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Soaring Asymptomatic Infected Individuals Bring About Barriers and Difficulties for Interruption of COVID-19

Muxin Chen1,2, Lin Ai2,3, Dana Huang1

  • 1Institute of Pathogenic Biology, Shenzhen Center for Disease Control and Prevention, Shenzhen, China.

Vector Borne and Zoonotic Diseases (Larchmont, N.Y.)
|August 10, 2021
PubMed

Insights

The proportion of asymptomatic COVID-19 infections is rising, particularly among imported cases. Early detection of asymptomatic carriers is crucial for controlling the global pandemic.

Area of Science:

  • Epidemiology
  • Infectious Diseases
  • Public Health

Background:

  • Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, has led to a global pandemic with significant health and economic impacts.
  • Identifying asymptomatic carriers is vital for effective disease control and prevention strategies.

Purpose of the Study:

  • To identify and analyze asymptomatic SARS-CoV-2 infected individuals in Shenzhen, China.
  • To provide data supporting the development of control measures to curb COVID-19 spread.

Main Methods:

  • A retrospective observational multicenter study.
  • Analysis of medical records from 462 confirmed COVID-19 patients and 45 asymptomatic infected individuals in Shenzhen.
  • Data collected from January 19 to April 30, 2020.

Main Results:

  • A total of 462 confirmed COVID-19 cases were identified, with 91.56% being domestic and 8.44% imported.
  • Among 45 asymptomatic infections, 68.89% were local and 31.11% were imported.
  • The proportion of asymptomatic infections is increasing (p < 0.0001), with higher rates in imported cases compared to domestic ones (OR=4.90, p < 0.0001).

Conclusions:

  • The increasing prevalence of asymptomatic SARS-CoV-2 infections necessitates enhanced surveillance.
  • Developing sensitive and specific diagnostic methods is critical for controlling the COVID-19 pandemic.
  • Targeted strategies for imported cases may be required to mitigate transmission.

Keywords:
COVID-19ChinaSARS-CoV-2asymptomatic infectionpathogen carriertransmission in incubation period

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