INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic is spreading rapidly all over the world. The Japanese government lifted the state of emergency, announced in April 2020, on May 25, but there are still sporadic clusters. Asymptomatic patients who can transmit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause some of these clusters. It is thus urgent to investigate the seroprevalence of antibodies against SARS-CoV-2 and their neutralizing activity. We conducted a cross-sectional study of >10,000 samples at hospitals in Hyogo Prefecture, Japan. METHODS: Between August 6 and October 1, 2020, we collected samples of residual blood from the patients who visited or were admitted to five hospitals and a foundation in Hyogo. We tested the samples for antibodies against SARS-CoV-2 by electrochemiluminescence immunoassay (ECLIA) and chemiluminescent enzyme immunoassay (CLEIA). Sera that were positive by ECLIA or CLEIA were analyzed by an immunochromatographic (IC) test and neutralizing activity assay. RESULTS: We tested 10,377 samples from patients aged between 0 and 99 years old; 27 cases (0.26%) were positive on the ECLIA, and 51 cases (0.49%) were positive on CLEIA. In the 14 cases that tested positive on both ECLIA and CLEIA, the positive rates on the IC test and for neutralizing activity were high (85% and 92%, respectively). In 50 cases (0.48%) that were positive by either ECLIA or CLEIA, the corresponding rates were low (20% and 6%, respectively). The positive rate of neutralizing antibody was 0.15%. CONCLUSIONS: These results indicate that most Hyogo Prefecture residents still do not have antibodies and should avoid the risk of incurring a SARS-CoV-2 infection. Two or more antibody tests should be required for seroepidemiological studies of the antibody for SARS-CoV-2, and a neutralizing activity assay is also essential.
INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic is spreading rapidly all over the world. The Japanese government lifted the state of emergency, announced in April 2020, on May 25, but there are still sporadic clusters. Asymptomatic patients who can transmit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause some of these clusters. It is thus urgent to investigate the seroprevalence of antibodies against SARS-CoV-2 and their neutralizing activity. We conducted a cross-sectional study of >10,000 samples at hospitals in Hyogo Prefecture, Japan. METHODS: Between August 6 and October 1, 2020, we collected samples of residual blood from the patients who visited or were admitted to five hospitals and a foundation in Hyogo. We tested the samples for antibodies against SARS-CoV-2 by electrochemiluminescence immunoassay (ECLIA) and chemiluminescent enzyme immunoassay (CLEIA). Sera that were positive by ECLIA or CLEIA were analyzed by an immunochromatographic (IC) test and neutralizing activity assay. RESULTS: We tested 10,377 samples from patients aged between 0 and 99 years old; 27 cases (0.26%) were positive on the ECLIA, and 51 cases (0.49%) were positive on CLEIA. In the 14 cases that tested positive on both ECLIA and CLEIA, the positive rates on the IC test and for neutralizing activity were high (85% and 92%, respectively). In 50 cases (0.48%) that were positive by either ECLIA or CLEIA, the corresponding rates were low (20% and 6%, respectively). The positive rate of neutralizing antibody was 0.15%. CONCLUSIONS: These results indicate that most Hyogo Prefecture residents still do not have antibodies and should avoid the risk of incurring a SARS-CoV-2 infection. Two or more antibody tests should be required for seroepidemiological studies of the antibody for SARS-CoV-2, and a neutralizing activity assay is also essential.
Authors: Nina Le Bert; Anthony T Tan; Kamini Kunasegaran; Christine Y L Tham; Morteza Hafezi; Adeline Chia; Melissa Hui Yen Chng; Meiyin Lin; Nicole Tan; Martin Linster; Wan Ni Chia; Mark I-Cheng Chen; Lin-Fa Wang; Eng Eong Ooi; Shirin Kalimuddin; Paul Anantharajah Tambyah; Jenny Guek-Hong Low; Yee-Joo Tan; Antonio Bertoletti Journal: Nature Date: 2020-07-15 Impact factor: 49.962
Authors: Andrew Bryan; Gregory Pepper; Mark H Wener; Susan L Fink; Chihiro Morishima; Anu Chaudhary; Keith R Jerome; Patrick C Mathias; Alexander L Greninger Journal: J Clin Microbiol Date: 2020-07-23 Impact factor: 5.948
Authors: Silvia Stringhini; Ania Wisniak; Giovanni Piumatti; Andrew S Azman; Stephen A Lauer; Hélène Baysson; David De Ridder; Dusan Petrovic; Stephanie Schrempft; Kailing Marcus; Sabine Yerly; Isabelle Arm Vernez; Olivia Keiser; Samia Hurst; Klara M Posfay-Barbe; Didier Trono; Didier Pittet; Laurent Gétaz; François Chappuis; Isabella Eckerle; Nicolas Vuilleumier; Benjamin Meyer; Antoine Flahault; Laurent Kaiser; Idris Guessous Journal: Lancet Date: 2020-06-11 Impact factor: 79.321
Authors: Margot Egger; Christian Bundschuh; Kurt Wiesinger; Christian Gabriel; Martin Clodi; Thomas Mueller; Benjamin Dieplinger Journal: Clin Chim Acta Date: 2020-05-30 Impact factor: 3.786
Authors: Kevin W Ng; Nikhil Faulkner; Georgina H Cornish; Annachiara Rosa; Ruth Harvey; Saira Hussain; Rachel Ulferts; Christopher Earl; Antoni G Wrobel; Donald J Benton; Chloe Roustan; William Bolland; Rachael Thompson; Ana Agua-Doce; Philip Hobson; Judith Heaney; Hannah Rickman; Stavroula Paraskevopoulou; Catherine F Houlihan; Kirsty Thomson; Emilie Sanchez; Gee Yen Shin; Moira J Spyer; Dhira Joshi; Nicola O'Reilly; Philip A Walker; Svend Kjaer; Andrew Riddell; Catherine Moore; Bethany R Jebson; Meredyth Wilkinson; Lucy R Marshall; Elizabeth C Rosser; Anna Radziszewska; Hannah Peckham; Coziana Ciurtin; Lucy R Wedderburn; Rupert Beale; Charles Swanton; Sonia Gandhi; Brigitta Stockinger; John McCauley; Steve J Gamblin; Laura E McCoy; Peter Cherepanov; Eleni Nastouli; George Kassiotis Journal: Science Date: 2020-11-06 Impact factor: 47.728