Combination of two rare mutations in the SARS-CoV-2 M gene in patients with severe and prolonged COVID-19.

Background: The SARS-CoV-2 virus significantly changed our knowledge about coronaviruses. The interplay between SARS-CoV-2 and the human host, the infection ranges from asymptomatic to lethal, and differences in the degree of disease severity are important examples.

Methods: In this retrospective study, 24 nasopharyngeal swabs from 21 out of 457 patients with SARS-CoV-2 infection were analysed by whole-genome sequencing.