tetano
Editor, Senior Moderator
J Clin Virol
. 2021 Feb 18;136:104765.
doi: 10.1016/j.jcv.2021.104765. Online ahead of print.
Longitudinal follow-up of IgG anti-nucleocapsid antibodies in SARS-CoV-2 infected patients up to eight months after infection
Jan Van Elslande[SUP] 1 [/SUP], Matthijs Oyaert[SUP] 2 [/SUP], Scott Ailliet[SUP] 1 [/SUP], Marc Van Ranst[SUP] 3 [/SUP], Natalie Lorent[SUP] 4 [/SUP], Yannick Vande Weygaerde[SUP] 5 [/SUP], Emmanuel Andr?[SUP] 3 [/SUP], Katrien Lagrou[SUP] 3 [/SUP], Stien Vandendriessche[SUP] 2 [/SUP], Pieter Vermeersch[SUP] 6 [/SUP]
Affiliations
Abstract
Background: Most SARS-CoV-2 infected patients develop IgG antibodies within 2-3 weeks after symptom onset. Antibody levels have been shown to gradually decrease in the first months after infection, but few data are available at six months or later.
Methods: A retrospective multi-center study was performed using 652 samples of 236 PCR-confirmed SARS-CoV-2 infected patients from 2 Belgian University hospitals. Patients were included if at least two samples were available (range 2-7 samples); including at least one sample collected 30 days or later after first positive PCR (range 0-240 days). Of those 236 patients, 19.1 % were classified as mild/asymptomatic (mild) and 80.9 % as moderate to critical (severe). IgG anti-nucleocapsid antibodies (anti-N) were measured using the Abbott Architect immunoassay.
Results: 22.2 % of mild and 2.6 % of severe COVID-19 cases never seroconverted (p < 0.001). Of the mild patients who seroconverted 0-59 days after PCR; 18.8 %, 40.0 % and 61.1 % were seronegative in the windows 60-119 days, 120-179 days and 180-240 days after PCR, respectively. In severe patients, these numbers were 1.9 %, 10.8 % and 29.4 % respectively (p < 0.05 each). Antibody levels were significantly higher in severe patients compared to mild patients in each 60 day window (p < 0.001 each).
Conclusions: SARS-CoV-2 anti-N IgG antibody levels steadily decreased after 2 months up to 8 months post PCR. Of severe COVID-19 patients, 70.6 % remained positive up to eight months after infection. Antibody levels were significantly lower in mild SARS-CoV-2 infected patients and 61.1 % became seronegative within 6 months after the first positive PCR.
Keywords: Antibodies; COVID-19; Coronavirus; Immunoglobulin G; Longitudinal studies; SARS-CoV-2.
. 2021 Feb 18;136:104765.
doi: 10.1016/j.jcv.2021.104765. Online ahead of print.
Longitudinal follow-up of IgG anti-nucleocapsid antibodies in SARS-CoV-2 infected patients up to eight months after infection
Jan Van Elslande[SUP] 1 [/SUP], Matthijs Oyaert[SUP] 2 [/SUP], Scott Ailliet[SUP] 1 [/SUP], Marc Van Ranst[SUP] 3 [/SUP], Natalie Lorent[SUP] 4 [/SUP], Yannick Vande Weygaerde[SUP] 5 [/SUP], Emmanuel Andr?[SUP] 3 [/SUP], Katrien Lagrou[SUP] 3 [/SUP], Stien Vandendriessche[SUP] 2 [/SUP], Pieter Vermeersch[SUP] 6 [/SUP]
Affiliations
- PMID: 33636554
- PMCID: PMC7891078
- DOI: 10.1016/j.jcv.2021.104765
Abstract
Background: Most SARS-CoV-2 infected patients develop IgG antibodies within 2-3 weeks after symptom onset. Antibody levels have been shown to gradually decrease in the first months after infection, but few data are available at six months or later.
Methods: A retrospective multi-center study was performed using 652 samples of 236 PCR-confirmed SARS-CoV-2 infected patients from 2 Belgian University hospitals. Patients were included if at least two samples were available (range 2-7 samples); including at least one sample collected 30 days or later after first positive PCR (range 0-240 days). Of those 236 patients, 19.1 % were classified as mild/asymptomatic (mild) and 80.9 % as moderate to critical (severe). IgG anti-nucleocapsid antibodies (anti-N) were measured using the Abbott Architect immunoassay.
Results: 22.2 % of mild and 2.6 % of severe COVID-19 cases never seroconverted (p < 0.001). Of the mild patients who seroconverted 0-59 days after PCR; 18.8 %, 40.0 % and 61.1 % were seronegative in the windows 60-119 days, 120-179 days and 180-240 days after PCR, respectively. In severe patients, these numbers were 1.9 %, 10.8 % and 29.4 % respectively (p < 0.05 each). Antibody levels were significantly higher in severe patients compared to mild patients in each 60 day window (p < 0.001 each).
Conclusions: SARS-CoV-2 anti-N IgG antibody levels steadily decreased after 2 months up to 8 months post PCR. Of severe COVID-19 patients, 70.6 % remained positive up to eight months after infection. Antibody levels were significantly lower in mild SARS-CoV-2 infected patients and 61.1 % became seronegative within 6 months after the first positive PCR.
Keywords: Antibodies; COVID-19; Coronavirus; Immunoglobulin G; Longitudinal studies; SARS-CoV-2.