Intrinsic motivation drives influenza vaccination uptake among Greek primary healthcare workers

Background

Influenza vaccination among healthcare workers remains suboptimal across Europe, despite their critical role in shaping public vaccination behavior. Understanding determinants of uptake is essential for designing effective public health interventions.

Methods

A cross-sectional study was conducted among 304 primary healthcare workers (physicians and pharmacists) in Greece using a structured online questionnaire. Vaccination uptake (2023–2024 season and annual) were assessed alongside motivation and advocacy constructs using validated MoVac-flu and MovAd scales. Factor structure was evaluated through confirmatory and exploratory factor analyses, and multivariable logistic regression identified independent predictors of vaccination uptake.

Results

Influenza vaccination uptake reached 77.6% (seasonal) and 75.3% (annual). Motivation and advocacy scores were high overall, with vaccinated participants demonstrating significantly higher levels across all subscales (p < 0.05). A refined multidimensional structure of vaccination attitudes was identified, with strong internal consistency (Cronbach’s α > 0.87). Intrinsic motivation, particularly the “Vax Self-Care” dimension, emerged as the strongest predictor of vaccination uptake (aOR=3.66, 95% CI: 2.33–5.77 for seasonal vaccination; aOR=3.22, 95% CI: 2.08–4.96 for annual vaccination). Communication-related competencies were also independently associated with annual vaccination (aOR=1.64, p = 0.007). Living with vulnerable individuals influenced seasonal uptake (aOR=2.95, p = 0.020), while male sex was associated with higher annual vaccination (aOR=2.35, p = 0.020).

Conclusions

Intrinsic motivational factors are key drivers of influenza vaccination among healthcare workers, outweighing contextual influences. Public health strategies should prioritize strengthening internalized beliefs, perceived value of vaccination, and communication skills to achieve sustained improvements in vaccine uptake and advocacy.

Key messages

• Intrinsic motivation is the strongest determinant of vaccination uptake.

• Targeted behavioral interventions can enhance both uptake and advocacy.