title: Heterologous and sex differential effects of administering vitamin A supplementation with vaccines.
abstract: WHO recommends high-dose vitamin A supplementation (VAS) to children from 6 months to 5 years of age in low-income countries, in order to prevent and treat vitamin A deficiency-associated morbidity and mortality. The current policy does not discriminate this recommendation either by sex or vaccination status of the child. There is accumulating evidence that the effects of VAS on morbidity, mortality and immunological parameters depend on concomitant vaccination status. Moreover, these interactions may manifest differently in males and females. Certain vaccines administered through the Expanded Program on Immunization have been shown to alter all-cause mortality from infections other than the vaccine-targeted disease. This review summarizes the evidence from observational studies and randomized-controlled trials of the effects of VAS on these so-called heterologous or non-specific effects of vaccines, with a focus on sex differences. In general, VAS seems to enhance the heterologous effects of vaccines, particularly for diphtheria-tetanus-pertussis and live measles vaccines, where some studies, although not unanimously, show a stronger interaction between VAS and vaccination in females. We suggest that vaccination status and sex should be considered when evaluating the effects of VAS in early life.
authors.affiliation: Research Center for Vitamins & Vaccines (CVIVA), Bandim Health Project, Statens Serum Institut, DK-2300 Copenhagen S, Denmark Projécto de Saúde Bandim, Indepth Network, Apartado 861,Codex 1004, Bissau, Guinea-Bissau.
authors.forename: Kristoffer J
authors.initials: KJ
authors.lastname: Jensen
authors.affiliation: MRC Laboratories, Fajara, The Gambia.
authors.forename: Jorjoh
authors.initials: J
authors.lastname: Ndure
authors.affiliation: Vaccine and Infectious Diseases Laboratory, Department of Immunology, Monash University, 89 Commercial Road, Prahran, Victoria 3004, Australia.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Plebanski
authors.affiliation: Vaccine and Infectious Diseases Laboratory, Department of Immunology, Monash University, 89 Commercial Road, Prahran, Victoria 3004, Australia katie.flanagan@dhhs.tas.gov.au.
authors.forename: Katie L
authors.initials: KL
authors.lastname: Flanagan
mesh_terms: D001500:BCG Vaccine; D002648:Child; D002675:Child, Preschool; D003906:Developing Countries; D019587:Dietary Supplements; D015721:Diphtheria-Tetanus-Pertussis Vaccine; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D064789:Immunity, Heterologous / Q000187:drug effects* / Q000276:immunology; D007114:Immunization / Q000379:methods; D007223:Infant; D008297:Male; D008458:Measles Vaccine; D064887:Observational Studies as Topic; D016032:Randomized Controlled Trials as Topic; D012737:Sex Factors; D014801:Vitamin A / Q000008:administration & dosage* / Q000009:adverse effects; D014802:Vitamin A Deficiency / Q000188:drug therapy / Q000276:immunology* / Q000401:mortality
chemical_list: D001500:BCG Vaccine; D015721:Diphtheria-Tetanus-Pertussis Vaccine; D008458:Measles Vaccine; D014801:Vitamin A
keywords: All-cause mortality; BCG vaccine; DTP vaccine; Measles vaccine; Sex; Vitamin A