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What is Which of the following statements is true regarding pertussis - and explain in detail?
Pertussis (Whooping Cough):

Leukocytosis does not correlates with the severity of cough
Drug of choice: Erythromycin (40 mg/kg QID X 10 days)

Vaccines:

DPT:

i. Killed acellular bacilli 20,000 million per dose (0.5 ml)
ii. Pertussis component leads to neurological complications after 2 years of age (@ 1 per 1,70,000 vaccinees)
iii. Vaccine efficacy is 50 – 60 % (2 doses) and 70% (3 doses)
Pertussis killed whole cell vaccine

DOC for cases and contacts: Erythromycin (for 10 days)