Higher vaccine effectiveness in seasons with predominant circulation of seasonal influenza A(H1N1) than in A(H3N2) seasons: Test-negative case-control studies using surveillance data, Spain, 2003-2011

1. Savulescu, C.
2. Jiménez-Jorge, S.
3. Delgado-Sanz, C.
4. de Mateo, S.
5. Pozo, F.
6. Casas, I.
7. Larrauri, A.