Zoonotic transmission of coronaviruses

Coronaviruses have received considerable attention since the emergence of SARS-CoV in China 2002/2003. SARS-CoV infection in people exemplified that coronaviruses can cross the species barrier from an animal reservoir to humans and cause severe and lethal disease in humans. The emergence of MERS-CoV in 2012 showed that zoonotic transmission of coronaviruses is not a rare event. Both viruses have close relatives in bats, and moreover, intermediate hosts, such as racoon dogs, civet cats (SARS-CoV) and dromedary camels (MERS-CoV) have been proposed to facilitate zoonotic transmission. The discovery that dromedary camels harbour MERSCoV and may act as a bridge reservoir between bats and humans provides an important paradigm for the ecology of viral emergence.Interestingly, the human coronavirus 229E (HCoV-229E; causing common cold in humans), appears to have a similar history of zoonotic transmission, since close relatives were detected in bats as well as in camelid species (alpacas and dromedary camels). While MERS-CoV has a very recent history of zoonotic transmission and differences between viruses isolated from humans and camels are rather small, camel-229E-like-CoV and HCoV-229E have alreadydiverged considerably. The aim of the proposed project is to identify and characterize critical species barriers of CoV zoonotic transmission by using the HCoV-229E system as a model. Keywords Coronaviren; Speziesbarriere; Zoonose Hauptdisziplin Strukturforschung