Bordetella Flashcards
important species? disease?
Bordetella pertussis- whooping cough
Bordetella parapertussis- don’t understand much about this disease
morphology of B. pertussis?
Gram negative coccobacilli
no polysaccharide capsule
aerobes
B. pertussis epidemiology
high contagious
aerosol spread
mostly affects young children (can be fatal in infants)
adults infected with less severe symptoms
respiratory tract may be major reservoir
B. pertussis diagnosis techniques
PCR
serology
Whooping cough stages:
Catarrhal stage- cold like symptoms, infectious
paraoxysomal stage- severe cough paroxysomes, leukocytosis
Convalescent stage: chronic cough, bacteria absent
Pathogenesis of B. pertussis
inhale with aerosol droplets
adhere to respiratory ciliated epithelium
produce 3 toxins that cause pathogenic effects: Pertussis Toxin, Adenylate cyclase toxin, tracheal cytotoxin
Pertussis toxin
ADP ribosoyl transferase that modifies Gi protein (interferes with signal transduction)- same as Diphtheria toxin, just different target
inhibits innate immune system
responsible for systemic effects of disease (leukocytosis)
Tracheal cytotoxin action
damages and deciliates epithelial cells
it is a peptidoglycan fragment
Adenylate cyclase toxin
targets and inactivates neutrophils
B. pertussis treatment
Azithromycin or clarithromycin (if treated early enough)
usually by time patients present, bacteria are absent and antibiotics dont help
supportive therapy- nutrition, oxygen, hydration
anti-tussive (anti-cough) medications ineffective
have to wait it out
B. pertussis vaccines
DTP: whole cell vaccine
DTaP: acellular vaccine
Tdap: acellular vaccine
DTP vaccine
whole cell vaccine
waning by adulthood
reactogenic
DTaP Vaccine
acellular vaccine non-reactogenic give at 2,4,6,18 mo, 5 year, booster at 11-13 years for young children protection wanes after a few years
Tdap vaccine
new vaccine for adolescents and adults
