Abstract
Multiple sclerosis (MS) is multifactorial disease influenced by genetic, immunological, hormonal and environmental factors. Involvement of viral infections in MS triggering and development is considered.
There is no clear evidence of causal role of viruses in MS pathophysiology nevertheless their involvement in neuroimmune system modulation in susceptible individuals is well known. Several hypothesis of viral involvement in MS immunological processes is investigated (molecular mimicry, bystander activation, epitop spreading, "fertile field" theory or theory of "déja vu").
A number of viruses can be directly or indirectly connected with the pathogenesis of MS (herpesviruses, adenoviruses, papilomaviruses, polyomaviruses, hepadnaviruses, lymphocytic choriomeningitis virus, some of flaviviruses and bunyaviruses). On the other hand, using of modern immunomodulating drugs can be a risk for latent virus reactivation.
Therefore appropriate drug therapy for each patient should be considered individually with careful assessment of all known risks.