Download Bordetella (pertussis) (whooping cough) bacterial respiratory

Bordetella
(pertussis)
(whooping cough)
bacterial respiratory childhood
infections
B . Pertussis
B . parapertussis
B .pertussis
Small gram-negative bacilli
 Most fastidious
 Culture media containing charcoal

◦ bordet-Gengou medium
◦ Charcoal blood agar
Strict aerobe
 Slow growth (3 days)
 3 major agglutinogens ( attachment )
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(1, 2 and 3)
detected by specific antiserum
Role in immunity
Three serotypes
 Type 1,2
 Type1,3
 Type 1,2,3
pathogenesis

Non invasive infection of respiratory mucosa
◦ Ciliated epithelium of bronchi , trachea
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Human is the only natural host
IP : 1 – 2 weeks
Tracheal cytotoxin ( TC )
Pertussis toxin (PT)
◦ Lymphocytosis
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Filamentous haemagglutnin (FHA)
clinical
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Catarrhal phase ( preventable )-most infectious
Paroxysmal phase ( sever cough)
Convalescent phase
Atypical cases
Complications
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Bronchopneumonia
Secondary infection
Lung collapse
Anoxia , convulsions
EPIDEMIOLOGY

SOURSE
◦ Patients ( droplets ) – child or adults
◦ Atypical cases
Cmunicable
 Epidemics
 Antibiotics reduce transmission
 Incidence and mortality

◦ All ages
◦ Cause of death ( < 2 years , infants )
Immunity

One attack confers long lasting immunity
◦ (herd immunity)
Infection with different serotype
 Passive protection from mother is
incomplete
 3 – injections of vaccine – effective active
immunity

Diagnosis
Clinical
 lymphocytosis
 Laboratory
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Nasopharynx (postnasal swab )
Pernasal swab
Selective media
Slid agglutinations ( antiserum)
Treatment
No effect in well established infection
 Erythromycin

◦ Reduce severity if given before paroxysmal
phase
◦ For 14- days
◦ Reduces transmission
◦ Prophylaxis of contacts
Control

Vaccination is safe - > 90% effective
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
Whole bacterial cell ( killed) – deep IM inj.
Contain 3 – agglutinogens
3 – doses
SE : neurological sequelae , crying , fever
Acellular pertussis vaccine
◦ PT , FHA + agglutinogens