Clinical characteristics and clinical outcome of community clusters with SARS-CoV-2 infection

BACKGROUND: Community clustering is one of the main features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, few studies have been conducted on the clinical characteristics and clinical outcome of clustered cases and sporadic cases with COVID-19. METHODS: We recruited 41 community clusters confirmed with SARS-CoV-2 infection compared with 49 sporadic cases in Zhejiang Province from 19 January 2020 to 9 June 2020. Clinical data were collected to evaluate the clinical outcome and characteristics of community clusters. RESULTS: Compared to sporadic cases, clustered cases had significantly lower Acute Physiology and Chronic Health Evaluation II (APACHE II) score {5.0 [interquartile range (IQR), 2.0–7.5] vs. 7.0 [IQR, 4.0–12.5]; P = 0.005}, less members in intensive care unit (ICU) (6 [14.6%] vs. 18 [36.7%]; P = 0.018), and shorter time of viral shedding in fecal samples (18.5 [IQR, 17.0–28.3] vs. 32.0 [IQR, 24.3–35.5]; P = 0.002). Univariable logistic regression revealed that older age (odds ratios 1.078, 95% confidence intervals 1.007–1.154, per year increase; p = 0.032), high APACHE II score (3.171, 1.147–8.76; P = 0.026), elevated interleukin-2 levels (3.078, 1.145–8.279; P = 0.026) were associated with ICU admission of clustered cases. CONCLUSIONS: Compared to sporadic cases, clustered cases exhibited milder disease severity and a better clinical outcome, which may be closely related to the management of early detection, early diagnosis, early treatment and early isolation of COVID-19.