Editing Multiple sclerosis (section)

===Relapses===
Relapses are usually unpredictable, occurring without warning.<ref name="pmid1897097722"/> Exacerbations rarely occur more frequently than twice per year.<ref name="pmid1897097722"/> Some relapses, however, are preceded by common triggers and they occur more frequently during spring and summer.<ref name="pmid168043312">{{cite journal | vauthors = Tataru N, Vidal C, Decavel P, Berger E, Rumbach L | title = Limited impact of the summer heat wave in France (2003) on hospital admissions and relapses for multiple sclerosis | journal = Neuroepidemiology | volume = 27 | issue = 1 | pages = 28–32 | year = 2006 | pmid = 16804331 | doi = 10.1159/000094233 | s2cid = 20870484 }}</ref> Similarly, viral infections such as the [[common cold]], [[influenza]], or [[gastroenteritis]] increase their risk.<ref name="pmid1897097722"/> [[Stress (medicine)|Stress]] may also trigger an attack.<ref name="pmid17439878">{{cite journal | vauthors = Heesen C, Mohr DC, Huitinga I, Bergh FT, Gaab J, Otte C, Gold SM | title = Stress regulation in multiple sclerosis: current issues and concepts | journal = Multiple Sclerosis | volume = 13 | issue = 2 | pages = 143–148 | date = March 2007 | pmid = 17439878 | doi = 10.1177/1352458506070772 | s2cid = 8262595 }}</ref>

Many events do not affect rates of relapse requiring hospitalization including [[vaccination]],<ref>{{cite journal | vauthors = Confavreux C, Suissa S, Saddier P, Bourdès V, Vukusic S | title = Vaccinations and the risk of relapse in multiple sclerosis. Vaccines in Multiple Sclerosis Study Group | journal = The New England Journal of Medicine | volume = 344 | issue = 5 | pages = 319–326 | date = February 2001 | pmid = 11172162 | doi = 10.1056/NEJM200102013440501 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Grimaldi L, Papeix C, Hamon Y, Buchard A, Moride Y, Benichou J, Duchemin T, Abenhaim L | title = Vaccines and the Risk of Hospitalization for Multiple Sclerosis Flare-Ups | journal = JAMA Neurology | volume = 80 | issue = 10 | pages = 1098–1104 | date = October 2023 | pmid = 37669073 | pmc = 10481324 | doi = 10.1001/jamaneurol.2023.2968 }}</ref> [[breast feeding]],<ref name="pmid1897097722"/> physical trauma,<ref name="pmid112053612">{{cite journal | vauthors = Martinelli V | title = Trauma, stress and multiple sclerosis | journal = Neurological Sciences | volume = 21 | issue = 4 Suppl 2 | pages = S849–S852 | year = 2000 | pmid = 11205361 | doi = 10.1007/s100720070024 | s2cid = 2376078 }}</ref> and [[Uhthoff's phenomenon]].<ref name="pmid168043312"/>