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Abstract RV is one of the commonest viruses causes a severe diarrhealillness, especially in children under age of 5 years. RVGE is selflimiting illness; however, death of untreated cases with severe dehydration might be resulted. RV-related death is more common in developing-African countries, where individual income and healthcare is limited. To protect against RV complications and deaths, RV vaccination in neonatal-life is strongly recommended. Currently, variant attenuated RV vaccines have been approved for immunization against RVGE, as Rotarix® and Rotateq®. The RV immunization with attenuated vaccines in African countries is restricted as result of the vaccine efficacy limitation among these populations; high vaccination cost, which does not match the individual income there; immunodeficiency/ malnutrition problems in most African children, so constricted administration of activevirus vaccines; intussusception side effect that is a life-threatening condition; and virus reassortment events that might develop a novel RV strains with un-expected pathogenicity. To bypass most of these current frailties those related mostly to the active-virus presence, the alternative inactivated-RV vaccination approach was endorsed Dependently, the goal of the present study is to develop a pentavalent-IRVV that containing the most circulating RV strains within the Egyptian environment. Moreover, evaluating its effectiveness compared to a currently used attenuated vaccine. The designed-IRVV antigen pool were including G1/G2/G3/G9/P[8] antigens. That was achieved by isolating RV strains that having the selected G/P antigens from RV-positive fecal samples. These samples were collected from children hospitalized with severe gastroenteritis. The experimental preparation and formulation of the thermallytreated RV vaccine was performed using the produced antigens pool. As an attempt for improving the IRVV immunogenicity, Alumadjuvant was added. The experimental IRVV/ IRVV-Alum immune potential was evaluated using the mice model. While three equal doses of Alum adsorbed and non-Alum adsorbed IRVV were injected subcutaneously at 0, 21, 35 time intervals, the reference Rotarix® group was vaccinated twice at 0, 28 time intervals. The collected sera were processed using ELISA technique for evaluating RV specific-IgG that reflect the established immunogenicity against RVI. As result of the trial IRVV/ Rotarix® difference in antigenic content and doses regimen, the comparative evaluation was reliant on achieving the IgG immunization level of 1:6400.Accordingly, we concluded that, the IRVV could be an acceptable strategy to reach the immunization level against RVI (IgG titer >1:6400), however the incorporation of adjuvant system could perfectly modulate the developed immunity to be long lasting and stronger. That’s by keeping the immunization elements as the IgG antibodies more elevated for longer time. The Rotarix® vaccination also could increase the IgG antibodies than that indicated limit (IgG titer >1:6400), but the inactivated vaccine could bypass other limitations that associated with the attenuated approach. These limitation are efficacy variation among population, intussusception risk and unintended vaccine/ wild strains reassortment. Besides that, the inactivated vaccines could solve the cost problem that facing the attenuated vaccination. The wide mass production and public vaccination could be achieved more easily, especially for the poor African countries, which are more susceptible for RV death, using the inactivated RV vaccination. |