title: Detection of Bordetella pertussis using a PCR test in infants younger than one year old hospitalized with whooping cough in five Peruvian hospitals.
abstract: OBJECTIVE
  To report the incidence, epidemiology, and clinical features of Bordetella pertussis in Peruvian infants under 1 year old.
  
  
  METHODS
  A prospective cross-sectional study was conducted in five hospitals in Peru from January 2010 to July 2012. A total of 392 infants under 1 year old were admitted with a clinical diagnosis of whooping cough and tested for B. pertussis by PCR.
  
  
  RESULTS
  The pertussis toxin and IS481 genes were detected in 39.54% (155/392) of the cases. Infants aged less than 3 months were the most affected, with a prevalence of 73.55% (114/155). The most common household contact was the mother, identified in 20% (31/155) of cases. Paroxysm of coughing (89.03%, 138/155), cyanosis (68.39%, 106/155), respiratory distress (67.09%, 104/155), and breastfeeding difficulties (39.35%, 61/155) were the most frequent symptoms reported.
  
  
  CONCLUSIONS
  An increase in pertussis cases has been reported in recent years in Peru, despite national immunization efforts. Surveillance with PCR for B. pertussis is essential, especially in infants less than 1 year old, in whom a higher rate of disease-related complications and higher mortality have been reported.
authors.affiliation: Instituto Nacional de Salud del Niño, Breña, Lima, Peru.
authors.forename: María Esther
authors.initials: ME
authors.lastname: Castillo
authors.affiliation: Hospital de Emergencias Pediátricas, La Victoria, Lima, Peru.
authors.forename: Carlos
authors.initials: C
authors.lastname: Bada
authors.affiliation: Hospital Edgardo Rebagliati Martins, Jr, Jesús María, Lima, Peru.
authors.forename: Olguita
authors.initials: O
authors.lastname: Del Aguila
authors.affiliation: Centro de Investigación de la Facultad de Ciencias de la Salud, Universidad Peruana de Ciencias Aplicadas, Av. San Marcos cuadra 2, Chorrillos, Lima, Peru.
authors.forename: Verónica
authors.initials: V
authors.lastname: Petrozzi-Helasvuo
authors.affiliation: Centro de Investigación de la Facultad de Ciencias de la Salud, Universidad Peruana de Ciencias Aplicadas, Av. San Marcos cuadra 2, Chorrillos, Lima, Peru.
authors.forename: Verónica
authors.initials: V
authors.lastname: Casabona-Ore
authors.affiliation: Hospital de Emergencias Pediátricas, La Victoria, Lima, Peru.
authors.forename: Isabel
authors.initials: I
authors.lastname: Reyes
authors.affiliation: Centro de Investigación de la Facultad de Ciencias de la Salud, Universidad Peruana de Ciencias Aplicadas, Av. San Marcos cuadra 2, Chorrillos, Lima, Peru. Electronic address: jdelvall@upc.edu.pe.
authors.forename: Juana
authors.initials: J
authors.lastname: Del Valle-Mendoza
mesh_terms: D001886:Bordetella pertussis / Q000235:genetics*; D003430:Cross-Sectional Studies; D005260:Female; D006761:Hospitals; D006801:Humans; D007114:Immunization; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010567:Pertussis Vaccine / Q000276:immunology; D010568:Peru / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D014611:Vaccination; D014917:Whooping Cough / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control*
chemical_list: D010567:Pertussis Vaccine
keywords: Bordetella pertussis; PCR; Peru; Whooping cough