ABSTRACT
The world has been combating different variants of SARS-COV-19 since its first outbreak in Wuhan city. SARS-COV-19 is caused by the coronavirus. The corona virus mutates and becomes more transmissible than earlier variants as the day passes. Till 24 November 2021, SARS-COV-19 has four variants Alpha, Beta, Gamma, and Delta, respectively. Among them, the delta variant caused severe havoc across the world. South Africa registered a new variant with the World Health Organization (WHO) on 24 November 2021, which is much more transmissible than previous variants. The WHO classified it as a variant of concern (VOC) on 26 November 2021 and called it the Greek letter Omicron (B.1.1.529), the fifteenth letter in the alphabet. Here a serious attempt was made to comprehend the omicron variant's origin, nomenclature, characteristics, mutations, the difference between delta and omicron variant, epidemiology, transmission, clinical features, impact on immunity, immune evasion, vaccines efficacy, etc.
ABSTRACT
A pandemic disease, COVID-19, affecting over 253 million and 5.1 million deaths reported as on November 2021 from across the globe. The worst hit pandemic since a century. Scientists around the world are working towards the development of drugs for its treatment. Several existing antiviral medications have been tried for the same. Among these, Favipiravir, a broad-spectrum antiviral drug originally developed to treat influenza, shows noted activity against an ample range of RNA viruses. It is an oral antiviral drug with good bioavailability found to be effective in the treatment of COVID-19. This drug has acquired FDA manifestation for drug-resistant Influenza as it has confirmed its safety profile. There has been growing evidence that it helps in early viral clearance and speedy symptomatic relief against COVID-19. This review attempts to provide synthetic methods of favipiravir, mechanism of action and its importance in the treatment of COVID-19 and other viruses.