Zoonoses -Bac Inf 2 Flashcards
rocky mountain spotted fever- group, organism, distribution, vector, and reservoir
- spotted fever group
- rickettsia rickettsii
- North and South America
- tick
- rodents, dogs
rickettsialpox- group, organism, distribution, vector, and reservoir
- spotted fever group
- rickettsia akari
- US, russia, korea, Africa
- mite
- mouse
epidemic typhus- group, organism, distribution, vector, and reservoir
- typhus group
- rickettsia prowazekki
- Africa, Asia, South America
- body louse
- humans, squirrel, fleas, flying squirrels
endemic (murine) typhus- group, organism, distribution, vector, and reservoir
- typhus group
- richettsia typhi
- worldwide
- fleas
- rodents
scrub typhus- group, organism, distribution, vector, and reservoir
- scrub typhus group
- orientia tsutsugamushi
- asian and the pacific
- mite vector
- rodent reservoir
human granulocytic ehrlichios (HGE)- group, organism, distribution, vector, and reservoir
- ricketsia like organism
- anaplasma phagocytophilium
- Europe, Asia, North and SOuth America
- Tick vector
- rodents, horses, dogs, cattle
human monocytic ehrichiosis (HME)- group, organism, distribution, vector, and reservoir
- ricketsia like organism
- ehrlichia chaffeensis
- US
- ticks vector
- deer, dogs, foxes, racoons
Q fever- group, organism, distribution, vector, and reservoir
- ricketsia like organism
- Coxiella burnetti
- Worldwide
- no vector to humans
- sheep, cattle, goats
trench fever- group, organism, distribution, vector, and reservoir
- ricketsia like organism
- bartonella quintana
- Europe, Africa, Asia
- body louse vector
- human reservoir
cat scratch fever- group, organism, distribution, vector, and reservoir
- ricketsia like organism
- bartonella henselae
- Worldwide
- No vector
- cat and dog reservoir
Rickettsia - organism details
- very small gram negative coccobacilli
- difficult to stain and see
- has LPS
- obligate intracellular pathogen –> grows in the cytoplasms –> trick cells to phagocytose them
- transmitted by arthropods (ticks mites and lice)
Rickettsia - pathology
- most people definitely have symptoms
- organism infects vascular endothelium of small blood vessels
- skin or systemic disease
rickettsia - skin symptoms
- SMALL BLOOD VESSELS USUALLY
- inflammation, endothelial cell proliferation, thrombosis and red cell leakage results in the formation of a rash or petechial lesion
rickettsia - systemic disease symptoms
vascular lesions throughout the body and are dependent on the virulence and tissue trophism of the individual species involved
rocky mountain spotted fever (RMSF)- causative organism? transmission via, host, patient presentation
- rickettsia rickettsii
- vector = Ticks
- host = small rodent
- -rash on feet, ankles, hands and wrists
- fever
rickettsialpox - patient presentation, vector?
- rash on trunk
- vector = mites
rocky mountain spotted fever -most commonly seen where? peak season?
- Delaware down to southcoast of Florida(South Atlantic group)
- April and September = peak tick season
rocky mountain spotted fever - disease progression
- Initially presentation of fever AND THEN rash
- rash on feet, ankles, hands, and wrists
- Untreated: disseminated intravascular coagulation (DIC), thrombocytopenia, pulmonary edema, renal failure, gastrointestinal hemorrhage and shock
rocky mountain spotted fever - diagnosis
- Epidemiology and Clinical Signs
- Serology: severe disease (death) may develop before antibody titers are high enough to be detected
- Molecular or immunohistochemical techniques: detect the presence of organism in blood or tissue biopsy
- difficult to diagnose - hard to grow and disease moves fast
rocky mountain spotted fever - treatment/prevention
-Treatment:
Initiated therapy based on clinical symptomology and epidemiology
Doxycycline is the drug of choice
-Prevention: Limit exposure to ticks
Rickettsial Pox - organism, vector, reservoir
- Caused by Rickettsia akari
- Transmitted by mites which feed on infected rodents
- reservoir: house mouse (Mus musculus)
Rickettsial Pox- diagnosis/treatment
- Immunohistochemistry and serology support diagnosis
- Doxycycline or tetracycline for treatment
- mild and can usually resolve on its own
Rickettsial Pox-disease progression
-Initial signs: a painless papule at the site of inoculation which over time becomes ulcerated and scabs over (eschar) –> RASH ON TRUNK!
-Second phase: fever, chills, headache, myalgias, and photophobia
pox-like eruptions which scab over and become crusted
-Usually mild and uncomplicated
lesion with black center is usually?
Rickettsial Pox
Epidemic Typhus - causative organism? where most often?
