Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jul 16:8:684864.
doi: 10.3389/fmed.2021.684864. eCollection 2021.

Antibodies Can Last for More Than 1 Year After SARS-CoV-2 Infection: A Follow-Up Study From Survivors of COVID-19

Kaihu Xiao  1   2 , Haiyan Yang  1   3 , Bin Liu  1 , Xiaohua Pang  2 , Jianlin Du  1 , Mengqi Liu  4 , Yajie Liu  1 , Xiaodong Jing  1 , Jing Chen  2 , Songbai Deng  1 , Zheng Zhou  5 , Jun Du  1 , Li Yin  2 , Yuling Yan  1 , Huaming Mou  2 , Qiang She  1
Affiliations

Antibodies Can Last for More Than 1 Year After SARS-CoV-2 Infection: A Follow-Up Study From Survivors of COVID-19

Kaihu Xiao et al. Front Med (Lausanne). .

Abstract

Background: COVID-19 is a global pandemic. The prevention of SARS-CoV-2 infection and the rehabilitation of survivors are currently the most urgent tasks. However, after patients with COVID-19 are discharged from the hospital, how long the antibodies persist, whether the lung lesions can be completely absorbed, and whether cardiopulmonary abnormalities exist remain unclear. Methods: A total of 56 COVID-19 survivors were followed up for 12 months, with examinations including serum virus-specific antibodies, chest CT, and cardiopulmonary exercise testing. Results: The IgG titer of the COVID-19 survivors decreased gradually, especially in the first 6 months after discharge. At 6 and 12 months after discharge, the IgG titer decreased by 68.9 and 86.0%, respectively. The IgG titer in patients with severe disease was higher than that in patients with non-severe disease at each time point, but the difference did not reach statistical significance. Among the patients, 11.8% were IgG negative up to 12 months after discharge. Chest CT scans showed that at 3 and 10 months after discharge, the lung opacity had decreased by 91.9 and 95.5%, respectively, as compared with that at admission. 10 months after discharge, 12.5% of the patients had an opacity percentage >1%, and 18.8% of patients had pulmonary fibrosis (38.5% in the severe group and 5.3% in the non-severe group, P < 0.001). Cardiopulmonary exercise testing showed that 22.9% of patients had FEV1/FVC%Pred <92%, 17.1% of patients had FEV1%Pred <80%, 20.0% of patients had a VO2 AT <14 mlO2/kg/min, and 22.9% of patients had a VE/VCO2 slope >30%. Conclusions: IgG antibodies in most patients with COVID-19 can last for at least 12 months after discharge. The IgG titers decreased significantly in the first 6 months and remained stable in the following 6 months. The lung lesions of most patients with COVID-19 can be absorbed without sequelae, and a few patients in severe condition are more likely to develop pulmonary fibrosis. Approximately one-fifth of the patients had cardiopulmonary dysfunction 6 months after discharge.

Keywords: COVID-19; SARS-CoV-2; antibody; cardiopulmonary; follow-up.

PubMed Disclaimer

Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Dynamic changes of IgG and IgM titer over time in 51 patients with COVID-19. (A) Dynamic changes of IgG levels in patients with COVID-19 after 12 months' follow-up. (B) Negative rate of IgG in COVID-19 patients at each time point with 12 months' follow-up (C) Dynamic changes of IgM levels in patients with COVID after 12 months' follow-up. (D) Negative rate of IgM in COVID-19 patients at each time point with 12 months' follow-up. T, total; NS, non-severe; S, severe.
Figure 2
Figure 2
Chest CT results. (A) The changes in the volume of opacity for each time point. (B) Volume of opacity in the severe and non-severe groups. (C) The changes in the percentage of opacity for each time point. (D) The percentage of opacity in the severe and non-severe groups. T, total; NS, non-severe; S, severe.
Figure 3
Figure 3
(A) The chest CT scan of a 79-year-old man with severe COVID-19 on admission, revealing diffuse ground-glass opacity and consolidation in the lungs. (B) Reexamination of chest CT at 10 months after discharge, showing that the ground glass opacities and consolidation had completely disappeared, and mild pulmonary fibrosis were present.
Figure 4
Figure 4
Comparison of cardiopulmonary exercise test parameters between the severe group and non-severe group. (A) Percent-predicted FVC between the two groups. (B) FEV1/FVC between the two groups. (C) Percent-predicted FEV1 between the two groups. (D) Percent-predicted MVV between the two groups. (E) Peak VO2 between the two groups. (F) VO2 AT between the two groups. (G) VE/VCO2 Slop between the two groups. (H) Percent-predicted VO2/HR between the two groups. (I) VE/VO2 ratio between the two groups. FVC, forced vital capacity; FEV1, forced expiratory volume in one second; MVV, maximal voluntary ventilation; Peak VO2, peak oxygen uptake; AT, anaerobic threshold; VE, minute ventilation; HR, heart rate; VCO2, carbon dioxide production; NS, non-severe; S, severe.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Coronavirus, Disease (COVID-19) Situation Reports,. Available online at: https://www.who.int/publications/m/item/weekly-operational-update-on-cov... (accessed June 2, 2021).
    1. Greenwood B. The contribution of vaccination to global health: past, present and future. Philos Trans R Soc London Series B Biol Sci. (2014) 369:20130433. 10.1098/rstb.2013.0433 - DOI - PMC - PubMed
    1. Tay MZ, Poh CM, Rénia L, MacAry PA, Ng LFP. The trinity of COVID-19: immunity, inflammation and intervention. Nat Rev Immunol. (2020) 20:363–74. 10.1038/s41577-020-0311-8 - DOI - PMC - PubMed
    1. Ziegler CGK, Allon SJ, Nyquist SK, Mbano IM, Miao VN, Tzouanas CN, et al. . SARS-CoV-2 Receptor ACE2 is an interferon-stimulated gene in human airway epithelial cells and is detected in specific cell subsets across tissues. Cell. (2020) 181:1016–35.e19. 10.1016/j.cell.2020.04.035 - DOI - PMC - PubMed
    1. Guzik TJ, Mohiddin SA, Dimarco A, Patel V, Savvatis K, Marelli-Berg FM, et al. . COVID-19 and the cardiovascular system: implications for risk assessment, diagnosis, and treatment options. Cardiovasc Res. (2020) 116:1666–87. 10.1093/cvr/cvaa106 - DOI - PMC - PubMed