摘要
1.Introduction.Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection has led to the outbreak of COVID-19 syndrome since December 2019,becoming prevalent worldwide afterward[1,2].Unlike severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS),which cause severe symptoms and high mortality[1],the morbidity from COVID-19 is relatively low,especially in young people[3].In China,the mortality rate was 1023 of 44,672 confirmed cases by the end of Februaryl 1,2020[4].However,there were no cases of death among 416 patients aged 0-9 years,and only 1 in 549 patients aged 10-19 years[4].The exact reasons for this clinical phenomenon remain unclear.
基金
the Chinese National Mega Science and Technology Program on Infectious Diseases(2018ZX10731301-001-004)
Science and Technology Commission of Shanghai Municipality(20JC1410200)
Shanghai Academic Research Leader Project(2018XD1403300)
Shanghai Municipal Commission of Economic and Informatization(GYQJ-2020-FY-06)
the Emergency Project of Shanghai Institute of Immunology.
