B cells oh B cells you’re great at telling the T cells to attack bad things but leave me alone. Not doing medical words (cause remembering them is an issue) I look at the flu and COVID jabs v Ocrevus as this. In your immune system live B Cells and T Cells. The B cells telling the T cells what to attack. With the flu vaccine your body sees that as a tweak, carries out that tweak and moves on. With the COVID vaccine your body says “Sir, yes Sir.”and does as it’s told, getting the B cells to tell the T cells to attack COVID. Now with MS the B cells also get the T cells to attack you (damn you B cells). Ocrevus (other DMDs are available, but as it’s the one I get, I will look at that) works by telling the B cells not to attack you, but for a limited time. B cells come in 3 basic forms: Young, Mature and Old. To get them not to attack you, Ocrevus says “You old guys won’t listen to me and you mature dudes might and might not but you youngsters are still impressionable” so along with temporarily altering the B cell generator it kills off the Old and Mature B cells while leaning on the impressionable youngsters, hence the term “Immunosuppressed”. Lets now introduce an Ocrevus infused body and a COVID vaccine to each other. Whilst there are fewer of them, the B cells still say “Sir, yes Sir”. So after infusion we wait until that limited time is over and there are loads of B cells before we have a COVID jab and even then we should not get that jab and the flu jab at the same time, as whilst our B cells are attacking us, keeping nasties at bay and tweaking the system to also ask them to say “Sir, yes Sir” is too much as like men folk (so I am told) multi tasking is not a strong point. In short ask “how does this vaccine works in people with MS?” not just “how does it work?”