Vaccination coverage against Influenza remains low especially among vulnerable populations. The rate of vaccination and the associated factors in pwMS  remain unknown. Identifying the factors associated with  vaccination is important for clinical practice and healthcare policies.

To evaluate influenza vaccination coverage and its predictors among patients with multiple sclerosis (pwMS)  in the UK.

This observational study included adult patients from Barts Health NHS Trust, London, UK with definite diagnosis of MS,  who were invited to complete an online survey about influenza vaccination between 2018-2019. Logistic regression analyses were performed to obtain predictors of influenza vaccination. 

Two hundred and five (205)  participants  (median age 46,IQR] 38-55, 70% female) completed the online survey, of whom 78% reported being vaccinated for that year. Previous vaccination was the only independent predictor for future vaccination (OR 1.39, 95% CI 1.28-1.51, p<0.001 ). Predictors of no vaccination were receiving no information about the vaccine (OR 0.84 95% CI 0.76-0.92),  fear of vaccination (OR 0.81, 95% CI 0.68-0.98) or MS related side effects (OR 0.65  95% CI 0.55-0.77),  being an anti-vaccine advocate (OR 0.6 95% CI 0.48-0.75), having had a past negative experiences with vaccination (OR 0.56 95% CI 0.47-0.66), having concerns on interaction with disease modifying therapies (OR 0.53 95% CI 0.39-0.73), or other non medical issues (OR 0.49 95% CI 0.42-0.57).

PwMS that have been previously vaccinated against influenza are 50% more likely to opt for future vaccination. Receiving no direct information about the vaccine, having fears of side effects or interactions, or having previous negative experiences are independent negative factors against vaccination. These are modifiable factors that could be addressed to increase vaccination rates in this population.