An international team involving researchers from the Institute of Virology and Immunology (IVI) of the Federal Food Safety and Veterinary Office BLV and the University of Bern, the Centers for Disease Control and Prevention (USA), and the Friedrich-Loeffler Institute (Germany), has developed an approach that can accurately assess the transmissibility of new virus mutants.
This new approach can be used to test any single mutation or a specific combination of mutations that are present in a number of currently circulating viral variants. The IVI relies on a cloning technique developed in Bern a year ago, in which SARS-CoV-2 viruses can be exactly reproduced in the laboratory. The British virus, for example, is known to have not just one but often more than 14 mutations, eight of which occur in the spike protein.
Therefore, with the help of the cloning technique, any number of mutations of variants can be reproduced and used to compete against each other in the established cell cultures and animal models. The results show how single mutations affect the fitness and transmissibility of new variants.
Similar research projects on infectious pathogens could also be carried out in the future at the newly established Multidisciplinary Center for Infectious Diseases and Immunity (MCIDI) at the University of Bern. Currently, the IVI is the only high-security laboratory in Switzerland where highly contagious animal diseases (such as foot-and-mouth disease or swine fever) can be diagnosed and researched.