As always you need to document it and contact your MS centre. I suggest doing this remotely using telephone, email, WhatsApp or via SMS messaging. You want to avoid attending the MS centre unless you have to. Obviously the former advice needs to be applied on a case-by-case basis; if the relapse is disabling and severe you may need to be assessed in clinic or even admitted for treatment and management.
Again there is no reason why relapse assessments can't be done using telemedicine. MS clinical nurse specialists having been doing telephone assessments for decades. It is even possible for your neurologist to do some of the neurological examination by asking you to do things and observing them via a video-link, for example walking heel-to-toe, hopping on either leg unsupported and observing your eye movements. Although a video neurological examination is not ideal it at least allows a cursory neurological assessment to be performed. You can also go online and complete the web-EDSS calculator and other outcome measures, for example the 9-hole-peg test and the timed-25-foot-walk, to provide your MS team with your current level of disability.
When it comes to treating relapses during the COVID-19 pandemic it is advisable to try and not use steroids. Steroids actually make little difference to the final outcome of relapses, but simply speed up the recovery from the relapse. The downside of steroids, even pulsed high-dose oral steroids, is that they are immunosuppressive and at least theoretically increase your chances of getting symptomatic and severe COVID-19 viral infection.
Date & Disclaimer: 18-March-2020; please note this information will be time limited and will change as new data emerges.