| report of varicella outbreak in a low vaccination coverage group of otherwise healthy children in italy: the role of breakthrough and the need of a second dose of vaccine. | we describe an outbreak of varicella at a preschool center in southern italy, in the period january-may 2009, among children with a vaccination coverage of 53.9% for one dose. the outbreak occurred in a small community in puglia and enrolled 41 children. the attack rates for unvaccinated and vaccinated children were 72.3% and 12.7%, respectively. the vaccine effectiveness against disease was 82.4%. our findings add a further piece of evidence in supporting the routine use of a second dose of vac ... | 2010 | 19961965 |