COVID-19 vaccines: A ray of hope

ABSTRACT

Coronavirus-induced disease (COVID-19) has emerged as a dreaded pandemic which is a threat to the entire world. It all began in Wuhan, China, in December 2019 and rapidly spread over the world. It is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) which is an enveloped virus single-stranded, positive-sensed ribonucleic acid virus that enters the host cell lungs via endocytosis or membrane fusion utilizing the ACE-2 receptor. The virus particles release and replicate into new progenies, which cause cytokine storm in some cases by releasing pro-inflammatory mediators into the lungs. It dominantly manifests as SARS-CoV-2 and eventually involves all systems of human body. As of July 15, 2021, approximately 189 million COVID-19-infected cases have been reported worldwide, with over 4 million individuals dying as a result. In India, so far there are approximately 31 million infected cases and 4 lakhs human lives have been lost. Various antivirals, antibiotics, corticosteroids, and other adjuvant therapies were being experimentally employed for COVID-19 prophylaxis and treatment. Many pharmaceutical companies have worked on COVID-19 vaccinations to stop the virus progression and transmission. In several countries, including India, the United States, and Russia, the COVID-19 vaccine has already been approved for human use. India has been able to produce two vaccines, namely Covaxin and Covishield, and launches a massive vaccination drive for people above 18 years adults. Till now, approximately 304 million subjects have been partially vaccinated and 73 million subjects are fully vaccinated. Various other COVID-19 vaccines are in Phase 3 of clinical development. Vaccines against COVID are a major tool against the progression and prevention of COVID-19.