Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Mar 20;21(1):551.
doi: 10.1186/s12889-021-10548-8.

Study on the COVID-19 infection status, prevention and control strategies among people entering Shenzhen

Xuan Zou #  1 , Zi-Qian Xu #  1 , Hai-Rui Wang  1 , Bi-Xin Wang  1 , Jian-Fan He  1   2 , Jing-Zhong Wang  3
Affiliations

Study on the COVID-19 infection status, prevention and control strategies among people entering Shenzhen

Xuan Zou et al. BMC Public Health. .

Erratum in

Abstract

Background: The novel coronavirus disease 2019 (COVID-19) confirmed cases overseas have continued to rise in the last months, and many people overseas have chosen to return to China. This increases the risk of a large number of imported cases which may cause a relapse of the COVID-19 outbreak. In order to prevent imported infection, the Shenzhen government has implemented a closed-loop management strategy using nucleic acid testing (NAT) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and requiring 14 days of medical observation for individuals with an overseas tour history (Hong Kong, Macao, Taiwan province and other countries). Our study aims to describe the status of COVID-19 infection among people entering Shenzhen, and to evaluate the effect of the closed-loop management strategy.

Methods: We undertook a descriptive study and risk analysis by the entry time, time of reporting, and local confirmed cases in countries of origin. The NAT were completed in Shenzhen Center for Disease Control and Prevention (CDC), ten district-level CDCs, and fever clinics.

Results: A total of 86,844 people from overseas entered Shenzhen from January 1 to April 18, 2020; there were 39 imported COVID cases and 293 close contacts. The infection rate of people entering was 4.49‰ [95% Confidence interval (CI): 3.26‰-6.05‰]. Fourteen imported cases (35.9%) came from the UK, and nine (23.08%) came from the USA. People entering from the USA since March 9 or from the UK since March 13 are the high-risk population. As of July 17, there have been no new confirmed cases in Shenzhen for 153 days, and the numbers of confirmed case, close contacts, and asymptomatic cases are 0.

Conclusions: The closed-loop management has been effective in preventing imported infection and controlling domestic relapse. The distribution of entry time and report time for imported cases overseas was similar. This shows that it is important to implement closed-loop management at the port of entry.

Keywords: COVID-19; Closed-loop management; Imported cases; Prevention and control; SARS-CoV-2.

PubMed Disclaimer

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Flowchart of the closed-loop management system in Shenzhen
Fig. 2
Fig. 2
The distribution of all people entering Shenzhen
Fig. 3
Fig. 3
The top 10 countries of origin based on the number of people entering
Fig. 4
Fig. 4
a Importation risk map (from January 3 to April 18). b Importation risk (From January 3 to April 18)
Fig. 5
Fig. 5
The daily number of people entering from the US (from January 3 to April 18) and new local confirmed cases in the US (from March 1 to April 18)
Fig. 6
Fig. 6
The daily number of people entering from the UK (from February 28 to April 18) and new local confirmed cases in the UK (from March 1 to April 18)
Fig. 7
Fig. 7
The distribution of imported cases in Shenzhen
Fig. 8
Fig. 8
The countries of origin of imported cases
Fig. 9
Fig. 9
New confirmed cases in Shenzhen
Fig. 10
Fig. 10
The entry and report time of imported cases in Shenzhen
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. WHO . Novel coronavirus (2019-NCoV) situation report 1. Geneva: World Health Organization; 2020.
    1. Li Q, Guan X, Wu P, et al. Early transmission dynamics in Wuhan, China, of novel coronavirus-infected pneumonia. N Engl J Med. 2020;382(13):1199–1207. doi: 10.1056/NEJMoa2001316. - DOI - PMC - PubMed
    1. Chen N, Zhou M, Dong X, et al. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. Lancet. 2020;395:507–513. doi: 10.1016/S0140-6736(20)30211-7. - DOI - PMC - PubMed
    1. Wang D, Hu B, Hu C, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China. JAMA. 2020;323:1061–1069. doi: 10.1001/jama.2020.1585. - DOI - PMC - PubMed
    1. Minodier L, Charrel RN, Ceccaldi PE, et al. Prevalence of gastrointestinal symptoms in patients with influenza, clinical significance, and pathophysiology of human influenza viruses in faecal samples: what do we know? Virol J. 2015;12:215. doi: 10.1186/s12985-015-0448-4. - DOI - PMC - PubMed

MeSH terms