To deal with this problem, a highly conserved sequence-specific vaccine target should be designed to gain effective vaccine strategies. A study conducted in India followed the children from birth for three years and concluded that 63% of children who suffered from RV experienced at least three infections before reaching their third birthday. This genetic variation of Rotaviruses is a consequence of repeated infection in children, especially in impoverished settings. Therefore, the efficacy of live attenuated vaccines to provide immunity against all G and P types as well as against any unusual strain in case of an outbreak is of great question. Similarly, vaccine-induced immune pressure can also be involved in the emergence of novel RV strains which may cause serious illness even in vaccinated children. The segmented genome nature of RVA and its multiple host range causes a high frequency of genetic reassortment and interspecies transmission to form a novel genotype. Vaccine efficacy of RotaTeq is reported to be 45% in higher mortality rate countries and 90% in lower mortality rate countries, while the Rotarix vaccine efficacy is reported to be 57% in high mortality rate countries, 75% in medium and 84% in lower mortality rate countries. RotaTeq is a pentavalent vaccine (G1P, G2P, G3P, G4P, and G6P ) while Rotarix is a monovalent vaccine (G1P ). ![]() Currently, 123 countries have already introduced the vaccine into their population including Pakistan which has introduced the Rotarix vaccine into its Extended Program on Immunization (EPI) initially as a phased introduction at a subnational level in five districts of the province of Punjab and then at the national level in 2018. In 2009, the WHO recommended introducing the two live attenuated RVA Vaccines (RotaTeq: Merck & Co, Rotarix: GlaxoSmithKline) into their routine immunization program globally. However, this vaccine gave way to many more attempts. To counter the colossal rate of RV infections, a live attenuated vaccine named Rotashield was introduced in 1998 but soon due to intussusception cases and the poor effectiveness of the vaccine, it was taken off. These computational findings show potential against all RVA genotypes however, in-vitro/in-vivo screening is essential to devise a meticulous conclusion. The population coverage analysis showed 99.0% and 98.47% in South Asia and worldwide, respectively. Codon optimization was performed with an adenovirus vector in a mammalian expression system. In the MD simulation, the RMSD value varied from 0.2 to 1.6 nm while the minimum integrin amino acid fluctuation (0.05–0.1 nm) was observed with its respective ligand. Immune simulation displayed promising results both in Asia and worldwide. The 3D structure was predicted and refined preceding its docking with integrin. The vaccine contains four B-cell, three CTL and three HTL epitopes joined via linkers and an N-terminal RGD motif adjuvant. Epitopes were screened for antigenicity, allergenicity, homology with humans and anti-inflammatory properties. In the present study, a multivalent vaccine was designed from VP4 and VP7 proteins of RVA. ![]() ![]() There are concerns that monovalent (Rotarix: GlaxoSmithKline Biologicals, Rixensart, Belgium) and pentavalent (RotaTeq: MERCK & Co., Inc., Kenilworth, NJ, USA) vaccines may be less effective against non-vaccine strains, which clearly shows the demand for the design of a vaccine that is equally effective against all circulating genotypes. Due to a segmented genome, there is a high frequency of genetic reassortment and interspecies transmission which has resulted in the emergence of novel genotypes. Rotavirus A is the most common cause of Acute Gastroenteritis globally among children <5 years of age.
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