Based on the currently available literature on rotavirus burden in Western Europe, this analysis revealed that incidence rates for RVGE in the under five year old population ranged between 1.33 and 4.96 cases per 100 person-years [15–19]. However, the incidence rate of RVGE is likely underestimated as many patients receive care at home. Estimation of the proportion of RVGE patients receiving no medical care ranged from 25% to 51% of patients [3, 23, 24]. Accurate estimates of total incidence rates accounting for all these RVGE cases were not possible due to the limited availability of epidemiological data from community-based cohort studies. The incidence of nosocomial infection due to RVGE reported among the hospitalized pediatric population is higher than the incidence reported in community-based studies ranging from 0 to 1.87 cases per 1000 days of hospitalization (0-68.2 per 100 person-years in hospital) depending on the country .
The prevalence of rotavirus infection varied from country to country. Among the pediatric population, community-acquired rotavirus infection accounts for between 25.3% (in Greece) to 63.5% (in Sweden) of acute gastroenteritis cases [77–79]. These variations may reflect actual differences in the proportion of RVGE and incidence of rotaviral disease, however, variations in the design of the studies captured in the review limits comparability across countries. Nosocomial RVGE accounted for between 47% and 69% of all hospital-acquired acute gastroenteritis among hospitalized children except in one study, conducted in France during the peak of the rotavirus season, where 97% of nosocomial diarrhea cases were due to rotavirus [15, 26, 30]. For most countries in Western Europe, the season for RVGE was reported to occur in the winter from December to April or May. A slightly later rotavirus season was noted in Ireland, Greece and Scandinavian countries. Nosocomial infection mirrored the seasonality of the community-acquired disease.
The most commonly isolated genotype combinations in the Western European region were G1P, G2P, and G9P according to the most recent studies available for each country. G2P and G3P were also widespread in the region. Genotype combinations G1P, G4P, G9P, G9P, and G2P were each reported in only one country. Non-typable and partially typed serotypes accounted for between 0.0% and 3.8% of all serotypes in studies where these were reported. In general, the distribution of rotavirus genotype combinations among patients with nosocomial RVGE was very similar to the distribution among patients with community-acquired disease from the same study [15, 25, 30, 49].
While several studies tracked the evolution of genotype distribution and predominance over time, we were not able to discern any overall trends in serotype distribution within the region. This is because serotype predominance appears to change on a season to season basis within each country, and may even differ from region to region within the same country. Emerging rotavirus serotypes were rarely reported in Italy and Spain.
Rotavirus fatalities were rare across the region with less than 10 deaths occurring per year in most countries among children under five years old; therefore, few studies included mortality data for RVGE. Mortality due to nosocomial RVGE was higher, reaching 0.74 per 100,000 children-year among children of less than 12 months of age compared to 0.16 per 100,000 children-year for those < 5 years) . Comparison with a global literature review of mortality due to rotavirus shows that all of the countries in Western Europe have some of the lowest mortality rates globally . A recent literature review of rotavirus burden of illness in the Middle East and North Africa reported annual mortality rates of between 0 and 112 per 100,000 children under five years of age depending on the country .
Resource utilization by rotavirus infected patients is generally higher than for non-RVGE related disease. Hospital admission for gastroenteritis is significantly more likely to happen in RV induced infections than for non-RV related disease  and, when compared to non-RVGE, RVGE is associated with significantly higher disease severity scores [20, 31]. Intravenous rehydration was more commonly administered to patients with acute RVGE in an emergency department or hospital setting, compared to patients with non-rotavirus disease, reflecting the higher level of dehydration in RVGE patients [25, 34]. In addition, hospitalization due to RVGE was longer than for other viral gastroenteritis causes .
Overall, the duration of hospital stay ranged between 2.5 days to 5.0 days for patients with community-acquired RVGE while nosocomial RVGE infection prolonged hospital stay by 4.4 days . However, similar disease severity scores were reported for community-acquired and nosocomial RVGE. Little data is available concerning dehydration in nosocomial cases.
The cost of illness and productivity loss due to RVGE is large. Overall, at the country level, direct medical costs due to RVGE ranged between $543,775 and $53.6 million according to the size of the pediatric population and the type of health care provided, while indirect costs accounted for an additional $1.7 million to $22.4 million, annually [29, 64, 65]. Cost per patient varied by setting, with patients hospitalized for RVGE incurring the highest direct and indirect costs, and patients treated at home incurring the lowest costs; however, data pertaining to the cost of RVGE management among children who do not seek medical care is limited [21, 24, 64, 67, 68].