A considerable proportion of individuals with asymptomatic SARS-CoV-2 infection in Tibetan population

Song, Huan; Xiao, Jun; Qiu, Jiajun; Yin, Jin; Yang, Huazhen; Shi, Rui; Zhang, Wei

Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) quickly became a major epidemic threat in the whole China. We analysed SARS-Cov-2 infected cases from Tibetan Autonomous Prefecture, and noted divergent characteristics of these Tibetans infected cases compared to Han Chinese, characterizing by a considerable proportion of asymptomatic carriers (21.7%), and few symptomatic patients with initial symptom of fever (7.7%). Here, we did a descriptive study on clinical characteristics of 18 asymptomatic individuals with SARS-CoV-2 infection. The median age of these asymptomatic carriers was 31 years and one third of them were students, aged under 20 years. Notably, some of asymptomatic carriers had recognizable changes in radiological and laboratory indexes. Our finding indicates a potentially big number of SARS-CoV-2 asymptomatic carriers in prevalent area, highlighting a necessity of screening individuals with close contact of infected patients, for a better control on the spread of SARS-CoV-2 infection.