- Rickettsia prowazekii
- not seen in deveolped naitons –> more like war, poverty, prisons, refugee camps
- if in the US usually in Southeast (flying squirrels –NOT REPORTABLE
Epidemic Typhus - vector? how does organism present and how does it enter body?
- Spread by body lice (Pediculus humanus corpis)
- organism present in lice feces
- inoculated through scratching
Epidemic Typhus - disease presentation
- Very high fever (~104 F), conjunctivitis, severe headache, myalgias, arthralgias, dry cough, nausea, vomiting and diarrhea
- Followed by development of rash
- progresses from pink and spotted to deep red and raised
- begins near the armpits and spreads over torso to limbs
- The face, hands, and feet are generally spared
- Complications include myocarditis and CNS dysfunction.
- Fatality rates of 10-40% have been reported in untreated
Epidemic Typhus - diagnosis/treatment/prevention?
-Diagnosis: Serology or molecular techniques
-Treatment: doxycycline or chloramphenicol
-Prevention:
control lice infestation
live attenuated and formaldehyde fixed vaccines available
use limited to high risk populations.
RASHES - typhus vs rocky mountain spotted fever
RMSF = starts at hands and feet and moves toward torso typhus = starts at armpits--> spreads to torso (NOT ON FACE, HANDS AND FEET
Endemic of Murine Typhus - organism, transmission/vector, where found most often?
- Caused by R. typhi
- Transmitted by the rat flea (RODENT TO HUMAN VIA RAT FLEA)
- Texas gulf coast
Endemic of Murine Typhus - symptoms/presentation?
- more benign with fewer complications that epidemic typhus
- Very high fever (~104 F), conjunctivitis, severe headache, myalgias, arthralgias, dry cough, nausea, vomiting and diarrhea
- Followed by development of rash
- progresses from pink and spotted to deep red and raised
- begins near the armpits and spreads over torso to limbs
Endemic of Murine Typhus - treatment/diagnosis
- Diagnosis: Serology or molecular techniques
- Treatment: doxycycline or chloramphenicol
Scrub Typhus/Tsutsugamushi fever - orgnaism, where is it a problem? transmission/vector, reservoirs? (DONT WORRY ABOUT SCRUB SO MUCH)
- Endemic in southern and eastern Asia, the Pacific Islands, and northern Australia
- Caused by Orientia tsutsugamushi
- Transmitted through the bite of infected mites
- A wide range of rodents, lagomorphs and marsupials serve as reservoirs
Scrub Typhus/Tsutsugamushi fever - disease presentation? (DONT WORRY ABOUT SCRUB SO MUCH)
- Inoculation develops from papule to ulcer to eschar
- Followed by fever, severe headache, myalgia, swollen lymph nodes, and photophobia
- ~1 week later a slightly raised rash appears on the truck and spreads to the extremities
- Last several days
- Symptoms resolve within 2 weeks, even in the absence of treatment
- Complications include pneumonia and myocarditis
- Mortality rates can approach 30%
Scrub Typhus/Tsutsugamushi fever - diagnosis/treatment? (DONT WORRY ABOUT SCRUB SO MUCH)
- Diagnosis: symptomology, epidemiology, and serology
- Treatment: doxycycline or chloramphenicol
Ehrlichia and Anaplasma - organism details
- Small Gram-negative intracellular bacteria
- Primarily parasitize monocytes (ehrlichia) and granulocytes (anaplasma) –> BOTH hide from immune –>disrupt fusion of phagosome with lysosome
- Replicate and form vacuole-bound colonies known as morulae
- Organisms remain within vacuoles, do not escape into the cytoplasm
- Little or no peptidoglycan or LPS as part of their cell wall
HUMAN MONOCYTIC EHRLICHIOSIS (HME): organism
Ehrlichia chaffeensis - monocytes
HUMAN GRANULOCYTIC EHRLICHIOSIS (HGE): organsim
Anaplasma phagocytophilium - granulocytes
Ehrlichia and Anaplasma - peak season?
April and September - tick season
HME: Ehrlichia chaffeensis - vector, reservoir, location in US
- lone star tick***
- white tail deer***
- Primarily in the South East, Mid-Atlantic, Midwestern, and South Central regions of the United States
HGE: Anaplasma phagocytophilium - vector, reservoir, location in US
- Ixodes ticks
- small mammals
- Found primarily in the North Central Midwest, the North East and Central Atlantic regions of the US
HME: Ehrlichia chaffeensis - presentation/sypmtoms
- petechial rash –> generalized rash
- 60% asymptomatic and the rest super sever
- severe=cough, dyspnea, respiratory distress, CNS dysfunction, as well as cutaneous, pulmonary, and intestinal hemorrhages
- lose platelets
- Most get pneumonia
HME: Ehrlichia chaffeensis - diagnosis/treatment
-Diagnosis:
Detection of morulae in blood smear – rare
Serological and molecular techniques
-Treatment: Doxycycline
Coxiella burnetii - disease name? organism details?:
Q FEVER
- Small Gram-negative pleomorphic bacterium
- Two phases / forms: small-cell variant (become large-cell and then divide into small again) & large-cell variant (endospores - survive in environemnt)
- Obligate intracellular bacteria
- Reside and replicate in fully acidified phagolysosomes
Q (QUERY) FEVER - distribution, VECTOR FOR HUMANS/NONHUMANS:
- everywhere
- TICKS FOR NONHUMANS
- DOGS/CATS FOR HUMANS - in the amniotic fluid/placenta/feces
- in unpastuerized dairy
Q (QUERY) FEVER - primary mode of infection? resulting infection types?
