新冠病毒 3D模型

For the ongoing outbreak of coronavirus disease 2019, see 201920 coronavirus outbreak. For the virus strain causing this outbreak, see Severe acute respiratory syndrome coronavirus 2. Coronaviruses are a group of viruses that cause diseases in mammals and birds. In humans, coronaviruses cause respiratory tract infections that are typically mild, such as the common cold, though rarer forms such as SARS, MERS and COVID-19 can be lethal. Symptoms vary in other species: in chickens, they cause an upper respiratory tract disease, while in cows and pigs they cause diarrhea. There are yet to be vaccines or antiviral drugs to prevent or treat human coronavirus infections.