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

The study employs a community-based interventional design with a control group. A total of 1,200 elderly participants (600 per group) will be recruited using multi-stage sampling. The intervention group receives a multi-component communication package: * Training for local health workers and collaborators. * Direct community communication sessions using leaflets. * Social media updates and monthly household visits. The control group receives standard health information. Effectiveness is measured by comparing pre- and post-intervention vaccination rates using the Difference-in-Differences (DID) analytical method.