Is rotavirus still a major cause for diarrheal illness in hospitalized pediatric patients after rotavirus vaccine introduction in the Saudi national immunization program?

Previous studies in Jeddah, western Saudi Arabia, showed rotavirus (RV) prevalence around 40% in pediatric inpatients with gastroenteritis (GE) with a maximum level during cooler months. Currently, there are no data on impact of rotavirus vaccine (RVV) on RV-GE in Saudi Arabia. Therefore, this study was conducted to assess impact of RVV on incidence and severity of RV-GE in hospitalized pediatric patients; 3 years after introduction of RVV in Saudi immunization program (SIP) in January, 2013.This cross-sectional observational study included GE cases under 5 years of age admitted to 2 tertiary hospitals, in Jeddah, from October to December, 2015. All included GE-cases had RV antigen detection in stool by immunochromatographic assay, complete data collection including RVV status and severity assessment (Vesikari score) in initial admission.During study period, a total of 359 GE cases in children under 5 years of age were hospitalized with 14 (3.9%) RV-GE confirmed cases. Mean age of RV-GE patients was 13.10 ± 5.70 months. All RV cases had severe GE and 1 case received RVV. Among other 345 GE cases, 35.7% did not receive RVV and 46.1% had severe GE. Severe GE (Vesikari score > 11) was more significantly identified among RV-GE cases than in other all-cause GE (P < .001). During same period of this study in 2012, 369 RV-GE out of 1193 total GE cases (31%) were hospitalized at 2 hospitals, so, number of hospitalized pediatric patients for all-cause and RV-GE in children under 5 years of age decreased significantly in 2015 RV season (compared to 2015 RV season, odds ratio for RV-GE in 2012: 11.04, 95% CI: 6.38-19.09).Logistic regression analysis of variables of this cross-sectional, hospital-based study in Jeddah, Saudi Arabia, 3 years after introduction of RVV in SIP, showed that among the studied variables, RVV was associated with remarkable reduction of hazard of all-cause and RV-GE in vaccinated and even in unvaccinated children under 5 years of age possibly by RVV herd effect. However, RV was still associated with severe GE-related hospitalizations in unvaccinated children against RV who were younger than 2 years and particularly in the 1st year of life, indicating need for more optimum rate of RVV coverage. Hopefully, further improvement in RVV coverage rate may make RV-GE a disease of the past in Saudi children.