ALL vaccines can be given to MS patients, EXCEPT those containing live attenuated viruses, as the latter can trigger attacks and are contraindicated in the case of many MS treatments. One instance is the yellow-fever vaccine. Childhood diseases do not predispose to MS in adult life (measles, rubella, chickenpox, mumps, etc.). Children must be vaccinated against these diseases and receive the necessary booster shots (including tetanus and diphtheria). Natural flu can trigger an MS attack and high fevers aggravate the symptoms of MS. MS patients who have a great deal of contact with other people and are aged 50-55 should have themselves vaccinated against flu. The precautions taken for protection against COVID-19 are also effective against the influenza virus! The idea that a second dose of flu vaccine should be given to patients being treated with Ocrevus®, Tysabri®, Mavenclad® or Gilenya® remains a theory and is not applicable at this point in time. An antibody titer needs to be made further to the first vaccination to check whether it is high enough. In any case, vaccines are never 100% effective.