Volume 102, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645

There is no abstract available for this article.

[open-access] This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Article metrics loading...

The graphs shown below represent data from March 2017
Loading full text...

Full text loading...



  1. Bai Y, Yao L, Wei T, Tian F, Jin DY, Chen L, Wang M, 2020. Presumed asymptomatic carrier transmission of COVID-19. JAMA 323: 14061407.
    [Google Scholar]
  2. Pan X, Chen D, Xia Y, Wu X, Li T, Ou X, Zhou L, Liu J, 2020. Asymptomatic cases in a family cluster with SARS-CoV-2 infection. Lancet Infect Dis 20: 410411.
    [Google Scholar]
  3. Kimball A et al., 2020. Asymptomatic and presymptomatic SARS-CoV-2 infections in residents of a long-term care skilled nursing facility–King county, Washington, March 2020. MMWR Morb Mortal Wkly Rep 69: 377381.
    [Google Scholar]
  4. Rothe C et al., 2020. Transmission of 2019-nCoV infection from an asymptomatic contact in Germany. N Engl J Med 382: 970971.
    [Google Scholar]
  5. Wei WELZ, Chiew CJ, Yong SE, Toh MP, Lee VJ, 2020. Presymptomatic transmission of SARS-CoV-2–Singapore, January 23–March 16, 2020. MMWR Morb Mortal Wkly Rep 69: 411415.
    [Google Scholar]
  6. Zou L et al., 2020. SARS-CoV-2 viral load in upper respiratory specimens of infected patients. N Engl J Med 382: 11771179.
    [Google Scholar]
  7. Li R, Pei S, Chen B, Song Y, Zhang T, Yang W, Shaman J, 2020. Substantial undocumented infection facilitates the rapid dissemination of novel coronavirus (SARS-CoV2). Science. Available at: https://doi.org/10.1126/science.abb3221.
    [Google Scholar]
  8. Moriarty LF et al., 2020. Public health responses to COVID-19 outbreaks on cruise ships — worldwide, February–March 2020. MMWR Morb Mortal Wkly Rep 69: 347352.
    [Google Scholar]
  9. Leung CC, Lam TH, Cheng KK, 2020. Mass masking in the COVID-19 epidemic: people need guidance. Lancet 395: 945.
    [Google Scholar]
  10. [Google Scholar]
  11. CDC, 2020. Recommendation Regarding the Use of Cloth Face Coverings, Especially in Areas of Significant Community-Based Transmission, 2020. Available at: https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/cloth-face-cover.html. Accessed April 15, 2020.
    [Google Scholar]
  12. Klompas M, Morris CA, Sinclair J, Pearson M, Shenoy ES, 2020. Universal masking in hospitals in the covid-19 era. N Engl J Med. Available at: https://doi.org/10.1056/NEJMp2006372.
    [Google Scholar]
  13. Brainard JS, Jones N, Lake I, Hooper L, Hunter P, 2020. Facemasks and similar barriers to prevent respiratory illness such as covid-19: a rapid systematic review. medRxiv. Available at: https://doi.org/10.1101/2020.04.01.20049528.
    [Google Scholar]
  14. Leung NHL et al., 2020. Respiratory virus shedding in exhaled breath and efficacy of face masks. Nat Med. Available at: https://doi.org/10.1038/s41591-020-0843-2.
    [Google Scholar]
  15. Papineni RS, Rosenthal FS, 1997. The size distribution of droplets in the exhaled breath of healthy human subjects. J Aerosol Med 10: 105116.
    [Google Scholar]
  16. MacIntyre CR et al., 2015. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ Open 5: e006577.
    [Google Scholar]
  17. Howard J et al., 2020. Face masks against COVID-19: an evidence review. Preprints. Available at: https://www.preprints.org/manuscript/202004.0203/v1.
    [Google Scholar]
  • Received : 10 Apr 2020
  • Accepted : 16 Apr 2020
  • Published online : 22 Apr 2020
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error