Bordetella of Corynebacteria Infections

 

Bordetella

 

 

Bordetella are minute aerobic gram-negative bacteria. B. pertussis is the causative agent of whooping cough. Pertussis has two phases. The first phase is an upper respiratory tract illness with fever, cough, and malaise. After a period of around 10 days, the second toxaemic phase develops, characterised by prolonged and paraxysmal coughing with inspiratory whoops. The coughing may be so severe that it leads to vomiting and aspiration. During the first phase, the organism can be readily recovered from respiratory secretions and the severity of the disease can be reduced by antimicrobial therapy. During the second phase of the disease, the organism is rarely recovered and antimicrobials do not alter the course of the disease.

       Laboratory diagnosis can be made by culturing nasopharyngeal secretions on Bordet-Gengou medium. B. pertussis is recovered in about 80% of cases in the first 2 weeks but rarely after 4 weeks of symptoms. Erythromycin given in the initial stage is effective in reducing the symptoms. An inactivated vaccine is available which is given as part of DPT at 2, 4, and 6 months of age.