Monitoring of measles elimination using molecular epidemiology

The different measles virus genotypes are confined to more or less distinct geographic regions. Molecular characterization of virus isolates has been successfully used to determine epidemiological links between cases and the geographic origin of imported viruses. In Europe. indigenous measles has be en eliminated in some countries, but in others the disease is still endemic . Intra-outbreak variability can be used to differentiate between sporadic endemic cases and a 'pseudo-outbreak' of unrelated imported cases. The inte rruption of virus circulation by mass vaccination campaigns could be demons trated by comparing the variability of pre-campaign viruses with post-campa ign isolates. Simplified tools are being developed that could bring genotyp ing within reach of laboratories that do not have the possibility of sequen cing. (C) 2001 Elsevier Science Ltd. All rights reserved.