Measles genotypes D4 and G3 reintroduced by multiple foci after 15 years without measles virus circulation, Gipuzkoa, the Basque Country, Spain, March to June 2011

1. Cilla, G.
2. Montes, M.
3. Artieda, J.
4. Piñeiro, L.
5. Arriola, L.
6. Pérez-Trallero, E.