COVID-19 vaccines: rapid development, implications, challenges and future prospects

Abstract

COVID-19 has affected millions of people and put an unparalleled burden on healthcare systems as well as economies throughout the world. Currently, there is no decisive therapy for COVID-19 or related complications. The only hope to mitigate this pandemic is through vaccines. The COVID-19 vaccines are being developed rapidly, compared to traditional vaccines, and are being approved via Emergency Use Authorization (EUA) worldwide. So far, there are 232 vaccine candidates. One hundred and seventy-two are in preclinical development and 60 in clinical development, of which 9 are approved under EUA by different countries. This includes the United Kingdom (UK), United States of America (USA), Canada, Russia, China, and India. Distributing vaccination to all, with a safe and efficacious vaccine is the leading priority for all nations to combat this COVID-19 pandemic. However, the current accelerated process of COVID-19 vaccine development and EUA has many unanswered questions. In addition, the change in strain of SARS-CoV-2 in UK and South Africa, and its increasing spread across the world have raised more challenges, both for the vaccine developers as well as the governments across the world. In this review, we have discussed the different type of vaccines with examples of COVID-19 vaccines, their rapid development compared to the traditional vaccine, associated challenges, and future prospects.

COVID-19 vaccine hesitancy among undergraduate medical students: results from a nationwide survey in India

“…6 The COVID-19 pandemic spurred the rapid development of COVID-19 vaccines with their prominent coverage in news and social media. 7 Recent studies highlighted the concerns regarding adverse events, unduly rapid vaccine development and poor vaccine efficacy as some of the possible reasons for vaccine hesitancy among medical students. 8–12 In the Indian situation, out of the two vaccines, the safety and phase 3 efficacy data was publicly released only for Covishield through a scientific publication of the parent Astra Zeneca vaccine.…”

Assessing school-based policy actions for COVID-19: An agent-based analysis of incremental infection risk

“…Achieving herd immunity is still a challenge considering individuals who are either not eligible to receive the vaccine or decline to be immunized [ 2 ] , and is unlikely to be achieved in some countries such as the US [ 3 ]. Furthermore, recent changes in the strain of SARS-CoV-2 in the United Kingdom, South Africa, and India, as well as its increasing propagation across the globe, have posed new challenges for countries – even ones with high rates of vaccination – to return to normal [ 4 , 5 ]. Therefore, providing impactful non-pharmaceutical interventions and guidelines is, and will remain, of importance.…”

An outlook on antigen-specific adoptive immunotherapy for viral infections with a focus on COVID-19

“…As of the onset of SARS-CoV2 pandemic, many research institutes, big pharma companies and biotechnology firms have synergized their capacities to develop efficient vaccines, and over 80 candidate vaccines have progressed into clinical trials, so far ( Fig 2 and Supplementary material 1 ), meanwhile some of them have led to promising results [19] , [32] . To date, 12 vaccines have received emergency use authorization or full approval in different countries ( Fig 2 ), and early appraisals of the efficacy of some of them have unveiled rates above 70% [19] , [33] .…”

“…In order to empower the body's immune system to effectively tackle the virus, the most common approach is vaccination. While some trialed SARS-CoV2 vaccines have demonstrated promising efficacy [19] , there have been safety concerns and doubts on durability of the post-vaccination immune response in the recipients [20] , [21] . In the recent months, suspected vaccine-induced coagulopathies were on the agenda of regulatory agencies [22] , [23] .…”