1. Vaccines, GSK, Rockville , Maryland, US
2. VL-Medi Clinical Research Center , Helsinki , Finland
3. Departments of Pediatrics and Microbiology, University of Alabama at Birmingham , Birmingham, US
4. Vaccines, GSK , Rixensart, Belgium
5. Vaccines, GSK , Wavre , Belgium
6. Vaccines, GSK , Siena , Italy
7. Center for Research on Population Health, National Institute of Public Health , Cuernavaca , Mexico