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Asymptomatic COVID-19 infection: diagnosis, transmission, population characteristics
  1. Yaxian You1,2,
  2. Xinyuan Yang1,2,
  3. Dongni Hung1,2,
  4. Qianxi Yang1,2,
  5. Ting Wu1,3 and
  6. Meichun Deng1,2,4
  1. 1Department of Biochemistry and Molecular Biology & Hunan Province Key Laboratory of Basic and Applied Hematology, School of Life Sciences, Central South University, Changsha, Hunan, China
  2. 2Xiangya School of Medicine, Central South University, Changsha, Hunan, China
  3. 3Department of Cardiovascular Medicine, The Third Xiangya Hospita, Central South University, Changsha, Hunan, China
  4. 4Hunan Key Laboratory of Animal Models for Human Diseases, Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
  1. Correspondence to Dr Meichun Deng, Central South University, Changsha 410013, Hunan, China; dengmch{at}


A novel coronavirus first discovered in late December 2019 has spread to many countries around the world. An increasing number of asymptomatic patients have been reported and their ability to spread the virus has been proven. This brings major challenges to the control of the transmission. The discovery and control of asymptomatic patients with COVID-19 are the key issues in future epidemic prevention and recovery. In this narrative review, we summarise the existing knowledge about asymptomatic patients and put forward detection methods that are suitable for finding such patients. Besides, we compared the characteristics and transmissibility of asymptomatic patients in different populations in order to find the best screening, diagnosis and control measures for different populations. Comprehensive preventive advice is also provided to prevent the spread of infection from asymptomatic patients.

  • COVID-19
  • hospital care
  • family management
  • paediatrics
  • symptoms and symptom management

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  • YY and XY contributed equally.

  • Contributors YY, XY, DH, QY, TW and MD contributed to the material collection and manuscript writing. All authors read and approved the final manuscript.

  • Funding This work was supported by the National Natural Science Foundation of China under contract (Nos. 31672290, 31100764), the Natural Science Foundation of Hunan Province, China (No. 2016JJ3180), Open Sharing Fund for the Large-scale Instruments and Equipments of Central South University (No. CSUZC2020043), National Undergraduate Innovation Training Program of Central South University (No. S2020105330717).

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.