Explained: Types of human coronaviruses and the symptoms they cause

While there are hundreds of coronaviruses, there are seven that we know can infect humans.

While there are hundreds of coronaviruses that cause diseases in animals such as pigs, camels, bats and cats, till date seven different types of coronaviruses have been identified that infect humans. What are they and what kind of symptoms do they cause? Coronaviruses are a large family of single-stranded RNA viruses that cause diseases in animals and humans. In humans, the viruses usually cause mild to moderate upper-respiratory tract illnesses such as the common cold. In the last two decades, more aggressive coronaviruses have emerged that are capable of causing serious illness and even death in humans. These include SARS-CoV, MERS and now SARS-CoV-2.