Underperformance of Reverse-Transcriptase Polymerase Chain Reaction in Japan and Potential Implications From Diamond Princess Cruise Ship and Other Countries During the Ongoing COVID-19 Pandemic

Document Type: Letter to Editor


1 Department of Reproductive, Developmental and Aging Sciences, Graduate School of Medicine, University of Tokyo, Tokyo, Japan

2 Medical Governance Research Institute, Tokyo, Japan

3 Department of Breast Surgery, Jyoban Hospital of Tokiwa Foundation, Fukushima, Japan

4 Department of Surgery, Sendai City Medical Center, Miyagi, Japan

5 Tribhuvan University Institute of Medicine, Kathmandu, Nepal

6 School of Public Health, Fudan University, Shanghai, China


Main Subjects


Dear Editor,

The coronavirus disease 2019 (COVID-19) emerged in Wuhan, Hubei province, China, in November 2019, and spread to multiple countries, leading the World Health Organization (WHO) to declare it a pandemic on March 11, 2020. As of June 20, 2020, 8 766 887 cases and 462 706 deaths had been reported, with a case fatality rate (CFR) of 5.3% worldwide.1 While a crude CFR of COVID-19 in Japan was reportedly similar at 5.3% on June 20, 2020,1 the CFR reported from different regions of the world vary widely, partly due to differences in the healthcare capacity and thoroughness of the crisis response and extent and progress of the epidemic.2 ... (Read more...)


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