Seroprevalence of herpes simplex virus type 2 in multiple sclerosis

Background – It has been proposed that multiple sclerosis (MS) might be a sexually transmitted disorder. There is evidence that seropositivity to herpes simplex virus type 2 (HSV-2) correlates well with the number of sexual partners. Accordingly, a raised overall HSV-2 seroprevalence in MS would lend support to this theory. Materials and methods – Serum from 497 UK subjects with clinically definite MS was tested for antibodies to HSV-2 and compared with matched historical controls from within and outside London, blood donors and genito-urinary medicine (GUM) clinics. Results – The unadjusted MS seropositivity rate was 14%. HSV-2 seroprevalence in MS patients aged 35–64 years was significantly higher overall compared with a non-London general population in an unadjusted comparison. HSV-2 seroprevalence in London MS patients compared with London blood donors was significantly greater irrespective of age, but the MS seropositive rate was lower than GUM clinic attenders. In a logistic regression analysis, increased age, female sex and MS diagnosis all independently increased the odds of seropositivity after adjustment for each other. Conclusion – It is concluded that there is increased likelihood of HSV-2 exposure in patients with MS and this may indicate a higher than average number of partners.