Real-World Effectiveness of Pentavalent Rotavirus Vaccine among Bedouin and Jewish Children in Southern Israel

Background. Pentavalent rotavirus vaccine (RV5) was introduced into the Israeli National Immunization Program in January 2011. We determined RV5 vaccine effectiveness (VE) in southern Israel, a region characterized by 2 distinct populations: Bedouins living in a low- to middle-income, semirural setting, and Jews living in a high-income, urban setting. Methods. We enrolled vaccine-eligible children who visited the emergency department (ED) or were hospitalized due to acute gastroenteritis (AGE) during the first 3 rotavirus seasons after RV5 vaccine introduction (2011-2013). Fecal specimens were tested for rotavirus by enzyme immunoassay and genotyped. Vaccination among laboratory-confirmed rotavirus cases was compared with rotavirus-negative AGE controls. Regression models were used to calculate VE estimates by age, clinical setting, and ethnicity. Results. Of 515 enrolled patients, 359 (70%) were Bedouin. Overall, 185 (36%) patients were rotavirus positive; 79 of 119 (66%) were G1P[8] genotype. The adjusted VE for a full 3-dose course of RV5 against ED visit or hospitalization was 63% (95% confidence interval [CI], 38%-78%). RV5 provided G1P[8] genotype-specific effectiveness of 78% (95% CI, 58%-88%). By age, RV5 VE was 64% (95% CI, 21%-84%) and 71% (95% CI, 39%-86%) among children aged 6-11 months and 12-23 months, respectively. By clinical setting, RV5 VE was 59% (95% CI, 23%-78%) against hospitalization, and 67% (95% CI, 11%-88%) against ED visit. The adjusted VE of a full RV5 course among Bedouin children was 62% (95% CI, 29%-79%). Conclusions. RV5 significantly protected against rotavirus-associated ED visits and hospitalizations in a diverse population of vaccine-eligible children living in southern Israel.