title: Prevalence of antibody to Bordetella pertussis in neonates and prevalence of recent pertussis infection in pregnant women in Catalonia (Spain) in 2003 and 2013.
abstract: BACKGROUND
  Infections because of Bordetella pertussis still occur in infants and adults in European countries, despite vaccination coverage against pertussis being high.
  
  
  METHODS
  IgG antibody titers to pertussis toxin (anti-PT) were assessed using an enzyme-linked immunosorbent assay test (Serion ELISA classic) in 353 cord blood samples from neonates of a representative sample of pregnant women obtained in Catalonia (Spain) in 2013. Neonates with anti-PT titers ≤ 40 international units (IU)/mL were considered to be unprotected against pertussis. IgG-PT titers >100 IU/mL in umbilical cord samples were considered to be indicative of a current or recent pertussis infection (12 months) in pregnant women. The age-standardized prevalence of recent pertussis infection obtained in this study was compared with the prevalence obtained in 2003.
  
  
  RESULTS
  The mean anti-PT titer in neonates was 10.8 IU/mL and 89.8% of neonates were unprotected against pertussis. The prevalence of unprotected neonates as defined by cord blood anti-PT ≤ 40 IU/mL was 90%. The prevalence of recent pertussis infection in pregnant women as defined by cord blood anti-PT >100 IU/mL was 2%. The diphtheria-tetanus-pertussis vaccination coverage during childhood in pregnant women was 75%. The age-standardized prevalence of recent pertussis infection in pregnant women observed in this study (2.2%) was slightly higher than the prevalence obtained in 2003 (1.5%), with an odds ratio = 1.45 (95% confidence intervals: 0.5-3.9), although differences were not statistically significant.
  
  
  CONCLUSIONS
  Most neonates are unprotected against pertussis and pertussis infections are frequent in pregnant women in Catalonia. Infants and pregnant women should be the priority population groups for pertussis prevention programs in Catalonia.
authors.affiliation: From the *Public Health Agency of Catalonia, Catalonia; †CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Madrid; ‡Obstetrics Service, Hospital Josep Trueta of Girona, Girona; §Instituto de Salud Carlos III, Madrid; ¶Preventive Medicine and Epidemiology Service, Hospital Vall d'Hebron of Barcelona; ‖Ginaecology and Obstetrics Service, Hospital del Mar of Barcelona; **Public Health Agency of Barcelona; ††Obstetrics Service, Hospital Vall d'Hebron of Barcelona; ‡‡Department of Public Health, University of Barcelona, Barcelona, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Plans
authors.forename: Elena
authors.initials: E
authors.lastname: Álvarez
authors.forename: Fernando
authors.initials: F
authors.lastname: de Ory
authors.forename: Magda
authors.initials: M
authors.lastname: Campins
authors.forename: Toni
authors.initials: T
authors.lastname: Payà
authors.forename: Pilar
authors.initials: P
authors.lastname: Balfagón
authors.forename: Pere
authors.initials: P
authors.lastname: Godoy
authors.forename: Joan
authors.initials: J
authors.lastname: Caylà
authors.forename: Ramon
authors.initials: R
authors.lastname: Carreras
authors.forename: Lluís
authors.initials: L
authors.lastname: Cabero
authors.forename: Angela
authors.initials: A
authors.lastname: Domínguez
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D001886:Bordetella pertussis / Q000276:immunology*; D015721:Diphtheria-Tetanus-Pertussis Vaccine; D005260:Female; D005312:Fetal Blood / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007231:Infant, Newborn; D008875:Middle Aged; D037342:Pertussis Toxin / Q000276:immunology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology*; D015995:Prevalence; D016036:Seroepidemiologic Studies; D013030:Spain / Q000453:epidemiology; D014611:Vaccination / Q000706:statistics & numerical data; D014917:Whooping Cough / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D015721:Diphtheria-Tetanus-Pertussis Vaccine; D007074:Immunoglobulin G; D037342:Pertussis Toxin