Background Rotavirus (RV) is the most common cause of gastroenteritis (GE) among children under 5 years. Since 2012 Friuli Venezia Giulia (FVG) Region (Italy) has offered free RV vaccination to low birthweight preterm and other at-risk babies. Starting from 2018, the offer has been extended to all newborns. Aim of the study is to investigate the effectiveness of RV vaccination offer on coverage and GE-related hospital admissions among FVG children under 1 year between 2010-2018. Methods With a retrospective analysis we identified FVG Region children <1y with at least one dose of RV vaccine and children <1y admitted to hospital with a diagnosis of Non-Specific GE (NSGE; ICD9-CM codes 001-009) and RVGE (008.61) from 2010 to 2018. Vaccination coverage and hospitalization risk in each annual child cohort were calculated. Hospitalization and vaccination data were also linked using a univocal anonymous stochastic key. Results Of 77,330 children (51% males) born in FVG during 2010-2018, 8209 (11%) were vaccinated for RV. Coverage progressively increased from 0.2% in 2010 (22/9736) to 23% in 2017 (1782/7747) and then almost tripled in 2018 reaching 67% (5006/7425). During the 9 years observed, 414 children were hospitalized for NSGE (0.5%) and 172 for RVGE (0.2%). NSGE hospitalizations started from 48 (0.5%) in 2010 and reached 58 (0.8%) in 2018. Admissions for RVGE were 27 (0.3%) in 2010 and decreased to 15 (0.2%) in 2018. Annual hospitalization rate fluctuated with no clear pattern. In the observation period, 11 RV vaccinated children were admitted to hospital for NSGE (2.6% of total NSGE admissions), 1 of them specifically with RVGE. Conclusions The offer of RV vaccination to newborns results to be effective to gain vaccine coverage among children under 5 years. The impact of this offer on GE-related hospital admission and RVGE in particular cannot be properly evaluated yet, as not enough time has passed since the implementation of free offer to all newborns. Key messages Defining and implementing an appropriate vaccination offer is essential to ensure adequate levels of coverage against Rotavirus among children under 5 years. The evaluation of the effect of Rotavirus vaccination on hospital admissions for NSGE and RVGE needs a careful and continuous assessment in next years.
