Download presentation
Presentation is loading. Please wait.
Published byLeonard Pitts Modified over 9 years ago
1
Bordetella (pertussis) (whooping cough) bacterial respiratory childhood infections B. Pertussis B. parapertussis
2
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 ) ◦ (1, 2 and 3) ◦ detected by specific antiserum ◦ Role in immunity ◦ Three serotypes Type 1,2 Type1,3 Type 1,2,3
3
pathogenesis Non invasive infection of respiratory mucosa ◦ Ciliated epithelium of bronchi, trachea Human is the only natural host IP : 1 – 2 weeks Tracheal cytotoxin ( TC ) Pertussis toxin (PT) ◦ Lymphocytosis Filamentous haemagglutnin (FHA)
4
clinical Catarrhal phase ( preventable )-most infectious Paroxysmal phase ( sever cough) Convalescent phase Atypical cases Complications ◦ Bronchopneumonia ◦ Secondary infection ◦ Lung collapse ◦ Anoxia, convulsions
5
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 )
6
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
7
Diagnosis Clinical lymphocytosis Laboratory ◦ Nasopharynx (postnasal swab ) ◦ Pernasal swab ◦ Selective media ◦ Slid agglutinations ( antiserum)
8
Treatment No effect in well established infection Erythromycin ◦ Reduce severity if given before paroxysmal phase ◦ For 14- days ◦ Reduces transmission ◦ Prophylaxis of contacts
9
Control Vaccination is safe - > 90% effective ◦ Whole bacterial cell ( killed) – deep IM inj. ◦ Contain 3 – agglutinogens ◦ 3 – doses ◦ SE : neurological sequelae, crying, fever Acellular pertussis vaccine ◦ PT, FHA + agglutinogens
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.