Seroepidemiology of SARS-CoV-2, Yamagata, Japan, June 2020


  • Keita Morikane Yamagata University, Yamagata, Japan
  • Naohito Satoh Yamagata University, Yamagata, Japan
  • Kanji Hatano Yamagata University, Yamagata, Japan
  • Kazunori Kanouchi Yamagata University, Yamagata, Japan
  • Seiji Kakehata Yamagata University, Yamagata, Japan
  • Shinya Satoh Yamagata University, Yamagata, Japan
  • Timothy Uyeki Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
  • Yoshiyuki Ueno Yamagata University, Yamagata, Japan



We conducted a seroepidemiological study in a northern Japanese prefecture where the incidence of identified COVID-19 cases was low. In June 2020, residual sera from 1009 outpatients were tested for antibody to SARS-CoV-2 by electrochemiluminescence immunoassay.  Five specimens (0.5%) tested positive, suggesting low prevalence of SARS-CoV-2 infections in this population.

Author Biography

Keita Morikane, Yamagata University, Yamagata, Japan


Division of Clinical Laboratory and Infection Control

Yamagata University Hospital


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