This retrospective pregnancy case was reported in a literature article and described the occurrence of pertussis in a infant exposed to dTpa vaccine in utero while the mother was treated. On an unknown date, the mother received dTpa vaccine at an unknown dose. The mother's last menstrual period was on an unknown date and estimated date of delivery was on an unknown date. The infant was diagnosed with pertussis (serious criteria GSK medically significant). On 14th March 2013, the infant experienced paroxysmal cough. In March 2013, the infant experienced apnea (serious criteria GSK medically significant) and post-tussive vomiting. On an unknown date, the infant experienced maternal vaccine exposure. The infant was treated with Azithromycin. On an unknown date, the outcome of the pertussis, paroxysmal cough, apnea and post-tussive vomiting were recovering/resolving and the outcome of the maternal vaccine exposure was unknown. It was unknown if the reporter considered the pertussis, paroxysmal cough, apnea and post-tussive vomiting to be related to dTpa vaccine. Additional information was provided: This retrospective pregnancy case was reported in a literature article and it described the occurrence of pertussis like symptoms in an 11-month-old infant of unspecified gender whose mother was vaccinated with unspecified Tdap vaccine (manufacturer unknown) during pregnancy. The patient had 3 older siblings who were approximately 11, 9 and 7 years old at the time of vaccine administration. They all lived together and the children were undervaccinated due to parental refusal; they had reportedly received 2, 1 and 3 doses of pertussis-containing vaccines respectively, although this could not be confirmed. No information on the mother's obstetric history, last menstrual period or estimated date of delivery date, gestation at the time of the administration of the vaccine, concurrent medical conditions, medical and family history or concomitant medication was provided. On an unspecified date, at an unspecified gestation, the mother reported receiving an unspecified Tdap booster vaccine (dosage was unknown; administration route and site were not unspecified; batch number was not provided). Please note that the authors commented that this administration could not be corroborated. No adverse event secondary to the administration of the vaccine was reported. The mother delivered a live male infant between April and May 2012. No information was provided regarding the delivery. The child had only been seen by his health care provider once between birth and 11 months of age and had not been vaccinated due to parental refusal. He developed prodromal pertussis symptoms on 4 March 2013 at 11 months of age, while the family was traveling out of state. Cough reportedly began on 14 March 2013, and he was brought to his health care provider 12 days later, on 26 March, with symptoms consistent with pertussis: paroxysmal cough, apnoea and post-tussive vomiting according to his parents. No coughing illness was reported among the siblings. The infant was not reported to have any pertussis associated complications after treatment (seizures, pneumonia, or encephalopathy) and had only light coughing on 11 April 2013. This case was considered medically relevant by GSK. No thoracic radiography was performed according to the authors. A nasopharyngeal swab specimen collected from the infant on 26 March 2013 was tested at a commercial laboratory and at the state public health laboratory. Both returned positive culture results for Bordetella pertussis. The isolate (designated I979) was forwarded to the Centers for Disease Control and Prevention for confirmatory identification and molecular typing as part of the Enhanced Pertussis Surveillance program and it was found to be both pertactin and pertussis-toxin deficient. The infant was prescribed 5-day course of oral azithromycin as treatment for the pertussis infection; but the parent reported that the infant received treatment for 3 consecutive days, beginning 26 March 2013. Outcome of the infant's pertussis infection was partial recovery at the time of reporting as he still had some light coughing on 11 April 2013. No adverse event secondary to the maternal exposure was reported, so no comment regarding causality was made. The authors concluded that "although incidence of combined pertactin and pertussis-toxin deficiency in Bordetella pertussis is rare, any increased mutation in these or other acellular vaccine immunogens may have serious implications for the efficacy of current vaccines. Global epidemiologic, culture-based, and molecular-based monitoring of Bordetella pertussis is critical for understanding current trends of the disease it causes".