Vitamin A supplementation enhances infants' immune responses to hepatitis B vaccine but does not affect responses to Haemophilus influenzae type b vaccine.
Vitamin A supplementation reduces child mortality and severe morbidity in less developed countries, and the Expanded Program on Immunization (EPI) offers an ideal opportunity to deliver supplements in developing countries. High-dose vitamin A supplementation has been shown to have no effect on the immunogenicity of oral polio vaccine, tetanus toxoid, pertussis, or on measles vaccine given at 9 mo, but a negative effect on measles vaccine administered at 6 mo and a potentiating effect on diphtheria vaccine. Its effect on the antibody response to hepatitis B and Haemophilus influenzae type b antigens has not yet been established. To assess these effects, the present trial was carried out in the Offinso district of Ghana; 1077 infants were enrolled shortly after birth and randomized either to receive or not to receive 15 mg retinol equivalent with vitamin A together with the pentavalent "diphtheria-polio-tetanus-Haemophilus influenzae b-hepatitis B" vaccine at 6, 10, and 14 wk of age. All mothers received a postpartum supplement of 120 mg retinol equivalent vitamin A as per national policy. Blood samples were taken from infants at 6 and 18 wk of age. The results are based on 888 infants (82.4%) who completed the trial. The vitamin A supplementation did not affect the immune response to Haemophilus influenzae type b, but there was a significant improvement in the immune response to hepatitis B vaccine (93.9 vs. 90.2%, P = 0.04). However, given the high percentage of infants with seroprotection in the control group, it is doubtful that inclusion of vitamin A in the EPI would be justified on these grounds alone.
Newton
Sam
S
Kintampo Health Research Centre, Kintampo, Ghana. sam.newton@ghana-khrc.org
Owusu-Agyei
Seth
S
Ampofo
William
W
Zandoh
Charles
C
Adjuik
Martin
M
Adjei
George
G
Tchum
Samuel
S
Filteau
Suzanne
S
Kirkwood
Betty R
BR
D000907:Antibodies, Bacterial / Q000096:biosynthesis*; D016667:Bacterial Capsules; D019587:Dietary Supplements; D018073:Haemophilus Vaccines / Q000276:immunology*; D019741:Haemophilus influenzae type b / Q000276:immunology*; D006510:Hepatitis B Antibodies / Q000096:biosynthesis*; D017325:Hepatitis B Vaccines / Q000276:immunology*; D006801:Humans; D007223:Infant; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D014801:Vitamin A / Q000494:pharmacology*
D000907:Antibodies, Bacterial; D018073:Haemophilus Vaccines; C044237:Haemophilus influenzae type b polysaccharide vaccine; D006510:Hepatitis B Antibodies; D017325:Hepatitis B Vaccines; D011135:Polysaccharides, Bacterial; D014801:Vitamin A