The sudden outbreak and spread of COVID‐19 in this spring led to a serious challenge to the global public health system. So far, the number of cases in the mainland of China has exceeded 80 000, more than 3000 people died of this disease. The latest data showed that in addition to China's neighboring countries like Japan, South Korea, Thailand and India, severe outbreaks have also occurred in Italy and many other countries around the world. As dated on 12th March, the World Health Organization (WHO) declared that the confirmed cases reported outside China rise to more than 30 000. WHO had announced that “this is not a drill, it's a global pandemic.”

The special expert group for control of the epidemic of novel coronavirus pneumonia of the Chinese Preventive Medicine Association has recently reported the epidemiological characteristics of these cases. 1 The results showed that the cases were concentrated in the age group of 30 to 79 years old, which accounted for more than 85% of the total number of confirmed cases, and the number of cases above 60 years old accounted for 30% to 45%. The crude death rate was 2.3% in all cases, 14.8% in the age group over 80 years old, 2.8% in men, and 1.7% in women, unfortunately, and sadly, more than 3000 Chinese medical staff have been infected. While no epidemiological data on the prevalence and proportion of severe cases in pregnant women have been reported till now.