Biology and molecular basis of the pathogenesis and control of corona viruses with a focus of the COVID-19: mini review

ABSTRACT

This brief review, which was presented as an introduction to the CAS/IAP/NASCA Workshop on scientific evidence response to the COVID-19 in Cameroon and Africa, covers the classification of viruses based on the coding nucleic acid type, the structure of the genomes of corona viruses that have infected humans in the 21st century ie SARS-CoV, MERS-CoV and SARS-CoV-2. It is recalled that SARS-CoV-2 has a genome size of 29.8 kb very similar to those of SARS-CoV (29.10 kb) and MERS-CoV (30.1kb). The functions of main proteins featuring on surface the SARS-COV-2, namely, spike (S), membrane (M) and the envelope (E) protein as well as the nucleocapsid (N) protein that is expressed in the core of the viral particle were described. An overview of the pathogenesis showed that the three viruses cause similar symptoms, the most severe of them being the severe respiratory syndrome that could lead to death. A deep understanding of the roles of the viral proteins has facilitated the development of diagnostic tests, vaccines and drugs to combat the COVID-19 pandemic. The review also cites COVID-19 vaccines currently approved by the WHO as well as patent drugs in current usage and points out that none of these were developed in Africa, which is why local capacity has to be built to better combat the current and future pandemics.