Bordetella Pertussis Flashcards
physical description of bordetella pertussis
- minute coccobaccillus
- gram negative
- encapsulated, non motile
- associated hemolysis
Clinical stages of Bordetella pertussis
- Incubation period; 1-2 wks
- Catarrhal stage
- Paroxysmal stage
- Convalescent stage
Clinical symptoms associated with each stage
- incubation; none
- catarrhal; low grade fever, runny nose, worsening cough
- paroxysmal; whooping cough, prolonged, vomiting, lymphotoxicity
- convalescent; cough less severe, 45 days
Complications that can follow bordetella pertussis
- bronchopneumonia
- encephalitis
Epidemiology of B. pertussis
- spread via droplets
- highly contagious
- catarrahal stage most contagious, but mild symptoms
People B. pertussis effects and where
- usually a disease of small children
- getting it confers immunity
- most dangerous for infants
- less booster immunity in adults and old children, present milder symptoms but still contagious
Pathogenesis of B. pertussis
- Fha; filamentous hemagglutinin; allows pertussis to bind to glycoproteins receptor on ciliated epithelium
- phagocytosed without activating macrophages
- aided by pili, pertactin surface protein, pertussis toxin
- ciliary stasis of mucocillary escalator
Description of the pertussis toxin
-AB5 toxin
-5 B parts bind to ganglioside specific for ciliated cells and phagocytes
-A part ADP-ribosylates an inhibitory Gprotein
-A prevents inactivation of adenyl cyclase(Inc. cAMP)
-not absolutely essential
Essentially, prevents GDP from being released to inactivate
Description of calmodulin-dependent adenyl cyclase
-additionally ACase; only active in eukaryotic cells
Description of dermonecrotic toxin
- role uncertain
- secreted by T3SS
Description of tracheal cytotoxin
- soluble PG residue
- kills ciliated epithelial cells
Description of LPS
-contain Lipid A and Lipid X
Control of B. pertussis
- vaccinate 3x before 1st birthday; DTap and booster with pertussis
- DTap; use of surface proteins
Medication for B. pertussis
-erythromycin/azithromycin
Description of B. parapertussis
- similar to whooping cough, but milder
- contains cryptic ptx operon but not expressed
