Surveillance testing reveals a significant proportion of hospitalized patients with SARS-CoV-2 are asymptomatic

Abstract

Background: The proportion of positive patients admitted to acute-care hospitals for reasons other than coronavirus disease-19 (COVID-19) is unknown. These patients potentially put other patients and healthcare workers at risk of infection. Objective: The objective of this study was to define the proportion of asymptomatic patients admitted with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Secondary objectives were to define the positivity rate, reasons for admission, and the geographic distribution in the region. Methods: Universal surveillance testing for SARS-CoV-2 was performed on patients admitted to this hospital over a 12-week period from April 9, 2020 to July 1, 2020. Positive patients were categorized as either symptomatic or asymptomatic as defined by the 11 criteria per the Centers for Disease Control and Prevention. The positivity rate, proportion with and without symptoms, reasons for admission, and geographic distribution in the region were recorded. Results: The positivity rate ranged from 0.8% to 6.2%. The proportion of asymptomatic patients with SARS-CoV-2 was 37%. Asymptomatic patients primarily presented to the hospital because of either trauma or labor. Some clusters in the region were identified of both symptomatic and asymptomatic patients. Conclusions: The proportion of asymptomatic patients admitted with SARS-CoV-2 was significant. Identifying and isolating asymptomatic patients likely prevented exposure and development of hospital-acquired COVID-19 cases among healthcare workers and other patients, supporting the universal surveillance of all admitted patients.

Global Percentage of Asymptomatic SARS-CoV-2 Infections Among the Tested Population and Individuals With Confirmed COVID-19 Diagnosis

“…Of these, 282 studies underwent full-text review. Ninety-five studies with information concerning the percentage of asymptomatic infections among the tested and confirmed populations were included in the final analysis 12 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , …”

“…Among 95 studies, 18 were excluded because that the percentage of asymptomatic infections among the confirmed population was 100%. 22 , 30 , 31 , 36 , 39 , 43 , 49 , 56 , 58 , 71 , 77 , 79 , 80 , 81 , 87 , 96 , 101 , 108 The remaining 77 studies were included in the meta-analysis for the percentage of asymptomatic infections among the confirmed population, 12 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 32 , 33 , 34 , 35 , 37 , 38 , 40 , 41 , 42 , 44 , 45 , 46 , 47 , 48 , 50 , 51 , 52 , 53 , 54 , 55 , 57 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 <...>…”

Asymptomatic RT-PCR positive COVID-19 patients in orthopaedic pre-operative evaluation during the peak of the second wave

“…( Jin et al, 2020 , Haitao et al, 2020 ) A surveillance testing of hospitalized patients for SARS-CoV-2 from Louisville, Kentucky, USA found 76% of female gender among the asymptomatic cases. ( Arnold et al, 2021 )…”

“…This means patients are being infected while staying at the hospital. A surveillance study of hospitalized trauma and labor patients revealed a gradual increase in the rate of SARS-CoV-2 infection from 20% to 70% during their stay in the hospital ( Arnold et al, 2021 ). According to another study from Italy, the incidence of SARS-CoV-2 hospital-acquired infection is 12–15%.…”

Use of serial testing to interrupt a severe acute respiratory coronavirus virus 2 (SARS-CoV-2) outbreak on a hospital medical floor—Minnesota, October–December 2020

“…2,33 SARS-CoV-2 breakthrough infections can occur in vaccinated HCP and patients making it still important to implement protocols that allow for detection of infectious individuals without relying on the presence of symptoms or contact tracing alone. Coupled with preventive measures such as PPE use, serial testing could help detect and prevent transmission within healthcare facilities in outbreak situations or with suspected nosocomial transmission.…”