Based on the current information, most patients had a good prognosis, while a few patients were in critical condition, especially the elderly and those with chronic underlying diseases. As of 1 March 2020, a total of 79,968 confirmed cases, including 14,475 (18.1%) with severe illness, and 2873 deaths (3.5%) in mainland China had been reported by WHO [2]. Complications included acute respiratory distress syndrome (ARDS), arrhythmia, shock [46], acute kidney injury, acute cardiac injury, liver dysfunction and secondary infection [48]. The poor clinical outcome was related to disease severity. The disease tends to progress faster in elderly people, with the median number of days from the occurrence of the first symptoms to death shorter among people aged 65 years or more [56, 57]. Similar to H7N9 patients [58], the elderly male with comorbidities and ARDS showed a higher death risk. Additionally, more than 100 children were infected, with the youngest being 30 h after birth [59]. Neonates and the elderly need more attention and care due to their immature or weak immune system.