- inhalation of Coxiella burnetii spores -
- Acute or a chronic infection
Q (QUERY) FEVER - presentation/syptoms acute
- Generalized disease resembling influenza
- Incubation period of 2-4 weeks
- Followed by the development of fever, chills, malaise, arthralgias, myalgias, severe headache, and photophobia
- Pneumonia may develop
- Abnormal liver function, CNS dysfunction, and vascular inflammation may be present
- The fever typically last 1 or 2 weeks, but it may take months for the patient to fully recover.
- Infection during pregnancy may lead to premature birth, abortion, or still birth
Q (QUERY) FEVER - presentation/syptoms chronic
- Appears mainly as endocarditis or hepatitis
- Acute signs of infection are generally absent
- Incubation period may be months to years
Q (QUERY) FEVER - diagnosis/treatment/prevention
-Diagnosis: molecular and serological techniques
-Treatment: Doxycycline
-Prevention:
inactivated whole cell vaccine
use is limited to high risk individuals, primarily laboratory workers
Bartonella - organism details, disease name, where do these orgnaims live in the human?
==Trench Fever
- Small slightly curved Gram-negative rods
- Can be grown in the laboratory (agar plates)
- require CO2
- may take weeks to produce colonies
- reside within erythrocytes.
trench fever - organism, vector, disease associations and among who in population
- Bartonella quintana
- human body louse
- Associated with poverty, lack of hygiene, and overcrowding
- observed in the homeless population
trench fever - mode of infection
-The organism is present in the feces of lice and is introduced into the bite by scratching
Trench Fever - disease presentation
- relapsing attacks of fever, headache, and dizziness that last 1-3 days
- “shin pain”
- recur every 4-6 days
- not considered fatal
Trench Fever - dianosis/treatment
-Diagnosis Serology Isolation of organism from blood May take weeks -Treatment and Prevention: gentamicin and/or erythromycin
Cat Scratch Fever - causative organism? seem among who in the population?
- Bartonella henselae
- children and adolescents
Cat Scratch Fever - infection process
- Bartonella henselae
- Organism can be found in cats and fleas (feces)
- Flea bites are thought to transmit disease among cats
- Human infection occurs when dried flea feces is introduced into man through cat scratches and bites
- More than 90% of infected individuals are able to recall a recent history of cat bites or scratches
Cat Scratch Fever - disease presentation
- Fever and a lymphadenopathy in the region of the inoculation
- A papule may develop at the site of inoculation
- Symptoms generally resolve without complication
Cat Scratch Fever -diagnosis/treatment
- Diagnosis: cultivation, serology and molecular analysis
- Treatment: Not necessary of effective
BACILLARY ANGIOMATOSIS - infection with what organism causes? what is it? WHo is this disease common among?
- B. henselae and B. quintana
- Vascular proliferative disease involving the skin
- Can spread to other organs such as liver, spleen bone marrow and lymph nodes
- HIV INFECTED INDIV
- Lesions appear bright red and are similar in appearance Kaposi-sarcoma lesions
Rocky Mountain spotted fever - organism cause, rash?
Rickettsia rickettsii
centripital spread rash
Rickettsial pox - organism cause, rash?
- rickettsia akari
- generalized rash
Louse-borne (epidemic) typhus fever - organism cause, rash?
- rickettsia prowazekii
- cetrifugal spread
Trench fever - organism cause, rash?
- bartonella quintana
- NO RASH
Q fever - organism cause, rash?
coxiella burnetii
NO RASH
Cat scratch fever - organism cause, rash?
bartonella henselae
papule at inoculation site
Human ehrlichiosis - organism cause, rash?
- ehrlichia and anaplasma
- 1/3 have rash
all rickettsia and rickettsia like orgnaims sgram stain???
GRAM NEGATIVE! AND INTRACELLULAR
distinct growth feature of ehrlichia and anaplasma?
morulae - vacuole bound colonies where tehy replicate - ALL INTRACELLULAR
shin pain with which organism/dosease?
trench fever-bartonella quintana
