1. ‫بسم ا الرحمن الرحيم‬
GENUS:
BORDETELLA
Prof. Khalifa Sifaw Ghenghesh

2. Small, Gram-negative coccobacilli
Strict aerobes.
X and V factors not required for
growth
Three species:
–B. pertussis,
–B. parapertussis
–B. bronchiseptica

3. Bordetella species

4. Bordetella bronchiseptica
Leifson flagella stain

5. Scanning electron micrograph of
Bordetella bronchiseptica

6. Bordetella pertussis
Whooping Cough
– Paroxysmal coughing
Require blood, or starch or
charcoal for growth
– Bordet-Gengou medium (BGM)
Strict aerobe
Optimal temp. > 35-36oC

7. ANTIGENICITY
3 Major Agglutinogens >1, 2 and 3
Detected by using adsorbed,
single-agglutinin sera
3 serotypes pathogenic to man
– Type 1,2
– Type 1,3
– Type 1,2,3
All 3 have a role in immunity

8. Virulence Factors
Pertussis toxin (PT): an exotoxin
which enters target cells and
activates their production of cAMP,
a molecule that acts as a second
messenger in cell protein synthesis
regulation
Tracheal cytotoxin: causes
ciliated epithelial cell destruction
Hemoagglutinin: a cell surface
protein which helps the bacterium
bind to the host cell surface

9. PATHOGENESIS
highly contagious bacterium
Non-invasive disease
Man > only natural host
Incubation period >> 1-2 weeks
Enters respiratory tract via
inhalation > binds to and
destroys the ciliated epithelial
cells of the trachea and bronchi.
Symptoms last for many weeks

10. LABORATORY DIAGNOSIS
1. Bacterial Culture:
Specimen:
– Pernasal swab on flexible wire
– Specimens on several successive days>
higher isolation rates.
– Transport media should not be used
Culture:
– Immediately on BGM
– Incubate for at least 1 week
Identification:
– Serological

11. 2. Detection of Bacterial Antigens
Bordetella antigens in serum and
urine using specific antiserum
Immunofluorescence Technique:
– Bacteria in nasopharyngeal
secretions labelled with fluoresceinconjugated antiserum > examined
with ultraviolet microscopy.
3. Detection of Bordetella
Antibody:
Sera and nasopharyngeal secretions
examined for Ab > Agglutination
Tests, ELISA

12. Bordetella pertussis

14. TREATMENT
Erythromycin
–For 2 weeks
–May reduce the severity of
illness if given before
paroxysmal stage.
–No clinical effect when the
infection is established
–May be given to protect nonvaccinated infants

15. CONTROL
Vaccination:
– Safe and >90% effective.
– Adsorbed vaccine (i.e. with adjuvant).
- Contains all 3 agglutinogens.
- Minimum 3 doses.
- Minor adverse reactions:
- Erythema and local swelling, slight
feverishness
- Possible neurological sequelae
- Acellular pertussis vaccine

16. Bordetella parapertussis
–a respiratory pathogen that can
cause mild pharyngitis.
Bordetella bronchiseptica
–a cause of pneumonia, otitis
media, and other respiratory
infections in animals.