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
Review
. 2021 Oct 29;11(11):1152.
doi: 10.3390/life11111152.

What Happens to the Immune System after Vaccination or Recovery from COVID-19?

Bruna T Tiyo  1 , Gabriela J H Schmitz  1 , Marina M Ortega  1 , Laís T da Silva  1 , Alexandre de Almeida  1 , Telma M Oshiro  1 , Alberto J da S Duarte  1
Affiliations
Review

What Happens to the Immune System after Vaccination or Recovery from COVID-19?

Bruna T Tiyo et al. Life (Basel). .

Abstract

Due to its leading role in fighting infections, the human immune system has been the focus of many studies in the context of Coronavirus disease 2019 (COVID-19). In a worldwide effort, the scientific community has transitioned from reporting about the effects of the novel coronavirus on the human body in the early days of the pandemic to exploring the body's many immunopathological and immunoprotecting properties that have improved disease treatment and enabled the development of vaccines. The aim of this review is to explain what happens to the immune system after recovery from COVID-19 and/or vaccination against SARS-CoV-2, the virus that causes the disease. We detail the way in which the immune system responds to a SARS-CoV-2 infection, including innate and adaptive measures. Then, we describe the role of vaccination, the main types of COVID-19 vaccines and how they protect us. Further, we explain the reason why immunity after COVID-19 infection plus a vaccination appears to induce a stronger response compared with virus exposure alone. Additionally, this review reports some correlates of protection from SARS-CoV-2 infection. In conclusion, we reinforce that vaccination is safe and important in achieving herd immunity.

Keywords: COVID-19; cellular response; correlates of protection; herd immunity; humoral response; recovered patients; transmission; vaccines.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

References

    1. Koenderman L., Buurman W., Daha M.R. The innate immune response. Immunol. Lett. 2014;162:95–102. doi: 10.1016/j.imlet.2014.10.010. - DOI - PubMed
    1. Trypsteen W., Van Cleemput J., Snippenberg W.V., Gerlo S., Vandekerckhove L. On the whereabouts of SARS-CoV-2 in the human body: A systematic review. PLoS Pathog. 2020;16:e1009037. doi: 10.1371/journal.ppat.1009037. - DOI - PMC - PubMed
    1. Karimzadeh S., Bhopal R., Nguyen Tien H. Review of infective dose, routes of transmission and outcome of COVID-19 caused by the SARS-COV-2: Comparison with other respiratory viruses-CORRIGENDUM. Epidemiol. Infect. 2021;149:e116. doi: 10.1017/S0950268821001084. - DOI - PMC - PubMed
    1. Sungnak W., Huang N., Bécavin C., Berg M., Queen R., Litvinukova M., Talavera-López C., Maatz H., Reichart D., Sampaziotis F., et al. SARS-CoV-2 entry factors are highly expressed in nasal epithelial cells together with innate immune genes. Nat. Med. 2020;26:681–687. doi: 10.1038/s41591-020-0868-6. - DOI - PMC - PubMed
    1. Xu H., Zhong L., Deng J., Peng J., Dan H., Zeng X., Li T., Chen Q. High expression of ACE2 receptor of 2019-nCoV on the epithelial cells of oral mucosa. Int. J. Oral Sci. 2020;12:8. doi: 10.1038/s41368-020-0074-x. - DOI - PMC - PubMed

LinkOut - more resources