Influenza Vaccination Coverage among Multiple Sclerosis Patients: Evolution over Time and Associated Factors

Vaccination coverage and its determinants in patients with multiple sclerosis-a multicenter cross-sectional study

Background

Complete vaccination coverage is recommended by multiple sclerosis (MS) societies for patients with multiple sclerosis (pwMS) to mitigate infection risks associated with disease-modifying therapies (DMTs).

Objectives

To analyze vaccination coverage and its determinants in pwMS compared to healthy controls, considering vaccination hesitancy, MS-specific vaccination beliefs, trust in information sources, and the role of general practitioners (GPs).

Methods

This cross-sectional multicenter observational study was conducted in six German MS centers. The primary endpoint was a vaccination index (VI) comprising eight standard vaccinations (range 0-1, with higher VI indicating better vaccination coverage). Secondary endpoints included validated measures of general vaccination hesitancy, MS-specific vaccination beliefs, and trust in information sources. Data were collected through questionnaires, vaccination card analysis, and a survey of GPs who vaccinate pwMS.

Results

VI tended to be lower in pwMS (n = 397) compared to healthy controls (n = 300; 0.58 ± 0.30 vs 0.62 ± 0.31, p = 0.057). In pwMS receiving highly effective DMTs, VI did not differ significantly from those on no/platform DMTs. Vaccination hesitancy was comparably low, with no differences between pwMS and controls. Vaccination hesitancy, beliefs, and trust in information sources explained only 10%-16% of the variance in VI. Among 109 GPs, 82% cited reluctance to vaccinate pwMS due to concerns about MS-related side effects or interactions with DMTs.

Conclusion

Despite clear recommendations from MS societies for full vaccination of all pwMS, vaccination coverage remains worryingly low. Approximately half of the patients lack standard vaccination coverage, even those on highly effective DMTs. In fact, vaccination coverage in pwMS tended to be even lower than in healthy controls. Vaccination hesitancy and other intrinsic factors do not sufficiently explain the low vaccination rates. Inconsistent vaccination recommendations from GPs due to uncertainties about vaccine safety and DMT interactions likely contribute.

Immunogenicity of a seasonal influenza and a pneumococcal polysaccharide vaccine in multiple sclerosis patients under disease modifying therapies: A single-center prospective study

BACKGROUND

Immunogenicity of influenza and pneumococcal vaccines varies and requires further elucidation in patients with multiple sclerosis (MS) under treatment with disease-modifying therapies (DMTs).

METHODS

Adult MS patients who consented with vaccination after standard-of-care consultation by their treating physicians were enrolled. All received a single dose of an inactivated quadrivalent influenza vaccine and of the 23-valent pneumococcal vaccine. A blood sample was collected before and after four weeks of vaccination for measurement of antibodies against Influenza A, B and S. pneumoniae. Patients were followed-up for adverse events and MS relapse for 12 months.

RESULTS

One hundred and seventy-two patients (65.7 % female, mean age 42 ± 13 years old, mean MS duration 7.6 ± 7.2 years, 81.4 % under DMTs) were enrolled from November 2019 to March 2020. Antibody measurements were available for 151 patients. Seropositivity for anti-PPSV23 did not differ between baseline and at 4 weeks of follow-up (n = 56, 37.1 %). There was a significant increase of absolute antibody titers post-vaccination for both influenza A and B (p < 0.001). For Influenza A, seropositivity was evident for 57 (37.7 %) patients at 4 weeks compared to 19 (12.6 %) patients at baseline (pMcNemar < 0.001). For Influenza Β, 110 (72.8 %) seroconverted 4 weeks after vaccination compared to 12 (7.9 %) at baseline (pMcNemar < 0.001). Interferon and fumarate did not affect influenza seroconversion while rituximab was associated with lower titers. Mild local AEs (pain, edema) were observed in 23.8 %; no severe AE was reported. Thirty-four patients (19.8 %) had a relapse during the 12-month follow-up; none was attributed to the vaccination.

CONCLUSIONS

Seroconversion in MS patients on treatment was more frequent following influenza compared to PPSV23 vaccination. Rituximab had an effect on the height of the immune response. Better immunization coverage as well as future evaluation of the breadth of immune response elicited by immunization is necessary for these patients.

COVID-19 Vaccination Coverage and Associated Factors in Patients with Multiple Sclerosis

Our objective was to know the COVID-19 vaccination coverage in multiple sclerosis (MS) patients and its factors associated. A retrospective cohort study was carried out. Patients seen at the MS unit of the University Clinical Hospital of Zaragoza between 2017 and 2021 were included. Variables were obtained by reviewing the specialized and primary care records. Associations between receiving COVID-19 full primo-vaccination, as well as one booster dose since autumn 2022, and the other variables were analyzed using bivariate analysis and multiple logistic regression models. Of the 359 included patients, 90.3% received the COVID-19 full primo-vaccination. Having been born in Spain (aOR = 3.40) and having received the 2020-2021 influenza vaccine (aOR = 6.77) were associated with receiving the COVID-19 full primo-vaccination. Vaccination with a COVID-19 booster dose was detected in 141 patients (39.3%). Sex (man) (aOR = 2.36), age (60 years or over) (aOR = 6.82), type of MS (Primary Progressive/Secondary Progressive) (aOR = 3.94), and having received the 2022-2023 influenza vaccine (aOR = 27.54) were associated with receiving such a booster dose. The COVID-19 booster dose was administered at the same time as the 2022-2023 influenza vaccine in 57.8% (67/116) of the patients vaccinated with both vaccines. The COVID-19 full primo-vaccination coverage is higher than in other countries. However, the decrease in vaccination coverage with the booster dose makes it necessary to develop strategies to improve it that are not limited to administering the flu vaccine together with the COVID-19 booster dose. Such strategies should be in focus, especially for women under 60 years of age.

Influenza Vaccination among Multiple Sclerosis Patients during the COVID-19 Pandemic

In the context of the COVID-19 pandemic, the co-circulation of influenza and SARS-CoV-2 viruses may have severe complications for vulnerable populations. For this reason, the World Health Organization pointed to the 2020-2021 anti-influenza campaign as being of special relevance. Our aim was to assess the 2020-2021 influenza vaccination coverage, and its associated factors, among patients in a Spanish multiple sclerosis (MS) unit. A cross-sectional study was conducted. People attending the MS unit of the Clinical Hospital of Zaragoza during 2020 were included. Variables were obtained by reviewing records. Associations with 2020-2021 influenza vaccination were analyzed using bivariate analysis and a multiple logistic regression model. A total of 302 patients were studied; 62.6% were women, whose mean age (standard deviation) was 47.3 (11.5) years. The 2020-2021 influenza vaccination coverage was 55.3% (59.8% in women and 47.8% in men). A total of 89.7% had at least one other indication for vaccination (e.g., immunosuppressive treatment in 225 patients). The variables associated with getting vaccinated were being female (adjusted odds ratio (95% confidence interval) (aOR (95%CI) = 2.12 (1.12-3.99)), having received the 2019-2020 influenza vaccine (aOR (95%CI) = 31.82 (14.71-68.86)) and being born in Spain (aOR (95%CI) = 12.91 (1.07-156.28)). Coverage is moderate compared to other countries. It is necessary to develop strategies to improve it, especially in men and those born outside Spain.