26 – Taylorella and Bordetella Flashcards
Microbiological characteristics
- Small gram-NEGATIVE cocco-bacilli
- Biocontainment level 2
- *Taylorella equigenitalis is notifiable in Canada
Microbiological characteristics of Taylorella
- Carboxyphilic
- Facultative anaerobe
Microbiological characteristics of Bordetella
- Obligate aerobes
- Non-fermentable
- *HIGHLY CONTAGIOUS
Taylorella natural host or habitat
- Host associated
- In equine genital tract
- Do NOT survive well in environment
Bordetella natural host or habitat
- Respiratory tract of many species
o Healthy and diseased animals - Pigs, dogs, rabbits, people
- *B. bronchiseptica also has an environmental reservoir in amoeba
- Do NOT survive well in environment
Virulence factors of Bordetella
- Adenylate cyclase haemolysin
- **Dermonecrotic toxin
- Fimbriae
- Tracheal cytotoxin
- Typer III secretion system
- **Pertussis Toxin (B. pertussis)
Dermonecrotic toxin of Bordetella
- Amount of toxin produced may be related to strain VIRULENCE
- Inhibitory towards porcine osteoblasts (atrophic rhinitis)
- Also required for B. avium to be pathogenic
B. pertussis: Pertussis Toxin
- *believed to be responsible for WHOOPING COUGH
- Composed of 5, 2-part subunits (A, B)
- Leads to increased cAMP levels
o Affects cells signalling - Has systemic effects: increased insulin
- Inhibits recruitment of WBCs and affects chemokine production
o Interferes with innate response
What does T. equigenitalis cause in horses?
- Contagious equine metritis
- Venereal disease in horses
o Natural mating or AI - *T. asinigenitalis rarely associated with similar infections
- *NOTIFICABLE DISEASE (CFIA)
T. equigenitalis in mares
- Vaginal discharge 2-7 days after bredding
- Return to estrous
T. equigenitalis in stallions
- Doesn’t typically result in clinical disease: SILENT carriers
- Found in smegma accumulating in urethral fossa
What is the treatment of T. equigenitalis?
- Antimicrobials
- Daily cleansing of vulva and clitoris
o Including clitoral fossa=important site of carriage
How can you control T. equigenitalis?
- Careful selection of studs
- Screening fo stallions
- Import controls
- *if importing from endemic region=tested and quarantined
What does B. avium cause in turkeys?
- Turkey Coryza: disease of upper respiratory tract
o Sneezing (called snick)
o Nasal discharge (mucoid, tenacious exudate)
o Altered vocalization
o Mouth breathing
B. avium causing Turkey Coryza
- highly infectious: up to 100% of flock affected
- affects young birds (<4weeks)
o if see high proportion sneezing=highly suggestive! - 7-10 day incubation
- *low mortality: may be up to 40% if secondary invaders
How is B. avium transmitted?
- Direct contact
- Contaminated feed, water, litter
- *survives in environment for 1-6 months!
- Can affect chickens=less severe
How do you treat B. avium in turkeys?
- Antimicrobials (tetracyclines)
How do you control B. avium in turkeys?
- Vaccinations
- Biosecurity
What is B. bronchiseptica associated with in pigs?
- Infections of respiratory tract in young pigs
o Pneumonia
o Atrophic rhinitis
What are the 2 things that cause atrophic rhinitis?
- Complex of P. multocida type D (PM)
- A and B bronchiseptica (BB)
How does atrophic rhinitis occur?
- BB starts infection, causing damage which allows PM to proliferate
- Toxins produced by PM cause epithelial hypoplasia, atrophy of mucous glands, osteolysis
- Dermonecrotic inhibits osteoblasts
- *ultimately result in atrophy of nasal turbinate’s and shrinking snout
What does B. bronchiseptica cause in dogs?
- Kennel cough! (canine infectious tracheobronchitis)
- *often polymicrobial
What are the ACUTE onset clinical signs that are seen with B. bronchiseptica in dogs?
- Paroxysmal: productive cough with retching
- Swollen vocal cords resulting in unusual sounding cough=honk
B. bronchiseptica in dogs
- Usually self limiting
- Incubation period of 3-10 days
- *very contagious: ISOLATE
- Clinically inapparent infections VERY common
- Long-term subclinical infections
- *can be difficult to clear even with antimicrobials
What is an important part of the diagnosis for Kennel cough?
