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What is A child presents with complaints of cough. Characteristic inspiratory whoop present. He is not immunised. Sample for investigation is: and explain in detail?
a. Nasopharyngeal swab(Ref: Nelson's 20/e p 1377-1381, Ghai 8/e p 242-243)For diagnosis of Whooping cough isolation of B. pertussis in culture remains the gold standardThe specimen is obtained with deep nasopharyngeal aspiration or a swabCough plates and postnasal swabs are unsatisfactory because of overgrowth by commensal bacteriaDNA detection by PCR is replacing culture because of increased sensitivity & quicker results.