A study on enhancing the role of clinical pharmacist in antimicrobial stewardship in Kerala vis a vis experiences from South Africa and United Kingdom

Introduction:The mammarenavirus Lassa virus (LASV) infects tens to hundreds of thousands of individuals in Western Africa annually.Approximately 20% of infections results in Lassa fever (LF), an acute disease with an estimated case-fatality rate of up to 26%.LF is characterized by high fever, malaise, myalgia, and gastrointestinal signs.In severe cases, central nervous system involvement and respiratory distress may manifest and progress to shock and death.Due to the potential to cause a public health emergency, the World Health Organization has listed LF as a Priority Disease of Concern.No vaccines or specific therapeutics are approved to prevent or treat LF.Methods: The LASV genome consists of a large (L) segment that encodes two proteins, L and Z, and a small (S) segment that also encodes two proteins, glycoprotein (GP) and nucleoprotein (NP).Genes in each genome segment are separated by a non-coding intergenic region (IGR).Previously, we generated recombinant LASVs (rLASVs) via traditional reverse genetics, in which the L IGR was replaced with the S IGR or in which the GP-encoding gene was codon-deoptimized and showed that both were less fit in vitro and were highly attenuated in vivo.Further, vaccination with these rLASVs protected domesticated guinea pigs from otherwise lethal LASV exposure.Here, we utilize the same approach and report the generation of an rLASV that combines both determinants of attenuation (rLASV/IGR-CD), which further enhances the vaccine safety of its predecessors.Results: rLASV/IGR-CD grew to high titers in Vero cells but did not cause signs of disease or pathological lesions in exposed domesticated guinea pigs.Additionally, and most importantly, animals vaccinated with rLASV/IGR-CD were completely protected from disease and death after a typically lethal exposure to wildtype LASV.Moreover, the animals developed high antibody titers after vaccination and significantly reduced proinflammatory cytokines after exposure.Discussion: The only currently approved effective vaccine against mammarenavirus infection in humans is Candid#1, which uses a live-attenuated strain of Junn virus; Candid#1 is approved for use in Argentina and has investigational new drug status in the U.S. LAVs frequently trigger lasting robust cell-mediated and humoral immune responses.However, concerns about reversion to virulence events (through mutation, recombination, or reassortment with wild-type strains) obligate careful preclinical evaluation of this risk, that, at minimum, establishes an extremely low likelihood of reversion.Conclusion: Our previous findings, together with the data presented here, indicate that the incorporation of genetic determinants of attenuation in both the S segment and L segment is an attractive approach to develop mammarenavirus LAV candidates.Our data support the development of rLASV/IGR-CD to solidify a foundation for the creation of a live-attenuated LF vaccine with unassailable safety features.