Communication Intervention to Improve Influenza Vaccination Rates Among Elderly in Can Tho

NCT07508189 | Active Not Recruiting

• 1 other identifier: NIHE IRB - 40/2025
• Study Type: interventional
• Target: 1,200
• Locations: 1 country
• Sites: 1

Brief Summary

This study evaluates the effectiveness of a multi-component community-based communication intervention to increase influenza vaccination rates among adults aged above 65 years in Can Tho City, Vietnam. Using a cluster randomised controlled trial design with stratified lottery randomisation, four study sites were selected from eight sites surveyed in a prior study: O Mon Ward and Truong Thanh Commune (intervention); Phuoc Thoi Ward and Truong Xuan Commune (control). The intervention includes community health education sessions, healthcare worker training, household visits, health communication banners, and Zalo-based vaccination reminders, delivered over 12 months (September 2025 to September 2026). Effectiveness is assessed by comparing pre- and post-intervention outcomes using Difference-in-Differences (DID) analysis.

Conditions

Influenza; Vaccination Coverage; Health Communication

Keywords

Influenza Vaccines; Elderly; Health Communication; Vaccination Coverage; Community-based Intervention; Vietnam

Outcome Measures

Primary Outcomes (1)

• Influenza vaccination uptake in the preceding 12 months

  Proportion of participants who received influenza vaccination in the 12 months prior to survey, assessed by self-report. Baseline assessed August 2025; follow-up assessed September 2026. Intervention effect estimated using Difference-in- Differences (DID) regression comparing change between intervention and control clusters.

  Up to 12 months

Secondary Outcomes (6)

• Influenza vaccination in calendar year 2025

  Up to 12 months

• Influenza vaccination intention

  Baseline and up to 12 months

• Healthcare worker vaccination counselling

  Baseline and up to 12 months

• Influenza knowledge score

  Baseline and up to 12 months

• Vaccine hesitancy score (WHO-SAGE Vaccine Hesitancy Scale)

  Baseline and up to 12 months

Study Arms (2)

Multi-component Health Communication

EXPERIMENTAL

Adults aged \>65 years in 2 intervention clusters (O Mon Ward and Truong Thanh Commune) receive a multi-component package: Phase 1 (Sep 2025): (1) Two community health education sessions/ site for older adults and one family member, with influenza leaflets. (2) One HCW capacity-building workshop/site (O Mon: n=30; Truong Thanh: n=20). (3) Thirty household visits/site by community health volunteers. Phase 2 (Sep 2025-Sep 2026): (4) Health communication banners at health stations and community centres. (5) HCW point-of-care vaccination counselling at all clinical contacts. (6) Zalo-based weekly reminders and educational content (Dec 2025-Jan 2026).

Behavioral: Multi-component Health Communication Package

Routine Immunization Information

NO INTERVENTION

Participants in this arm receive standard care and routine immunization information provided by the local health station without the additional communication package.

Interventions

Multi-component Health Communication Package BEHAVIORAL

A 12-month cluster-level communication intervention (Sep 2025-Sep 2026) delivered in two phases to all adults aged \>65 years in intervention clusters: Phase 1 (Sep 2025): (1) Two community health education sessions/site with influenza leaflets for older adults and family members; (2) HCW capacity-building workshop/site (O Mon: n=30; Truong Thanh: n=20); (3) Thirty household visits/site by community health volunteers. Phase 2 (ongoing): (4) Health communication banners at health stations and community centres; (5) HCW point-of-care vaccination counselling at all clinical contacts; (6) Zalo-based weekly educational content and vaccination reminders (Dec 2025-Jan 2026).

Multi-component Health Communication

Eligibility Criteria

• Age: 66 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Older Adult (65+)

You may qualify if:

• Residents living in selected wards/communes in Can Tho City for at least 6 months.
• Aged above 65 years.
• Mentally and physically capable of participating in interviews and receiving communication interventions.
• Agree to participate in the study and provide informed consent.

You may not qualify if:

• Individuals with severe cognitive impairment or dementia.
• Individuals with contraindications to influenza vaccination.
• Planning to move out of the study area during the 12-month follow-up period.

Sponsors & Collaborators

• Can Tho University of Medicine and Pharmacy: lead
• National Institute of Hygiene and Epidemiology, Vietnam: collaborator

Study Sites (1)

Can Tho University of Medicine and Pharmacy

Can Tho, Can Tho City, 900000, Vietnam

Location

MeSH Terms

Conditions

Influenza, Human

Condition Hierarchy (Ancestors)

Respiratory Tract Infections; Infections; Orthomyxoviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Masking Details: Due to the nature of the community-based health communication intervention, masking of participants and investigators is not feasible.
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: A cluster randomized controlled trial where wards/communes are the unit of randomization. Participants in intervention clusters receive multi-component communication, while control clusters receive standard care.

Study Record Dates

• First Submitted: March 27, 2026
• First Posted: April 2, 2026
• Study Start: September 1, 2025
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: July 6, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

VN (1)