Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
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PMID:Vitamin A supplementation enhances infants' immune responses to hepatitis B vaccine but does not affect responses to Haemophilus influenzae type b vaccine. 1744 92

Vaccines are usually assessed by analyses of their safety and immunogenicity to determine the effectiveness of eliciting antibody responses against target organisms. However, it is equally important to establish antibody affinity because of its specific role in protection from infection. Antibody affinity can be determined by comparisons of various antibody concentrations in dose-response curves. During a study on the immunogenicity of a pentavalent vaccine in 888 infants, antibody affinity analyses of the hepatitis B and Haemophilus influenzae type b components were investigated in infants given 15mg RE vitamin A with their vaccination and those who were not given vitamin A. In this paper we present the results of 222 infants; a 25% sub-sample of the original study. Analyses were carried out using dilutions of serum samples from fitted values corresponding to optical densities from antibody detection assays. These were obtained from the ligand binding equation and mid point titres in dose-response curves were then calculated. Vitamin A supplementation had no effect on the midpoint titres of Hepatitis B and H. influenzae type b vaccine derived antibodies. The significant effect of vitamin A supplementation on the Hepatitis B vaccine component observed in a previous seroprotection analysis is probably due to the amount of antibodies since affinity was unaffected.
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PMID:Seroprotection associated with infant vitamin A supplementation given with vaccines is not related to antibody affinity to Hepatitis B and Haemophilus influenzae type b vaccines. 2048 61