COVID-19 Cases Detection: Suspect Case Strategy

Zhongliang Ji, Kailin Lu, Xuedong Sun


Background and objective: as COVID-19 has triggered enormous human casualties and disastrous economic loss, the strategies to contain its spread are urgently needed. We aim to assess the value of our suspect case strategy on COVID-19 cases detection and ensure it to be a complement to the RT-PCR test. Materials and methods: from January 23 to April 30, 2020, patients admitted to our emergence isolation ward (EIW) were analyzed in this study. With RT-PCR as a reference standard, all participants were assigned to COVID-19 positive and negative groups. We compared the performance of the suspect case strategy, WBC, LYM, and chest radiography on COVID-19 detection. Results: one hundred twenty-five cases were analyzed in the study period. The receiver operating characteristic (ROC) curve revealed the sensitivity of WBC and LYM on COVID-19 detection was 92.11% and 76.31%, respectively. The sensitivity of the suspect case was 94.73%, and the sensitivity of chest CT was 53.33%. Statistically significant differences were observed for the suspect case, WBCs, LYM, and chest CT on COVID-19 detection. Discussion: suspect case strategy can help identify false negative RT-PCR tests and be a useful complement to RT-PCR in some countries with a tremendous shortage of RT-PCR agents and specialized laboratory during the COVID-19 outbreak.


Suspect Case; COVID-19; RT-PCR; Blood Test; Chest CT

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