Epstein-Barr virus may increase MS risk

PAST infection with Epstein-Barr virus (EBV) may increase a person's risk of developing multiple sclerosis (MS) if they have certain genetic variations, Australian research shows.

In a case-control study, researchers led by a team from the Australian National University (ANU) found the presence of EBV antibodies and a history of infectious mononucleosis was related to an increased risk of demyelinating disease, an association consistent with other, previous studies.

In addition, the researchers showed specific genetic mutations (HLA-DR15 or HLA-A genotype) increased the risk of a first demyelinating event about 20-fold.

"This work is really encouraging, as it starts to bring together the different risk factors that we know are involved in MS," lead author Associate Professor Robyn Lucas said.

"It points us in the right director for further research to prevent and cure MS."

No evidence was found that a current EBV DNA load in the blood increased CNS demyelination, and no evidence was found of an interaction with other risk factors such as vitamin D status or past sun exposure.

"Strengths of this multicentre study include recruitment of incident cases from study regions spanning a wide latitude range, the examination of a broad spectrum of environmental factors, and the measurement of quantitative EBV DNA load and titres for 4 EBV-specific antibodies," the authors said.

The research is part of the Ausimmune Study, funded by the NHMRC and charities, and involved nearly 300 EBV cases aged 18-59 years and 550 age, sex and region-matched controls.

Neurology 2011, online 13 July