For RV1, the two dose schedule was given at 10 and 14 weeks of age. No efficacy data for RV1 with the recommended 6 and 10 week schedule is available, and it is possible that the efficacy may be lower than that observed with the 10 and 14 week schedule due to higher maternal antibody and potential interference by first oral polio vaccine dose. The efficacy
of three doses of RV5 administered at 6, 10, and 14 weeks of age in Africa (Ghana, Kenya, and Mali) was 64% (95% CI: 40–79%) and in Asia (Bangladesh and Vietnam) was 51% (95% CI: 13–73%) against severe rotavirus disease during the first year of life [21] and [22]. As seen for RV1, RV5 efficacy appeared to decline during the second year of life and was 20% (95% CI: −16 to 44%) in
Africa and 46% (95% CI: 1–71%) in Asia [21] and [22]. Despite lower efficacy in low Cobimetinib income countries, the significant disease burden in these settings results in a greater absolute number of rotavirus cases Nutlin-3a order prevented per 100 vaccinated children compared with higher income countries with lower disease burden. In clinical trials, RV1 efficacy during the first year of life in South Africa (77%) was higher than in Malawi (49%) but the vaccine prevented seven episodes of severe rotavirus gastroenteritis per 100 vaccinated infants in Malawi compared with four episodes prevented per unless 100 vaccinated infants
in South Africa due to the higher disease burden in Malawi compared with South Africa [18]. Rotavirus vaccines have had a notable impact on mortality, hospitalizations and outpatient visits in countries that have introduced the vaccine into their national immunization programme, including some evidence suggesting that rotavirus vaccines may offer indirect protection to older, unvaccinated age groups. Perhaps the most exciting post-licensure data pertains to the effect of rotavirus vaccination in reducing deaths from childhood diarrhea in some countries in Latin America, as the mortality benefits of vaccination were not assessed in pre-licensure trials. In Mexico, following RV1 introduction into the national immunization programme in 2007, the diarrhea mortality rate declined to 35% (95% CI: 29–39%) in 2008 compared with the pre-vaccine baseline (2003–2006): the decline in mortality has been sustained for three years from 2008 to 2010 [23] and [24]. Brazil saw a similar decline of 22–41% in diarrhea mortality rates among children <5 years of age following the introduction of RV1 into the national immunization program in 2006 [25] and [26] (Fig. 2).