1. Distrito Sanitario de Atención Primaria, Almería, Spain
2. Escuela Andaluza de Salud Pública, University of Granada, Granada, Spain
3. Center for Biomedical Research Network in Epidemiology and Public Health, Madrid, Spain
4. Institute of Biomedical Research Granada, University Hospitals of Granada, University of Granada, Granada, Spain
5. Vaccine Research Department, FISABIO-Public Health, Valencia, Spain
6. Department of Public Health, University of Copenhagen, Copenhagen, Denmark
7. Unidad de Inmunología, Hospital Torrecardenas, Almería, Spain
8. Centro de Salud Colonia de Santa Ines, Distrito Sanitario de Atención Primaria Guadalhorce, Málaga, Spain
9. CAP St Ildefons, Cornellà de Llobregat, Barcelona, Spain
10. Instituto Hispalense de Pediatría, Instituto Balmis de Vacunas, Almeria, Spain