Ignite Creation Date:
2025-12-17 @ 4:20 PM
Ignite Modification Date:
2025-12-24 @ 12:41 AM
Study NCT ID:
NCT00792051
Status:
COMPLETED
Last Update Posted:
2014-12-30
First Post:
2008-11-13
Is Possible Gene Therapy:
False
Has Adverse Events:
False
Brief Title:
Direct and Indirect Benefits of Influenza Vaccine Versus Placebo in Healthy Children
Sponsor:
The University of Hong Kong
Organization:
Study Overview
Official Title:
A Randomised Controlled Trial of the Effectiveness of Vaccinating Children to Reduce Household Transmission of Influenza
Status:
COMPLETED
Status Verified Date:
2014-12
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
While immunisation of school-age children against influenza is not recommended in Hong Kong, past experience in Japan and elsewhere suggests that immunisation of children may protect the wider community through its indirect transmission-limiting impact as well as the direct immunologic protection afforded vaccinated children themselves. We aim to assess whether vaccinating children against influenza protects vaccinees as well as their household contacts from infection.
Detailed Description:
Design and subjects: A double-blind randomised controlled trial of 800 subjects aged 6-17 drawn from the general population and their 2000 household contacts. The subjects will be randomised in a 3:2 ratio to the intervention and placebo groups, respectively. Serum samples will be collected from subjects pre- and 1 month post-vaccination, and after the influenza season. Serum samples will be collected from household contacts at baseline and at the end of the influenza season. During the follow-up period, subjects and household members will keep symptom diaries and those reporting influenza-like-illness will be offered free doctor consultations or home visits where we will arrange for collection of nose and throat swabs.
Study instruments: An antibody titre of ≥40 in the post-vaccine serum will be used to define seroprotection to those particular strains, while a four-fold or higher increase in antibody titres between baseline and end-of-season follow-up of the household contacts will define influenza infection during the season. Subjects and household contacts will be asked to keep symptom diaries, and during episodes of ILI we will collect nose and throat swabs for laboratory confirmation of influenza infection; the primary serology results will then be compared with clinical and laboratory-confirmed influenza episodes.
Interventions: 1 (intervention) inactivated influenza vaccine (Vaxigrip, Sanofi Pasteur); 2 (placebo) saline injection.
Main outcome measures: The proportions of subjects and household contacts with serology-confirmed influenza infection during follow-up among the 2 intervention arms.
Analysis: Intention to treat, adjusting for within-household correlation in influenza attack rates.
Study instruments: An antibody titre of ≥40 in the post-vaccine serum will be used to define seroprotection to those particular strains, while a four-fold or higher increase in antibody titres between baseline and end-of-season follow-up of the household contacts will define influenza infection during the season. Subjects and household contacts will be asked to keep symptom diaries, and during episodes of ILI we will collect nose and throat swabs for laboratory confirmation of influenza infection; the primary serology results will then be compared with clinical and laboratory-confirmed influenza episodes.
Interventions: 1 (intervention) inactivated influenza vaccine (Vaxigrip, Sanofi Pasteur); 2 (placebo) saline injection.
Main outcome measures: The proportions of subjects and household contacts with serology-confirmed influenza infection during follow-up among the 2 intervention arms.
Analysis: Intention to treat, adjusting for within-household correlation in influenza attack rates.
Study Oversight
Has Oversight DMC:
True
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?: