tetano
Editor, Senior Moderator
Sci Rep
. 2021 Feb 2;11(1):2776.
doi: 10.1038/s41598-021-82428-5.
Time course of the sensitivity and specificity of anti-SARS-CoV-2 IgM and IgG antibodies for symptomatic COVID-19 in Japan
Yuki Nakano[SUP] 1 [/SUP], Makoto Kurano[SUP] 2 3 [/SUP], Yoshifumi Morita[SUP] 1 [/SUP], Takuya Shimura[SUP] 1 [/SUP], Rin Yokoyama[SUP] 1 [/SUP], Chungen Qian[SUP] 4 [/SUP], Fuzhen Xia[SUP] 5 [/SUP], Fan He[SUP] 5 [/SUP], Yoshiro Kishi[SUP] 6 [/SUP], Jun Okada[SUP] 6 [/SUP], Naoyuki Yoshikawa[SUP] 1 [/SUP], Yutaka Nagura[SUP] 7 [/SUP], Hitoshi Okazaki[SUP] 7 [/SUP], Kyoji Moriya[SUP] 8 [/SUP], Yasuyuki Seto[SUP] 9 [/SUP], Tatsuhiko Kodama[SUP] 10 [/SUP], Yutaka Yatomi[SUP] 11 12 [/SUP]
Affiliations
Abstract
The accurate and prompt diagnosis of SARS-CoV-2 infection is required for the control and treatment of the coronavirus infection disease 2019 (COVID-19). In this study, we aimed to investigate the time courses of the anti-severe acute corona respiratory syndrome coronavirus 2 (SARS-CoV-2) IgM and IgG titers and to evaluate the sensitivity and specificity of such tests according to the specific day after the onset of COVID-19 among a patient population in Japan. We measured the titers of SARS-CoV-2 IgM and IgG in sera from 105 subjects, including 26 symptomatic COVID-19 patients, using chemiluminescent immunoassay (CLIA) methods utilizing magnetic beads coated with SARS-CoV-2 nucleocapsid protein and spike protein. The results of a ROC analysis suggested the possibility that the cutoff values in Japan might be lower than the manufacturer's reported cutoff (10 AU/mL): 1 AU/mL for IgM and 5 AU/mL for IgG. The sensitivity of the test before Day 8 after symptom onset was less than 50%; at Days 9-10, however, we obtained a much higher sensitivity of 81.8% for both IgM and IgG. At 15 days or later after symptom onset, the SARS-CoV-2 IgG test had a sensitivity of 100%. These results suggest that if the number of days since disease onset is taken into consideration, these antibody tests could be very useful for the diagnosis of COVID-19 and similar diseases.
. 2021 Feb 2;11(1):2776.
doi: 10.1038/s41598-021-82428-5.
Time course of the sensitivity and specificity of anti-SARS-CoV-2 IgM and IgG antibodies for symptomatic COVID-19 in Japan
Yuki Nakano[SUP] 1 [/SUP], Makoto Kurano[SUP] 2 3 [/SUP], Yoshifumi Morita[SUP] 1 [/SUP], Takuya Shimura[SUP] 1 [/SUP], Rin Yokoyama[SUP] 1 [/SUP], Chungen Qian[SUP] 4 [/SUP], Fuzhen Xia[SUP] 5 [/SUP], Fan He[SUP] 5 [/SUP], Yoshiro Kishi[SUP] 6 [/SUP], Jun Okada[SUP] 6 [/SUP], Naoyuki Yoshikawa[SUP] 1 [/SUP], Yutaka Nagura[SUP] 7 [/SUP], Hitoshi Okazaki[SUP] 7 [/SUP], Kyoji Moriya[SUP] 8 [/SUP], Yasuyuki Seto[SUP] 9 [/SUP], Tatsuhiko Kodama[SUP] 10 [/SUP], Yutaka Yatomi[SUP] 11 12 [/SUP]
Affiliations
- PMID: 33531605
- DOI: 10.1038/s41598-021-82428-5
Abstract
The accurate and prompt diagnosis of SARS-CoV-2 infection is required for the control and treatment of the coronavirus infection disease 2019 (COVID-19). In this study, we aimed to investigate the time courses of the anti-severe acute corona respiratory syndrome coronavirus 2 (SARS-CoV-2) IgM and IgG titers and to evaluate the sensitivity and specificity of such tests according to the specific day after the onset of COVID-19 among a patient population in Japan. We measured the titers of SARS-CoV-2 IgM and IgG in sera from 105 subjects, including 26 symptomatic COVID-19 patients, using chemiluminescent immunoassay (CLIA) methods utilizing magnetic beads coated with SARS-CoV-2 nucleocapsid protein and spike protein. The results of a ROC analysis suggested the possibility that the cutoff values in Japan might be lower than the manufacturer's reported cutoff (10 AU/mL): 1 AU/mL for IgM and 5 AU/mL for IgG. The sensitivity of the test before Day 8 after symptom onset was less than 50%; at Days 9-10, however, we obtained a much higher sensitivity of 81.8% for both IgM and IgG. At 15 days or later after symptom onset, the SARS-CoV-2 IgG test had a sensitivity of 100%. These results suggest that if the number of days since disease onset is taken into consideration, these antibody tests could be very useful for the diagnosis of COVID-19 and similar diseases.