Revolutionizing Influenza Vaccination in Children: A New Approach

BACKGROUND: Influenza vaccine is not included in the Hong Kong Government's universal Childhood Immunisation Programme but eligible children can receive subsidised vaccine through the private sector using the Vaccination Subsidy Scheme (VSS). This study examined whether a simple intervention package can increase influenza vaccine uptake in Hong Kong children.

METHODS: Two study samples were enrolled: families of children who had participated in a previous knowledge, attitudes and practices study; and mother-infant pairs recruited from postnatal wards. Control groups received publicly available leaflets about VSS. Intervention groups additionally received: (1) a concise information sheet about influenza and its vaccine; (2) semi-completed forms to utilise the subsidy; (3) contacts of VSS clinics that did not charge above the subsidy; and (4) text message reminders for vaccination. Enrolled mothers were contacted when children were approximately 1 and 2 years old to determine influenza vaccination status of the families and their plan to vaccinate their children. Mothers' attitudes towards influenza vaccine were assessed at enrolment and at the end of the study.

RESULTS: A total of 833 eligible mother-infant pairs were enrolled from the two samples. The intervention package improved influenza vaccine uptake by 22% at one year and 25% at two years of age. Maternal influenza vaccine uptake in intervention group was higher during this two-year period in those who had never been previously vaccinated. Mothers' self-efficacy regarding the use of influenza vaccine in her child i.e. belief and confidence in her own ability to make a good decision, was also improved with the intervention.

CONCLUSIONS: A four-component intervention package could improve influenza vaccine uptake in Hong Kong children and their mothers during the first two years of life and depending on vaccine effectiveness could potentially reduce influenza-associated hospital admissions in children below 2 years old by 13-24%.

The Source Article References

• Assessing disease burden of respiratory disorders in Hong Kong children with hospital discharge data and linked laboratory data by Nelson, 2007 in Hong Kong Med J
• Burden of influenza infection in hospitalised children below 6 months of age and above in Hong Kong from 2005 to 2011 by Nelson, 2014 in Vaccine
• Hospitalization incidence, mortality, and seasonality of common respiratory viruses over a period of 15 years in a developed subtropical city by Chan, 2015 in Medicine (Baltimore)
• The effectiveness of influenza vaccination in preventing hospitalizations in children in Hong Kong, 2009–2013 by Cowling, 2014 in Vaccine
• Influenza vaccine effectiveness in hospitalised Hong Kong children: Feasibility of estimates from routine surveillance data by Yeung, 2018 in Vaccine
• Seasonal influenza vaccination coverage survey for the 2012/13 season by Chan, 2013 in Commun Dis Watch
• World Immunization Week 2013 by Wong, 2013 in Commun Dis Watch
• Coverage and parental perceptions of influenza vaccination among parents of children aged 6 to 23 months in Hong Kong by Lau, 2013 in BMC Public Health
• Effect of patient reminder/recall interventions on immunization rates: a review by Szilagyi, 2000 in JAMA
• Seasonal influenza vaccination reminders for children with high-risk conditions: a registry-based randomized trial by Dombkowski, 2012 in Am J Prev Med
• Implementation of universal influenza immunization recommendations for healthy young children: results of a randomized, controlled trial with registry-based recall by Kempe, 2005 in Pediatrics
• How to randomise by Altman, 1999 in BMJ
• The health belief model: a decade later by Janz, 1984 in Health Educ Q
• Social learning theory and the Health Belief Model by Rosenstock, 1988 in Health Educ Q
• Using the Health Belief Model to understand caregiver factors influencing childhood influenza vaccinations by Chen, 2011 in J Community Health Nurs
• Misperceptions about influenza vaccination among parents of healthy young children by Daley, 2007 in Clin Pediatr (Phila)
• Do parents understand immunizations? A national telephone survey by Gellin, 2000 in Pediatrics
• Maternal knowledge, attitudes and beliefs regarding gastroenteritis and rotavirus vaccine before implementing vaccination program: which key messages in light of a new immunization program? by Morin, 2012 in Vaccine
• Immunization status and sociodemographic characteristics: the mediating role of beliefs, attitudes, and perceived control by Prislin, 1998 in Am J Public Health
• Parental delay or refusal of vaccine doses, childhood vaccination coverage at 24 months of age, and the Health Belief Model by Smith, 2011 in Public Health Rep