A variety of antimicrobial agents have been used to treat children with pertussis to decrease the excretion of Bordetella pertussis and we hope prevent transmission of the infection to other children.1-5 Erythromycin is considered the drug of choice for B pertussis infections by the American See also p 520. Academy of Pediatrics Committee on Infectious Disease because of its low toxicity and superior efficacy in eradicating this organism from the nasopharynx when compared with other antimicrobial agents.3-7
We report the failure of seven days of erythromycin therapy to eradicate B pertussis from the pharynx of an infant. A second infant who was exposed to this child also contracted pertussis in spite of prophylactic use of erythromycin.
Bacteriologic Methods.—Nasal washing specimens were cultured and examined by direct fluorescent antibody (FA) techniques. Fresh control slides were prepared for each FA examination using stock B pertussis and B parapertussis cultures.