title: The effect of vitamin A supplementation and diphtheria-tetanus-pertussis vaccination on parasitaemia in an experimental murine malaria model.
abstract: BACKGROUND
  Vitamin A supplementation (VAS) decreases overall child mortality in low-income countries. For logistical reasons, VAS has been linked to routine childhood immunizations. However, several recent studies have indicated that VAS may increase mortality and morbidity from infectious diseases when given with the diphtheria-tetanus-pertussis (DTP) vaccine. The immunological effects of combining the 2 treatments are unknown.
  
  
  METHODS
  We studied the effect of treating C57BL/6 mice with VAS and DTP, 1 week prior to infection with Plasmodium berghei ANKA. The progression of disease was monitored through parasite load and time to death.
  
  
  RESULTS
  We found significantly higher levels of parasitaemia in VAS/DTP-treated mice than in control mice (crude geometric mean parasitaemia ratio 2.02 (1.08-3.76), p = 0.03). There was no effect of administering either VAS or DTP alone, indicating that the increase in parasitaemia was due to a synergistic effect of VAS and DTP (p for interaction = 0.02). The effect of VAS/DTP on levels of parasitaemia was modified by the specific parasite variant used. No effect was observed on time to death.
  
  
  CONCLUSIONS
  Our results indicate that VAS/DTP can negatively influence the outcome of malaria infection in mice, adding to the concerns about simultaneous VAS and DTP administration to children in low-income, malaria endemic countries.
authors.affiliation: Bandim Health Project, INDEPTH Network, Statens Serum Institut, Copenhagen, Denmark. mjj@ssi.dk
authors.forename: Mathias Jul
authors.initials: MJ
authors.lastname: Jørgensen
authors.forename: Line
authors.initials: L
authors.lastname: Hein-Kristensen
authors.forename: Casper
authors.initials: C
authors.lastname: Hempel
authors.forename: Henrik
authors.initials: H
authors.lastname: Ravn
authors.forename: Lothar
authors.initials: L
authors.lastname: Wiese
authors.forename: Jørgen A L
authors.initials: JA
authors.lastname: Kurtzhals
authors.forename: Christine Stabell
authors.initials: CS
authors.lastname: Benn
mesh_terms: D000818:Animals; D004032:Diet / Q000009:adverse effects; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage* / Q000009:adverse effects*; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008288:Malaria / Q000401:mortality / Q000469:parasitology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018512:Parasitemia; D010962:Plasmodium berghei / Q000302:isolation & purification*; D016019:Survival Analysis; D014801:Vitamin A / Q000008:administration & dosage* / Q000009:adverse effects*
chemical_list: D015721:Diphtheria-Tetanus-Pertussis Vaccine; D014801:Vitamin A