Zoonotic Infections Flashcards
Tick vectored pathogens
Erlichia
Borrelia
Rickettsia
Anaplasma
Babesia
Bartonella species and the associated infections
bartonella henselae: Cat-scratch fever
Bartonella Quintana: trench fever, bacillary angiomatosis, SBE
Bartonella bacilliformis: bartonellosis/ Oriya fever, verruga
Bartonella Elizabethae: endocarditis
Bartonella characteristics
Small gram-negative aerobic bacilli
Intracellular pathogen in blood and RES
Motility is variable based on species
- B. Bacilliformis is only in south america*
- B. Henselae is the most common cat infection*
Transmission of bartonella
Bite by arthropod for all except B. Henselae
Bite/scratch by a cat for B hensalae
- causes by flea feeces under the cat claws/ surrounding teeth
highest risks include cat contact, immunocompromised and poor hygiene
Bartonellosis due to B. Bacilliformis
Oroya fever
Vector is the sandfly bite
Multiplication occcurs in bloodstream and increases RBC fragility intravascular hemolysis
Oroya fever specifically disables clearance of RBCs
Symptoms:
- fever, malaise, myalgia and headache
- rapidly worsening anemia
Bartonellosis due to B. Bacilliformis
Verruga
Worsen of oroya fever
- produces red-purple skin lesions that look like warts and persists for months/years
Trench fever (B. Quintana)
Vector is body lice
Bacteria survive and multiply in RES cells
Symptoms:
- severe headache
- sudden undulating onset fever (recurrence is 5 days)
- weakness
- rashes
- osteomyalgia in long bones
B. Henselae infections (cat-scratch fever
Vector is cat scratch/bite
Bacteria infects RES cells and lymph nodes
Bacterial/septicemia occur in immunocompromised hosts ( really bad)
Is usually benign in children
Symptoms:
- cardinal sign is massively swollen sentinel lymph node to the site of scratch/bite*
- mild fever and malaise
- severe cases causes bacillary angiomatosis
Bacillary angiomatosis
Lesions in the skin, liver, lymph nodes and spleen
- most common in immunocompromised patients and is a result of untreated cat scratch fever.
Diagnosis of bartonella
- super challenging to culture*
- usually diagnosed via DFA /IFA (assays)
Pasteurella multocida
Dog and cate bites are vectors
Gram negative coccobacilli
- oxidase and catalase (+)
- aerobic or facultative aerobe
often presents with cellulitis with onset redness, pain, swelling and low grade fevers
Leptospirosis interrogans
Animal urine (Specifically in rat and dog owners)
Spirochete (spiral shaped) bacteria!
Causes two main diseases
-leptospirosis: fever chills, headache, vomiting, rash (mild)
- Weil disease (icterohemorrhagic leptopirosis)
- jaundice, conjunctival injection(blood in eyes)
* causes liver and kidney failure if not treated)
(Major)
Tick infection (Ixodes)
Causes three diseases
Lyme disease
Anaplasmosis
Babesiosis
eastern ticks are more infectious than western (idopathically known)
Borrelia burgdorferi (Lyme disease)
Spirochete bacteria that causes Lyme disease
3 stages: 3 days- 4 weeks
early localization:
- bullseye rash (erythema migrants)
- flulike symptoms and malaise
Early disseminated: weeks- months
- arthralgia and arthritis
- Bell’s palsy (facial nerve palsy) radicuolpathy
Late chronic: months-years after untreated infection
- chronic skin, nervous system and joint issues
Canine sentinel map
Used to determine where human outbreaks are likely since dogs are the most common host of Lyme disease.
- if dog rates go up somewhere, it is likely human rates will as well
Relapsing fever
Transmitted by body lice and is from other borrelia species
- incubate for 3-10 days and then produces sudden fever/chills
- fever persists for 3-5 days w/ febrile stages lasting 4-10 days
- followed by another fever and continues this pathogenesis for 3-10 times
Anaplasma phagocytophilum
Human granulocyte anaplamosis
- obligate gram-negative intracellular bacteria
- infects leukocytes and erythrocytes and appears like a huge granule (morula)*
Rarely severe of fatal and shows up with flulike symptoms
- sometimes presents in conjunction with limes disease
Babesiosis
Babesia Microti is the most common pathogen
presents with Maltese cross or “ring cells”in blood cells (similar to malaria)
Tick is vector and presents with flu like symptoms after 7-10 days
Can also be mistaken with P. Falciparum diseases
Dangerous in elderly and young
Erlichia Chaffeensis
Lone star tick is vector
Produces human monocyte erlichiosis
also produces modular and maltease cross, usually in monocytes over granulocytes
Is more severe and fatal than normal ticks
- presents flulike symptoms but fever is out of control if not treated
Rickettsia rickettsii
- produces Rocky Mountain spotted fever*
- most serious tick-Bourne disease and is 50% fatality
- rash most common on feet and hands begins 2-4 days after flulike fever and symptoms*
- rash is systemic in organs on top of skin
Vasculitis occurs everywhere and is characterized by lymphocyte-surrounded vasculature
- produces infected cells that swell and necrosis ad well as thrombosis of vessels
Difference between R. Prowazekii and R. Typhi
Prowazekii:
- vectored by human lice
- epidemic typhus and 6-30% fatal cases
Typhi:
- vectored by fleas
- endemic typhus but rarely fatal
Both produce rashes that spares palms and soles, unlike rocky mountain
Both produce flulike symptoms and both dont stain well in gram stains
- gram negative and intracellular coccobacilli
Both need giemsa stain in order to visualize easier