- Patient history
o Lack of vaccine in past 6 months
o Contact with other dogs
How do you treat B. bronchiseptica in dogs?
- Antimicrobials in severe case (DOXYCYCLINE)
- *supportive therapy
o Anti-inflammatory
o Antitussives
o Bronchodilators
What are the vaccines available for B. bronchiseptica in dogs?
- Modified live: intranasal
o Triggering immunity right where the organism is going to infect them
o Risk of return to virulence
o Low virulence strain could cause disease in an immunocompromised person or animal - Whole cell and antigen extract: subcutaneous
- Modified live: oral
- *also vaccines for other respiratory pathogens may reduce severity of disease (DA2PP): includes parainfluenza
B. bronchiseptica in cats
- less common
- may be associated with contact with infected dogs
- disease more sever in young kittens
- treatment: doxycycline
What are the clinical signs in cats with B. bronchiseptica?
- Sneezing
- Mucopurulent nasal and ocular discharge
- *often mild compared to dogs
- COUGH is UNCOMMON
B. bronchiseptica in rabbits
- Similar to what is seen with P. multocida
o Rhinitis
o Pneumonia
o Otitis media/interna - *very common rabbits with respiratory disease
B. bronchiseptica in guinea pigs
- ONE OF THE MOST SUSCEPTIBLE SPECIES TO BORDETELLA INFECTIONS
o More likely to lead to serious disease, than carrier state - Acute rapidly progressive respiratory infections with HIGH mortality rate
- *rabbits can serve as a reservoir
B. pertussis in humans
- Whooping Cough: Most commonly children
o 3 phases of disease progression - Atypical pertussis in adults
o High density populations: students - Globally 350,000 deaths annually
- Highly contagious
- Vaccines available
What are the 3 phases of whooping cough disease progression in humans?
- Prodromal phase
- Paroxysmal phase
- Convalescent phase
Prodromal phase of whooping cough in humans
- Cold or flu like illness
Paroxysmal phase of whooping cough in humans
- Begins 7-14 days after prodromal phase
- Coughing paroxysms, followed by desperate gasps for air
- Paroxysms often followed by cyanosis and vomiting
Convalescent phase of whooping cough in humans
- Within 4 weeks of onset
- Decreased occurrence of paroxysms
Sample collection for Taylorella equigenitalis
- Swabs or biopsies
o Mares: cervix, uterus, clitoral fossa
o Stallions: urethra, urethral fossa, prepuce
Sample handling for Taylorella equigenitalis
- CRITICAL
- Don’t disinfect tissue before collection
- Collect samples before antimicrobials administered
- False negatives can be a big challenge
Sample collection of Bordetella spp
- Nasal or tracheal swab
- Do NOT use cotton swabs
o Cotton can be toxic to them and reduce likelihood of recovery - Bronchoalveolar lavage
- Transtracheal wash
Sample handling of Bordetella spp.
- Transport media important
- Do NOT freeze
Lab ID of Taylorella
- Culture
- May not be well IDed by Maldi-Tof
- PCR of cultures or clinical samples
Lab ID of Bordetella
- Culture
o Blood and chocolate agar - Serology
- Fluorescent Ab test on tissue sections
Taylorella: zoonotic/interspecies transmission
- ONLY causes clinical disease in EQUIDS
Bordetella: zoonotic/interspecies transmission
- Should ALL be considered POTENTIALLY ZOONOTIC
- B. bronchiseptica isolated form respiratory tract of people including whooping cough like illness
o Presumed to be zoonotic
o Can be pathogenic in compromised patients (children, chronic alcoholics, AIDS, acute leukemia)
o *sick from dog with attenuated-live vaccine
Treatment of Taylorella
- Antimicrobials to eliminate
o Many are effective - No guidelines for conducting or interpreting antimicrobial susceptibility
Treatment of Bordetella
- Susceptibility to antimicrobials varies
o Widespread CEPHALOSPORIN RESISTANCE - TETRACYCLINES typically treatment of choice
