Frequent association of multiple sclerosis with varicella and zoster

BACKGROUND: A possible association of multiple sclerosis (MS) with viral diseases has been postulated; in previous studies we have found that in Mexican mestizos the antecedent of varicella during childhood represents a risk factor for the development of MS during adulthood. AIM: We conducted a retrospective search for varicella and zoster infections associated with the development of MS. METHODS AND RESULTS: In a cohort of 82 consecutive patients with MS we found six cases, four of varicella and two of zoster, that were concurrent with the development or the progress of MS. CONCLUSIONS: The association of these pathologies is higher than expected and suggests a possible etiological relationship of the varicella zoster virus with MS.