Illustration of the ultrastructure of the SARS-CoV-2 coronavirus (previously 2019-nCoV) that was first identified in Wuhan, China, in December 2019. It is an enveloped RNA (ribonucleic acid) virus. Within the membrane are spike proteins (red), membrane proteins (orange) and envelope proteins (yellow). SARS-CoV-2 causes the respiratory infection Covid-19, which can lead to fatal pneumonia. As of late January 2020, thousands in China have been infected with over 150 deaths, leading to travel restrictions, infection control measures, and cancellation of public celebrations for Chinese New Year, to prevent the spread of the virus.