Streptococcus pneumoniae, commonly called pneumococcus, can cause a wide range of diseases in children from mild ear infections to deadly pneumonia or meningitis. Vaccination is currently the single best way to protect children. Nutrition, especially the amount of vitamin A, may play a role in how well your body responds to infection or a vaccine. We call this an immune response. This research will look to see if children who take a vitamin with their vaccine have a better immune response than children who do not take a vitamin with their vaccine. Primary Objective To evaluate the influence of vitamin A supplementation on Prevnar vaccine immunogenicity based on changes in antibody scores in a commercial ELISA at Day 21 (after a booster vaccine dose) compared to pre-vaccine values. Secondary Objectives * To evaluate the relationship between baseline vitamin levels and pneumococcal or hepatitis A vaccine antibody responses (based on in commercial ELISAs) at Days 0 and 21. * To evaluate the influence of vitamin A supplementation on hepatitis vaccine immunogenicity based on changes in antibody scores in a commercial ELISA at Day 21 compared to pre-vaccine values. * To evaluate relationships between total serum antibodies (based on individual IgM, IgG1, IgG2, IgG3, IgG4, and IgA scores in a Luminex assay) at Day 0 and changes between Days 0 and 21 with baseline (Day 0) vitamin levels in young children, and with vitamin A supplementation.
Children between the ages of 1 and 4 years old (inclusive) will be enrolled. All will receive PCV and hepatitis A vaccination. Those randomized to the treatment arm will receive 10,000 IU orally at the time of vaccination, while those randomized to the control arm will only receive vaccines. Vitamin levels and antibody responses towards the vaccines will be measured at screening, Day 0 (vaccination day) and Day +21. Children will be randomized using a stratified permuted block method.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
NONE
Enrollment
22
liquid oral vitamin A supplementation
No vitamin A supplementation
St. Jude Children's Research Hospital
Memphis, Tennessee, United States
Seroconversion rate in two arms
The seroconversion rate, defined as the proportion of 4X increases or conversion from undetectable to detectable response in vaccine-specific antibody after vaccinations (Day 21) versus the baseline (Day 0) antibody level in intervention and control groups will be estimated and 95% confidence interval will be described for both groups. The 95% confidence interval will serve as a measure of precision of the seroconversion rate estimate. Chi-square test will be performed to make the comparison between two arms.
Time frame: Measured at Day 21
Sera titer ratio
Titer ratios will be summarized with descriptive statistics. Two-sample tests (t-test or Wilcoxon rank-sum test) will be applied whenever appropriate
Time frame: Measured at Day 21
Spearman's correlation coefficient of vaccine antibody responses at days 0 with baseline vitamin levels for each arm.
Spearman's correlation coefficient.
Time frame: Measured at Day 21
Spearman's correlation coefficient of vaccine antibody responses at days 21 with baseline vitamin levels for each arm.
Spearman's correlation coefficient.
Time frame: Measured at Day 21
Proportion of subjects showing 4X increases or conversion from undetectable to detectable response in B cell responses after vaccinations for both groups, and by VA/VD stratum.
The proportion difference with 95% confidence interval will be reported via Chi-square test or Fisher's test.
Time frame: Measured at Day 21
Correlation of immunoglobulin M (IgM) antibody (measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin G subclass 1 (IgG1) antibody (measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin G subclass 2 (IgG2) antibody (measured by Luminex assay
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin G subclass 3 (IgG3) antibody(measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin G subclass 4 (IgG4)antibody(measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin A (IgA) antibody(measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient
Time frame: Measured at Day 21
Correlation of immunoglobulin M (IgM) antibody(measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin G subclass 2 (IgG2) antibody(measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin G subclass 3 (IgG3) antibody (measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin G subclass 4 (IgG4) antibody(measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
Correlation of immunoglobulin A (IgA) antibody(measured by Luminex assay)
Correlation will be expressed as Spearman's correlation coefficient.
Time frame: Measured at Day 21
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