Immune response to Bordetella pertussis is associated with season and undernutrition in Senegalese children

Abstract

Background: While vaccines elicit a protective response in most recipients, studies suggest that environmental and nutritional factors can influence the strength of the individual response to immunization and to subsequent natural infectious challenges.

Methods: We conducted a longitudinal survey in Senegal to assess the individual response to B. pertussis, a respiratory disease against which Senegalese children are vaccinated before the age of one (Clinicaltrials.gov ID: NCT01545115). A cohort of 203 children aged 1-9 from four villages of the Senegal River Valley was followed-up for 14 months (October 2008-January 2010). During that period, four visits have been made to the villages to assess the immunological and nutritional status of these children and to determine risk factors involved in the modulation of their humoral immune response to B. pertussis toxin.

Results: A multivariate model has demonstrated that birth season and nutritional status appeared to modulate humoral response to pertussis toxin. Moreover, response to B. pertussis was dependent on age, village and time of visit.

Conclusions: These results are consistent with the hypothesis that environmental and nutritional factors modulate children's response to pertussis following natural infection or vaccination.

Keywords: Africa; Birth season; Bordetella pertussis; Environment; Immunity; Malnutrition.