Sick time

See allHide authors and affiliations

Science  20 Mar 2020:
Vol. 367, Issue 6484, pp. 1294-1297
DOI: 10.1126/science.367.6484.1294

eLetters is an online forum for ongoing peer review. Submission of eLetters are open to all. eLetters are not edited, proofread, or indexed.  Please read our Terms of Service before submitting your own eLetter.

Compose eLetter

Plain text

  • Plain text
    No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Author Information
First or given name, e.g. 'Peter'.
Your last, or family, name, e.g. 'MacMoody'.
Your email address, e.g. higgs-boson@gmail.com
Your role and/or occupation, e.g. 'Orthopedic Surgeon'.
Your organization or institution (if applicable), e.g. 'Royal Free Hospital'.
Statement of Competing Interests

This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

Enter the characters shown in the image.

Vertical Tabs

  • RE: Winter is gone, but ‘sick time’ is not over
    • Roberto Manfredini, Full professor, MD, PhD, Internist,, University of Ferrara & Azienda Ospedaliero-Universitaria S.Anna, Ferrara, Italy
    • Other Contributors:
      • Alfredo De Giorgi, MD, Internist, Azienda Ospedaliero-Universitaria S.Anna, Ferrara, Italy
      • Fabio Fabbian, Associate professor, MD, PhD, Internist, University of Ferrara & Azienda Ospedaliero-Universitaria S.Anna, Ferrara, Italy

    Different diseases have different patterns (1), and quoting with Hippocrates ‘Whoever wishes to investigate medicine properly, should proceed thus: in the first place to consider the seasons of the year, and what effects each of them produces for they are not at all alike, but differ much from themselves in regard to their changes’ (2). Coronavirus disease (COVID-19), first reported last December in Wuhan, China, rapidly spread worldwide and caused ~900,000 confirmed infections and ~44,000 deaths (as of 1 April 2020). Italy, with ~113,000/13,000, respectively, ranks second in the world, with Lombardy and Emilia-Romagna as most affected regions (>45,000/>7,500, and >15,000/>1,700, respectively).

    On one hand, winter is characterized by stressful conditions for the organism. Shorter days have been shown to predict significant upregulation of immune function, eg, natural killer cell cytotoxicity, peripheral blood mononuclear cell proliferation, and interleukin-6 (IL-6) plasma levels (3). Moreover, winter is characterized by higher air pollution levels, frequently associated with increased total hospital admissions, whose an excessive estimated risk of ~3.5. In particular, PM2.5 was associated with an increased risk of 1.5 to 2 and 1.1 to 1.8 for cardiovascular and respiratory admissions, respectively (4). Moreover, harmful effects of PM2.5 do not only depend on air concentrations, but also on seasonal changes. In fact, the cytotoxicity of winter PM2.5 (wPM2...

    Show More
    Competing Interests: None declared.

Stay Connected to Science

Editor's Blog

Navigate This Article