Epstein-Barr virus genotypes and strains in central nervous system demyelinating disease and Epstein-Barr virus-related illnesses in Australia

Objectives: To identify Epstein-Barr virus (EBV) genotypes and strains in samples from individuals with and without a first diagnosis of central nervous system (CNS) demyelinating disease (a possible precursor to multiple sclerosis) and patients with EBV-associated diseases in Australia. Methods: Samples from 55 EBV DNA and serology positive subjects including individuals with (n = 17) and without (n = 21) a first clinical diagnosis of CNS demyelination and patients with EBV-related diseases (n = 17) were examined. EBV genotype and strain were identified by sequence mutations within the Epstein-Barr nuclear antigen-2 region (EBNA-2) using DNA sequence analysis. Results: Both EBV genotypes, A and B, were detected (genotype A, 54/55, 98.2%; genotype B, 1/55, 1.8%). Within genotype A, GD1 was the most commonly detected strain (42/54, 77.7%), followed by B95-8 (9/54, 16.7%) and M-ABA (3/54, 5.6%). Genotype B, strain AG876, was found in one individual with CNS demyelinating disease. Conclusions: EBV genotype A and the GD1 strain were the common EBV genotypes isolated from individuals with and without CNS demyelinating disease, and in subjects with various EBV-related diseases. Although disease-specific genotypes or strains were not identified, this study provides useful insights into the molecular epidemiology of EBV infection in Australia.