Factors associated with prolonged viral detection in asymptomatic and mildly symptomatic patients with SARS-CoV-2 infection.

INTRODUCTION: Data on the clinical course and duration of viral RNA detection in patients with mild or asymptomatic coronavirus disease 2019 are limited. METHODOLOGY: In this retrospective analysis, clinical characteristics and serial real-time reverse transcriptase-polymerase chain reaction (RT-PCR) results were reviewed in a cohort of 1186 asymptomatic and mildly symptomatic coronavirus disease 2019 patients in South Korea. Factors associated with prolonged duration of RT-PCR positivity for severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) were also evaluated. Patients with two consecutive negative RT-PCR tests ≥ 24 hours apart were considered to be in virologic remission and discharged. RESULTS: The average virologic remission period, defined as the number of days from diagnosis to virologic remission, was 22.0 ± 9.7 days; patients with longer than 30 days accounted for 21.2% (251/1186) of the population. Patients who took longer than 30 days to achieve virologic remission had a higher frequency of overall symptoms (p < 0.001) and respiratory symptoms (p < 0.001). In multivariate analysis using Cox-proportional hazard regression, it was confirmed that respiratory symptoms (hazard ratio [HR], 0.7372; 95% confidence interval [CI], 0.6540-0.8311) and gastrointestinal symptoms (HR, 0.8213; 95% CI, 0.6970-0.9679) were independent factors associated with prolonged virologic remission. Age and co-morbidity such as diabetes and hypertension were not associated with the prolonged RT-PCR positivity. CONCLUSIONS: A considerable percentage of asymptomatic and mildly symptomatic patients with coronavirus disease 2019 showed prolonged RT-PCR positivity for SARS-CoV-2; which was independently associated with the presence of symptoms, but not with age and co-morbidity.

Survival Analysis of Treatment Efficacy in Comparative Coronavirus Disease 2019 Studies.

For survival analysis in comparative coronavirus disease 2019 trials, the routinely used hazard ratio may not provide a meaningful summary of the treatment effect. The mean survival time difference/ratio is an intuitive, assumption-free alternative. However, for short-term studies, landmark mortality rate differences/ratios are more clinically relevant and should be formally analyzed and reported.

Recovery from Coronavirus Disease 2019 among Older Adults in Post-Acute Skilled Nursing Facilities.

OBJECTIVES: To examine functional outcomes of post-acute care for coronavirus disease 2019 (COVID-19) in skilled nursing facilities (SNFs). DESIGN: Retrospective cohort. SETTING AND PARTICIPANTS: Seventy-three community-dwelling adults ≥65 years of age admitted for post-acute care from 2 SNFs from March 15, 2020, to May 30, 2020. MEASURE(S): COVID-19 status was determined from chart review. Frailty was measured with a deficit accumulation frailty index (FI), categorized into nonfrail, mild frailty, and moderate-to-severe frailty. The primary outcome was community discharge. Secondary outcomes included change in functional status from SNF admission to discharge, based on modified Barthel index (mBI) and continuous functional scale scored by physical (PT) and occupational therapists (OT). RESULTS: Among 73 admissions (31 COVID-19 negative, 42 COVID-19 positive), mean [standard deviation (SD)] age was 83.5 (8.8) and 42 (57.5%) were female, with mean FI of 0.31 (0.01) with no differences by COVID-19 status. The mean length of SNF stay for rehabilitation was 21.2 days (SD 11.1) for COVID-19 negative with 20 (64.5%) patients discharged to community, compared to 23.0 (SD 12.2) and 31 (73.8%) among patients who tested positive for COVID-19. Among those discharged to the community, all groups improved in mBI, PT, and OT score. Those with moderate-to-severe frailty (FI >0.35) had lower mBI scores on discharge [92.0 (6.7) not frail, 81.0 (15.4) mild frailty, 48.6 (20.4) moderate-to-severe frailty; P = .002], lower PT scores on discharge [54.2 (3.9) nonfrail, 51.5 (8.0) mild frailty, 37.1 (9.7) moderate-to-severe frailty; P = .002], and lower OT score on discharge [52.9 (3.2) nonfrail, 45.8 (9.4) mild frailty, 32.4 (7.4) moderate or worse frailty; P = .001]. CONCLUSIONS AND IMPLICATIONS: Older adults admitted to a SNF for post-acute care with COVID-19 had community discharge rates and functional improvement comparable to a COVID-19 negative group. However, those who are frailer at admission tended to have lower function at discharge.

Epidemiological and clinical characteristics of coronavirus disease 2019 in Daegu, South Korea.

OBJECTIVES: Two Coronavirus Disease 2019 (COVID-19) outbreaks simultaneously occurred at a church and a long-term care facility in Daegu, South Korea. This study aimed to investigate the epidemiological characteristics of COVID-19 and factors related to severe outcomes. METHODS: We enrolled all inpatients diagnosed with COVID-19 between February 21 and April 2, 2020, in Daegu Dongsan Hospital. We analyzed their clinical and demographic data, laboratory parameters, radiological findings, symptoms, and treatment outcomes. RESULTS: Of 694 patients, severe cases accounted for 19.7% (137 patients). No severe case was observed among patients aged ≤19 years. Hypertension was the most common comorbidity (27%), and cough was the most common symptom (59%). Asymptomatic patients accounted for 14.4% of cases. Lymphopenia, lactate dehydrogenase, C-reactive protein, and albumin were associated with severe outcomes. The first outbreak was mostly associated with younger age groups, and asymptomatic patients mostly showed mild progression. In the second outbreak involving a long-term care facility, both the number of severe patients and the mortality rate were higher. CONCLUSIONS: The overall mortality in Daegu was low, which might have resulted from large scale mass screening to detect patients and starting appropriate treatment, including hospitalization for severe cases, and quarantine for asymptomatic patients.

How to Quantify and Interpret Treatment Effects in Comparative Clinical Studies of COVID-19.

Clinical trials of treatments for coronavirus disease 2019 (COVID-19) draw intense public attention. More than ever, valid, transparent, and intuitive summaries of the treatment effects, including efficacy and harm, are needed. In recently published and ongoing randomized comparative trials evaluating treatments for COVID-19, time to a positive outcome, such as recovery or improvement, has repeatedly been used as either the primary or key secondary end point. Because patients may die before recovery or improvement, data analysis of this end point faces a competing risk problem. Commonly used survival analysis techniques, such as the Kaplan-Meier method, often are not appropriate for such situations. Moreover, almost all trials have quantified treatment effects by using the hazard ratio, which is difficult to interpret for a positive event, especially in the presence of competing risks. Using 2 recent trials evaluating treatments (remdesivir and convalescent plasma) for COVID-19 as examples, a valid, well-established yet underused procedure is presented for estimating the cumulative recovery or improvement rate curve across the study period. Furthermore, an intuitive and clinically interpretable summary of treatment efficacy based on this curve is also proposed. Clinical investigators are encouraged to consider applying these methods for quantifying treatment effects in future studies of COVID-19.

Diagnosis of Coronavirus Disease 2019

The first massive outbreak of coronavirus disease 2019 (COVID-19) in Korea was controlled by fast diagnosis, isolation and triage systems. The development of therapeutic agents and vaccinations are going on, but many studies clarified the nature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this review, we will discuss the characteristics and spreading of SARS-CoV-2, and prognostic factors and diagnosis of COVID-19.