Natural History of Systemic and Nasal Mucosal Immunity After Influenza Vaccination in a Pediatric Population
Condition: Influenza Immunity
MeSH terms: Influenza, Human
Study type: Observational

Summary: 
      Background:

      The influenza (flu) virus infects millions around the world every year. Children are at
      increased risk of complications from the flu. The flu vaccine protects against influenza, but
      the vaccine can be improved. Researchers want to learn more about children s mucosal and
      systemic immunity after flu vaccination. This could help to develop more effective flu
      vaccines in the future.

      Objective:

      To learn what happens in kids immune systems after receiving a flu vaccine.

      Eligibility:

      Children ages 2-17 who have received a flu vaccine in the past and plan to get the current
      seasonal flu vaccine given by injection.

      Design:

      All study visits will take place at home and communication with the study team will be done
      via phone or videoconference.

      Participants will review medical history and flu vaccination history with the study team.

      Participants will get the flu vaccine at their local doctor s office or pharmacy. They will
      not be given the vaccine in this study.

      Participants will complete an electronic survey to give details about the date and type of
      flu vaccine received.

      Participants will collect nasal and fingerstick samples at home. They will collect 4 nasal
      samples and 3 fingerstick samples over 6 months: once before they get the flu vaccine and 2-3
      times after they get the vaccine. They will use collection kits that include instructions,
      sample collection supplies, and shipping materials. They will ship all samples back to NIH
      with all costs covered by NIH.

      Participation will last for 6 months.

      Compensation is provided.
    

Detailed description: 
      Title:

      Natural History of Systemic and Nasal Mucosal Immunity after Influenza Vaccination in a
      Pediatric Population

      Study Description:

      While adults are heavily represented in influenza vaccine studies, there are limited studies
      in the pediatric population. This study will characterize the changes in nasal and systemic
      immunity after influenza vaccination in a pediatric population.

      Objectives:

      Primary Objectives:

      Characterize nasal mucosal humoral immune response pre and post influenza vaccination

      Characterize systemic humoral immune response pre and post influenza vaccination

      Secondary Objectives:

      Describe the trend of nasal mucosal mucosal and serum humoral immune response over time after
      vaccination

      Endpoints:

      Primary Endpoints:

        1. Baseline and post-vaccination mucosal anti-influenza antibodies from nasal samples as
           measured by:

             1. Anti-hemagglutination (HA) head antibody quantitative enzyme-linked immunosorbent
                assay (ELISA) immunoglobulins (Ig) (IgA, IgG)

             2. Anti-HA stalk antibody quantitative ELISA (IgA, IgG)

             3. Anti-neuraminidase (NA) antibody quantitative ELISA (IgA, IgG)

        2. Baseline and post-vaccination systemic anti-influenza antibodies as measured by:

             1. Anti-HA head antibody quantitative ELISA (IgM, IgG, IgA)

             2. Anti-HA stalk antibody quantitative ELISA (IgM, IgG, IgA)

             3. Anti-NA antibody quantitative ELISA (IgM, IgG, IgA)

      Secondary Endpoints:

      Multiple timepoint measurements of mucosal anti-influenza antibodies from nasal samples as
      measured by:

      Anti-HA head antibody quantitative ELISA (IgA, IgG)

      Anti-HA stalk antibody quantitative ELISA (IgA, IgG)

      Anti-NA antibody quantitative ELISA (IgA, IgG)

      Multiple timepoint measurements of systemic anti-influenza antibodies as measured by:

      Anti-HA head antibody quantitative ELISA (IgM, IgG, IgA)

      Anti-HA stalk antibody quantitative ELISA (IgM, IgG, IgA)

      Anti-NA antibody quantitative ELISA (IgM, IgG, IgA)

      Study Population:

      Children who are >= 2 years and < 18 years of age (N = 51; accrual ceiling = 100).
      Participants will be enrolled by age group: 2 - 6 years old, 7 - 11 years old and 12 - 17
      years old with a goal enrollment of 17 per group.

      Description of Sites/Facilities Enrolling Participants:

      Participants will be enrolled by telephone or videoconference, and sample collections will be
      done in participant homes. Recruitment will be from community pediatric clinics and self- or
      family referral.

      Study Duration:

      2 years
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Children receiving their first ever influenza vaccine require two doses of the vaccine one
        month apart and will not be included in this study. Only participants who have already
        received a flu vaccine series in the past will be eligible for this study. Evaluation of
        immunity after the first ever influenza vaccination series is an important question that
        should be explored separately. We will enroll participants into one of three cohorts by
        age: 2 6 years old, 7 11 years old, and 12 17 years old. We will aim to enroll similar
        numbers of participants into each group to ensure a diverse age range in our population.
      
Keywords: Flu; Flu Shot; Children; Natural History