First Reported Nosocomial Outbreak of Severe Acute Respiratory Syndrome Coronavirus 2 in a Pediatric Dialysis Unit

Abstract

Background Coronavirus disease 2019 (COVID-19) is a life-threatening respiratory condition caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and was initially detected in China in December 2019. Currently, in Germany over 140,000 cases of COVID-19 are confirmed. Here we report a nosocomial outbreak of SARS-CoV-2 infections in the pediatric dialysis unit of the University Hospital of Münster (UHM). Methods Single-step real-time RT-PCR from nasopharyngeal swaps was used to diagnose the index patient and identify infected contacts. Epidemiological links were analyzed by patient interviews and chart reviews. In addition, each contact was assessed for exposure to the index case and monitored for clinical symptoms. Threshold cycle (Ct) values of all positive test results were compared between symptomatic and asymptomatic cases. Results Forty-eight cases were involved in this nosocomial outbreak. Nine contact cases developed laboratory confirmed COVID-19 infections. Two SARS-CoV-2 positive cases remained clinically asymptomatic. Eleven cases reported flu-like symptoms without positive results. Ct values were significantly lower in cases presenting typical COVID-19 symptoms, suggesting high viral shedding (p =0.007). Conclusion Person-to-person transmission was at the heart of a hospital outbreak of SARS-CoV-2 between healthcare workers (HCWs) and patients in the pediatric dialysis unit at the UHM. Semi quantitative real-time RT-PCR results suggest that individuals with high viral load pose a risk to spread SARS-CoV-2 in the hospital setting. Our epidemiological observation highlights the need to develop strategies to trace and monitor SARS-CoV-2 infected HCWs in order to prevent COVID-19 outbreaks in the hospital setting.

Clinical utility of cycle threshold values in the context of COVID-19

“…The PRISMA owchart of included studies is shown in Figure 1. Data from 18 studies were relevant for inclusion and are summarised in Tables 1 and 2. Twelve studies (63%) were conducted in China or Hong Kong, [10][11][12][13][14][15][16][17][18][19][20][21] three studies were performed in Europe [22][23][24] and three studies were carried out in the USA or Canada. [25][26][27] Nearly all studies reported data for specimens from the respiratory tract, although two studies analysed saliva, 21,22 one used stool and serum samples in addition to respiratory samples, 19 and one used both throat and anal swabs.…”

“…[12][13][14][15][16][17]22 Fourteen studies reported on the direct correlation of outcomes with Ct values. [10][11][12][13][14]16,17,20,[22][23][24][25][26][27] Three studies reported on the correlation of outcomes with viral load, determined using standard curves of Ct values versus RNA copy number, 15,19,21 and one study correlated outcomes with the inverse of Ct values, taken as a proxy for viral load. 18…”

“…Eleven studies (with numbers of PCR-positive patients ranging from 10 to 308) reported on the correlation between Ct value and disease severity, [10][11][12][13][14]16,17,20,23,25,26 ower Ct values from respiratory samples were associated with more severe disease in 7 (64%) of these ( Table 2). [11][12][13][14]16,17,23 Three studies (with numbers of PCR-positive patients ranging from 23 to 114) reported on the correlation between viral load determined via Ct values and disease severity 15,19,21 and one of these (which included 96 patients) reported that higher viral loads were signi cantly associated with more severe disease ( Table 2). 19 Of the 15 studies reporting on the correlation between Ct value or viral load determined via Ct value and disease severity, 11 were performed in hospitalised patients [10][11][12][13][14][15][16][17]19,21,23 and three included non-hospitalised patients.…”

“…[11][12][13][14]16,17,23 Three studies (with numbers of PCR-positive patients ranging from 23 to 114) reported on the correlation between viral load determined via Ct values and disease severity 15,19,21 and one of these (which included 96 patients) reported that higher viral loads were signi cantly associated with more severe disease ( Table 2). 19 Of the 15 studies reporting on the correlation between Ct value or viral load determined via Ct value and disease severity, 11 were performed in hospitalised patients [10][11][12][13][14][15][16][17]19,21,23 and three included non-hospitalised patients. 20,25,26 Of the eleven studies performed in hospitalised patients only, eight (73%) reported an association between Ct value and disease severity, [11][12][13][14]16,17,19,23 of which six showed statistical signi cance.…”

“…19 Of the 15 studies reporting on the correlation between Ct value or viral load determined via Ct value and disease severity, 11 were performed in hospitalised patients [10][11][12][13][14][15][16][17]19,21,23 and three included non-hospitalised patients. 20,25,26 Of the eleven studies performed in hospitalised patients only, eight (73%) reported an association between Ct value and disease severity, [11][12][13][14]16,17,19,23 of which six showed statistical signi cance. [12][13][14]17,19,23 None of three studies that included non-hospitalised patients reported that patients with severe disease had higher viral loads compared with those with mild disease.…”