic typhus
infected ticks via transovarial transmission |
|
|
Term
|
Definition
1. arthropods - ticks, lice
passed by arthropods but not arboviruses
2. ecology of vector is determining factor in disease prevealence |
|
|
Term
|
Definition
mostly through ticks
low infectious dose
parenteral; through bite of infected arthropod
direct human-to-human transmission does not occur |
|
|
Term
|
Definition
after entry, organisms multiple locally; spread to bloodstream; infect endothelial cells of small blood vessels
--can cause death because of this
endothelial cells enlarge; degenerate, resulting in vasculitis in any organ/tissue
microinfarcts (clots) can occur- DIC, damaging vasculature, resulting in fluid loss to tissues, producing edema, hypotensive shock
type and species specific lasting immunity occurs after recovery |
|
|
Term
Rickettsia
-manifestations |
|
Definition
TRIAD OF FEVER, HEADACHE, RASH
-rickettsemia occurs during febrile period
-hypotensive shock and failure in any organ due to DIC which produces ischemia due to poor tissue perfusions |
|
|
Term
|
Definition
tetracycline or chloramphenicol
-doxycycline for ehrlichia
-inhibit protein synthesis; no penicillin or cephalosporin |
|
|
Term
R. Rickettsii
-Rocky Mountain Spotted Fever
-epidemiology |
|
Definition
vector is tick, which is also principle reservoir
-dog tick dermacentor variabilis
-wood tick d. andersoni
mammalian reservoirs - wild animals and dogs
distribution: southeastern states
seasonality - spring and summer |
|
|
Term
R. Rickettsii
-Rocky Mountain Spotted Fever
-manifestations |
|
Definition
inc period is short - one week
prodrome:
first 3-5 days
high fever
chills
headache
myalgia
conjunctivitis - photophobia
sepsis and septic shock bc of vasculitis - meningitis like symptoms
blanching, macular rash bc of vasodilation; 3-5 d after fever on wrist and ankles; spreads to trunk and hands/feet
-if not treated, then rash becomes petechial, then purpuric lesions |
|
|
Term
R. Rickettsii
-Rocky Mountain Spotted Fever
-treatment |
|
Definition
early treatment with tetracycline or chloramphenicol is imperative before lab results are known
-mortality in untreated RMSF is high
-clinical response to treatment is rapid 1-2 days |
|
|
Term
R. prowazekii
-louse-borne, epidemic typhus
-epidemiology |
|
Definition
vector is body louse - pediculus humanus
humans and body lice are natural hosts-humans are reservoir
occurs in crowded conditions - famine, war, concentration camps; natural disaster |
|
|
Term
R. prowazekii
-louse-borne, epidemic typhus
-manifestations |
|
Definition
inc period is short, abt 2 wk
primary infection - abrupt onset of fever, headache, rash (4-7d after onset of S&S; spreads centrifugally sparing face, palms, and soles) rash can evolve to petechial
mortality without therapy is high
--DIC!
brill-zinsser diagnosis - recrudescent typhus; reactivation; milder |
|
|
Term
Bartonella
-rochalimaea
-overview |
|
Definition
not like rickettsia
causes:
trench fever
cat scratch disease
bacillary angiomatosis and peliosis
bartonellosis |
|
|
Term
|
Definition
| fastidious GN rods which are facultative intracellular pathogens that target endothelial cells and RBCs |
|
|
Term
|
Definition
one of most common causes of lymphdenopathy other than neoplasm, tb, and HIV that require urgent medical attention
patients with heart abnormalities or who are immunocompromised should be counseled to avoid cats |
|
|
Term
R. prowazekii
-louse-borne, epidemic typhus
-immunity |
|
Definition
|
|
Term
R. prowazekii
-louse-borne, epidemic typhus
-patient management |
|
Definition
doxycylcine!
cat scratch disease: in immunocompetent patients is mainly supportive bc disease is self limited and resolves in 2-4 months; enlarged lymph nodes may need to be aspirated; cat scratch disease typically does not respond to ab therapy; thus, ab treatment usually not recommended for uncomplicated localized disease
bacillary angiomatosis and peliosis:
use doxycylcine with rifampin
-clarithromycin and azithromycin also show response
relapses in bone and skin happen if ab given for shorter period of time
immunocompromised patients may develop jarish-herxheimer reaction within hours of ab therapy; monitor carefully |
|
|
Term
Trench Fever
-b. quintana
-etiology |
|
Definition
shinbone fever
incapacitating febrile syndrome
bartonella |
|
|
Term
Trench Fever
-b. quintana
-epidemiology |
|
Definition
reservoir: humans and cats
spread by human louse or cat flea
no person to person spread
associated with: poor sanitation, poor hygien, malnutrition
more common in homeless
disease occurs in immunocompetent and compromised individuals |
|
|
Term
Trench Fever
-b. quintana
-manifestations |
|
Definition
insiduous - sudden onset of symptoms 5-7 days; then they abate
but symptoms recur every 4-5 days
recurrences can continue for a year
symptoms:
fever
malaise
headache
night sweats
splenomegaly
bone pain - shinbone fever; becomes more severe each time
transient rash may appear |
|
|
Term
Cat Scratch Disease
-b. henselae
-epidemiology |
|
Definition
affets compromised and immunocompetent pts
transmitted via cat bite/scratch or bite by infected cat flea
manifestations: regional lymphadenitis + FEVER after contact with cat |
|
|
Term
Borrelia burgdorferi
-lyme disease
-etiology |
|
Definition
most common tick borne disease in US
extracellular spirochete not observed after gram staining; need dark field microscopy - not seen on blood smear
agent of lyme disease in north america and europe
other species of borrelia are responsible in eurasia |
|
|
Term
Borrelia burgdorferi
-lyme disease
-epidemiology |
|
Definition
incidence:
connecticut
rhode island
new york
new jersey
pennsylvania
wisconsin |
|
|
Term
Borrelia burgdorferi
-lyme disease
-reservoirs |
|
Definition
| small mammals (white footed mouse) and birds |
|
|
Term
Borrelia burgdorferi
-lyme disease
-vector |
|
Definition
hard body ticks
4 stages in development:
egg, larva, nymph, adults
each stage feeds only once for several days
nymphs feed on and transmit infection to small mammals or humans
-NYMPHS ARE RESPONSIBLE FOR MOST HUMAN INFECTIONS
only find adults in winter
-adults feed on and transmit agent to larger mammals
-not passed from mom to eggs; eggs release larvae that is unaffected; larvae becomes nymph; nymph becomes infected; gets into adult |
|
|
Term
Borrelia burgdorferi
-lyme disease
-immunity |
|
Definition
|
|
Term
Borrelia burgdorferi
-lyme disease
-pathogenesis |
|
Definition
|
|
