Nymisha L Boddeti1, Ivan Berezowski2, Dania Taylor3, Dhruvil Prajapati4, Jigar Patel5. 1. International Medicine Program, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States. Electronic address: nboddeti@gwu.edu. 2. International Medicine Program, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States. Electronic address: iberezowski@gwu.edu. 3. International Medicine Program, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States. Electronic address: daniataylor@gwu.edu. 4. International Medicine Program, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States. Electronic address: dprajapati@gwu.edu. 5. International Medicine Program, The George Washington University School of Medicine and Health Sciences, Washington, DC, United States. Electronic address: jigar.r.patel@outlook.com.
To the Editor,We read with great interest the recent article by Wee et. al. (Wee et al., 2021), which explores the use of rapid-antigen detection (RAD) testing in asymptomatic hospital visitor screening. It certainly adds depth to the current literature, and we would like to share some comments.The authors assessed the utility of RAD testing for SARS-CoV-2 among visitors to a large hospital campus in Singapore over an 8-week period in a low-incidence setting. We believe that the term “low-incidence” requires further clarification whether it was defined on the basis of the World Health Organization (WHO)’s level of community transmission (WHO, 2020), the Centers for Disease Control and Prevention (CDC)’s definition (CDC, 2020), or the hospital's emergency department admissions. It would be beneficial to mention the baseline incidence of COVID-19 infection and vaccine availability at the time of the study. It would also be a worthwhile inclusion to mention the fact that the BD Veritor antigen rapid-test-kit requires 2 separate tests to be taken 24-48 hours apart (U.S. Food & Drug Administration, 2021) as well as the definition of a negative test result—specifically, whether only 1 or both tests taken 24-48 hours apart must be negative.Because the inclusion criterion only required visitors who "intended" to visit for ≥30 minutes to receive RAD testing, we are uncertain if visitors who declared a short visit but then overstayed, that is, case 2 in Table 1 (in Wee et al., 2021), were also included in the study. The reasons behind only 82.4% of visitors who stayed ≥30 minutes receiving RAD testing needs more clarification. We believe that a CONSORT (Consolidated Standards of Reporting Trials) flow diagram would be useful to display the number and allocation of participants as well as any exclusion criteria contributing to the RAD testing rate.The participants' baseline characteristics such as age, sex, and comorbidities could be included in Table 1 to describe the studied population. In addition, the title of Table 1 requires clarification, as it indicates that the data were obtained over a 6-week period, although the actual study took place over an 8-week period. It would also be helpful to clarify how it includes a total number of 6 cases despite only 5 visitors having positive RAD testing according to the automated-visitor-management-systems data. Case 6 appears to have been derived from the national digital and retrospective contact tracing, but it is unclear whether the caregiver of the patient underwent RAD testing at each visit before the third.
Disclosures
Boddeti N, Berezowski I, Taylor D, Prajapati D, and Patel J declare that they have no financial interest or relationship to disclose regarding this letter to the editor.
Funding
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Compliance with Ethics Guidelines
This article is based on previously conducted studies and does not contain any new studies with human participants or animals performed by any of the authors.