SARS-CoV-2: Unique Challenges of the Virus and Vaccines

Abstract

In November 2019, the highly infectious coronavirus SARS-CoV-2 emerged in Wuhan, China, and has since spread to almost all countries worldwide. Since its emergence, the COVID-19 infection has led to significant public health, economic and social problems. The current pandemic has inspired researchers to make every effort to design and develop an effective COVID-19 vaccine to provide sufficient protection against the virus and control the infection. In December 2020, the Pfizer vaccine was the first COVID-19 vaccine given Emergency Use Authorization (EUA), and the second FDA so-approved vaccine was the Moderna mRNA-1273 vaccine, which was introduced a week later. Both Pfizer and Moderna vaccines are mRNA-based vaccines, and are estimated to have an efficacy rate of more than 94%. The aim of this article is to provide a review of the attempts made to develop safe SARS-CoV-2 vaccines, highlighting potential challenges and concerns, such as disease enhancement, virus mutations, and public acceptance of the vaccine.

A modified porous silicon microparticle potentiates protective systemic and mucosal immunity for SARS-CoV-2 subunit vaccine

“…Furthermore, there is a potential concern of “vaccine-induced disease enhancement”, which was reported for certain SARS-CoV vaccine candidates [12] and inactivated RSV vaccines [55] . The potential risk of ADE mediated by Fc-receptor could be increased due to waning immunity after vaccination and possibly mutations in the SARS-CoV-2 S protein [56] . Due to the above concerns, the optimal COVID-19 vaccines will need to exhibit long-lasting immunity, be effective for various populations globally, and provide cross-reactive protection against emerging variants.…”

Effect of cannabidiol on apoptosis and cellular interferon and interferon-stimulated gene responses to the SARS-CoV-2 genes ORF8, ORF10 and M protein

“…Host replication is also needed to produce a sufficient concentration of viral particles for an individual to become infectious to others in a population [ 56 ]. Within a population, widespread replication leads to mutations and the generation of novel variants, which can alter the infectivity and virulence of a virus, and potentially reduce the protective efficacy of vaccines [ 57 ].…”

Effect of cannabidiol on apoptosis and cellular interferon and interferon-stimulated gene responses to the SARS-CoV-2 genes ORF8, ORF10 and M protein

“…Host replication is also needed to produce a sufficient concentration of viral particles for an individual to become infectious to others in a population [54]. Within a population, widespread replication leads to mutations and the generation of novel variants, which can alter the infectivity and virulence of a virus, and potentially reduce the protective efficacy of vaccines [55].…”