Immunisation status against major diseases preventable with vaccines in multiple sclerosis patients

Abstract Background Multiple sclerosis (MS) patients are more susceptible to infections than the general population due to the utilization of immunosuppressive drugs (DMDs) which require particular attention to the occurrence of infectious events. So, immunisation policies are mandatory or recommended. Methods In this pilot study, subjects receiving a diagnosis of relapsing-remitting MS since 2011 at a MS center in central Italy were enrolled. The immunization status against major infectious agents and safety of most used vaccines were recorded. Results 103 patients (67% females), mean age 42 years, with no or mild disability (85%) were examined. The majority received vaccines against poliomyelitis (92%), hepatitis B (47%), tetanus and diphtheria (89%), but a small percentage got boosters every 10 years (31% for tetanus and 28% for diphtheria); other vaccines evaluated: pertussis (37%), mumps (23%), meningococcus B, C (5%), flu (1%). Evaluating immunization status due to vaccines or illnesses, a significant percentage of patients using immunosuppressive drugs was susceptible to infections, such as measles (44%), chicken pox (32%) and rubella (65%). Only 17% of patients were vaccinated after diagnosis and, regarding vaccine safety, only 1 had a relapse within 6 months following measles, mumps and rubella vaccine. Conclusions This study shows a very low number of vaccinations among patients, confirming the need of preventive information on their importance and safety for MS patients: major adverse events of therapy in MS include severe infections and the majority of patients are female in reproductive age. This pilot phase was followed by an ongoing study involving 25 Italian MS Centers and 3000 patients that will provide in 2022 useful results on vaccination policies and safety. The knowledge of immunisation status is crucial for the clinical practice in the management of DMDs, and for the public health policies for a vaccine campaign targeted to MS patients. Key messages Lack of information on vaccine safety bring to a low adherence to immunization program. The immunization status of patients is essential for a correct management of therapies.