Eosinophil responses during COVID-19 infections and coronavirus vaccination

J Allergy Clin Immunol. 2020 Jul;146(1):1-7. doi: 10.1016/j.jaci.2020.04.021. Epub 2020 Apr 25.


Eosinophils are circulating and tissue-resident leukocytes that have potent proinflammatory effects in a number of diseases. Recently, eosinophils have been shown to have various other functions, including immunoregulation and antiviral activity. Eosinophil levels vary dramatically in a number of clinical settings, especially following eosinophil-targeted therapy, which is now available to selectively deplete these cells. There are key coronavirus disease 2019 (COVID-19)-related questions concerning eosinophils whose answers affect recommended prevention and care. First, do patients with eosinophilia-associated diseases have an altered course of COVID-19? Second, do patients with eosinopenia (now intentionally induced by biological drugs) have unique COVID-19 susceptibility and/or disease course? This is a particularly relevant question because eosinopenia is associated with acute respiratory deterioration during infection with the severe acute respiratory syndrome coronavirus 2, the causative agent of COVID-19. Third, do eosinophils contribute to the lung pathology induced during COVID-19 and will they contribute to immunopotentiation potentially associated with emerging COVID-19 vaccines? Herein, we address these timely questions and project considerations during the emerging COVID-19 pandemic.

Keywords: COVID-19; Coronavirus; SARS; eosinophils; immunopathology; immunopotentiation; vaccines.

Publication types

  • Review

MeSH terms

  • Animals
  • Betacoronavirus / immunology*
  • COVID-19
  • COVID-19 Vaccines
  • Coronavirus Infections / immunology*
  • Coronavirus Infections / prevention & control*
  • Eosinophils / immunology*
  • Humans
  • Pandemics / prevention & control*
  • Pneumonia, Viral / immunology*
  • Pneumonia, Viral / prevention & control*
  • SARS-CoV-2
  • Viral Vaccines / immunology*


  • COVID-19 Vaccines
  • Viral Vaccines