The IBV-like novel cold viruses looked like the mouse hepatitis virus. This new group of viruses were called "coronaviruses" from their crown-like appearance. The coronavirus strain B814 was lost. It is not known which present human coronavirus it was. Other human coronaviruses have since been identified, including SARS-CoV in 2003, HCoV NL63 in 2003, HCoV HKU1 in 2004, MERS-CoV in 2013, and SARS-CoV-2 in 2019. There have been a large number of animal coronaviruses identified since the 1960s.