title: Stunting correlates with high salivary and serum antibody levels after 13-valent pneumococcal conjugate vaccination of Venezuelan Amerindian children.
abstract: OBJECTIVE
  To determine the impact of pre-vaccination nutritional status on vaccine responses in Venezuelan Warao Amerindian children vaccinated with the 13-valent pneumococcal conjugate vaccine (PCV13) and to investigate whether saliva can be used as read-out for these vaccine responses.
  
  
  METHODS
  A cross-sectional cohort of 504 Venezuelan Warao children aged 6 weeks - 59 months residing in nine geographically isolated Warao communities were vaccinated with a primary series of PCV13 according to Centers for Disease Control and Prevention (CDC)-recommended age-related schedules. Post-vaccination antibody concentrations in serum and saliva of 411 children were measured by multiplex immunoassay. The influence of malnutrition present upon vaccination on post-vaccination antibody levels was assessed by univariate and multivariable generalized estimating equations linear regression analysis.
  
  
  RESULTS
  In both stunted (38%) and non-stunted (62%) children, salivary antibody concentrations correlated well with serum levels for all serotypes with coefficients varying from 0.61 for serotype 3-0.80 for serotypes 5, 6A and 23F (all p < 0.01). Surprisingly, higher serum and salivary antibody levels were observed with increasing levels of stunting in children for all serotypes. This was statistically significant for 5/13 and 11/13 serotype-specific serum and saliva IgG concentrations respectively.
  
  
  CONCLUSIONS
  Stunted Amerindian children showed generally higher antibody concentrations than well-nourished children following PCV13 vaccination, indicating that chronic malnutrition influences vaccine response. Saliva samples might be useful to monitor serotype-specific antibody levels induced by PCV vaccination. This would greatly facilitate studies of vaccine efficacy in rural settings, since participant resistance generally hampers blood drawing.
authors.affiliation: Laboratorio de Tuberculosis, Instituto de Biomedicina, Universidad Central de Venezuela, Caracas, Venezuela; Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands; Wilhelmina Children's Hospital, Utrecht, The Netherlands. Electronic address: L.M.Verhagen-4@umcutrecht.nl.
authors.forename: Lilly M
authors.initials: LM
authors.lastname: Verhagen
authors.affiliation: Department of Pathology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Meyke
authors.initials: M
authors.lastname: Hermsen
authors.affiliation: Laboratorio de Tuberculosis, Instituto de Biomedicina, Universidad Central de Venezuela, Caracas, Venezuela.
authors.forename: Ismar
authors.initials: I
authors.lastname: Rivera-Olivero
authors.affiliation: Laboratorio de Tuberculosis, Instituto de Biomedicina, Universidad Central de Venezuela, Caracas, Venezuela.
authors.forename: María Carolina
authors.initials: MC
authors.lastname: Sisco
authors.affiliation: Center for Infectious Disease Control, National Institute of Public Health and the Environment, The Netherlands.
authors.forename: Elena
authors.initials: E
authors.lastname: Pinelli
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Peter W M
authors.initials: PW
authors.lastname: Hermans
authors.affiliation: Center for Infectious Disease Control, National Institute of Public Health and the Environment, The Netherlands.
authors.forename: Guy A M
authors.initials: GA
authors.lastname: Berbers
authors.affiliation: Laboratorio de Tuberculosis, Instituto de Biomedicina, Universidad Central de Venezuela, Caracas, Venezuela.
authors.forename: Jacobus H
authors.initials: JH
authors.lastname: de Waard
authors.affiliation: Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Marien I
authors.initials: MI
authors.lastname: de Jonge
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood* / Q000737:chemistry; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006130:Growth Disorders / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000737:chemistry; D007223:Infant; D016014:Linear Models; D008297:Male; D044342:Malnutrition / Q000276:immunology; D009752:Nutritional Status; D011008:Pneumococcal Infections / Q000517:prevention & control; D022242:Pneumococcal Vaccines / Q000008:administration & dosage*; D012463:Saliva / Q000737:chemistry*; D065288:Serogroup; D013296:Streptococcus pneumoniae / Q000145:classification; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000627:therapeutic use; D014687:Venezuela
chemical_list: C538862:13-valent pneumococcal vaccine; D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate
keywords: 13-Valent pneumococcal conjugate vaccination; Chronic malnutrition; Indigenous children; Saliva; Venezuela