Varicella vaccination coverage inverse correlation with varicella hospitalizations in Spain

Varicella vaccines available in Spain were marketed in 1998 and 2003 for non-routine use. Since 2006 some regions included universal varicella vaccination in their regional routine vaccination programs at 15-18 months of age. Regions without universal vaccination in toddlers, but instead with the strategy of vaccinating susceptible adolescents, reached different varicella vaccination coverage through private market. This study shows the correlation between severe varicella zoster virus infections requiring hospitalization and the varicella vaccination coverage by region. A total of 3009 hospital discharges related to varicella were reported in 2009-2010. The overall annual rate of hospitalization was 3.27 cases per 100,000. In children younger than 5 years old varicella hospitalization rate was 30.73 cases per 100,000. Varicella related hospitalizations were significantly lower in the regions with universal vaccination. In those regions without universal vaccination at 15-18 months of age, those with higher coverage in private market showed lower hospitalization rates.