Molecular epidemiology of SARS-CoV-2: a review of current data on genetic variability of the virus

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2), associated with coronavirus disease 2019 (COVID‑19), is a novel pathogen recently introduced to the human population. It is characterized by rapid epidemic transmissions due to lack of herd immunity as well as by notable mortality which increases with age and in patients with comorbidities. Outbreak forecasting and modelling suggest that the number of infected people will continue to rise globally in the forthcoming months. Upon investigation of the disease patterns, differences in mortality between south‑European and north‑European countries became striking with mortality of more than 10% in Italy and Spain and less than 5% in Germany and Poland so far. It is unknown if this difference is associated with a higher virulence of viral strains, differences in host genomics, access to medical resources, or other unknown variables. Little is also known about SARS‑CoV‑2 evolutionary and transmission patterns as a limited number of large‑scale sequence and phylogenetic analyses have been performed so far. In this review, we aimed to provide concise data on the SARS‑CoV‑2 genomics, molecular evolution, and variability with special consideration of the disease course.