A key question about pneumonia and influenza is the role of sunlight and vitamin-D production on the incidence, severity, and mortality rates from the diseases. Pneumonia and influenza cases and deaths are seasonal, peaking in the winter when sunlight levels and temperatures are lower. The curve for pneumonia and influenza deaths is roughly sinusoidal, which would be expected from something connected to sunlight levels. This is not what one would naively expect from children spreading the disease during the school year; we would expect an abrupt step up in the fall when kids return to school and a step down in the spring when school closes.
The body needs sunlight to produce vitamin D. Sunlight, particularly the ultraviolet component, can damage or kill viruses and bacteria. These and other effects related to sunlight levels may play a role in the sinusoidal pattern of pneumonia and influenza deaths.
Popular Sources
“Want to Protect Yourself From Getting the Flu? Get Some Sunshine” by Jamie Ducharme, Time, March 2, 2018 URL: https://time.com/5181153/sunlight-flu-prevention-study/
“Does the sun kill the new coronavirus? Expert explains” 2020-01-28 18:20:41 GMT+8 | cnTechPost URL: https://cntechpost.com/2020/01/28/does-the-sun-kill-the-new-coronavirus-expert-explains/
Alternative Sources
“Coronavirus and the Sun: a Lesson from the 1918 Influenza Pandemic” by Richard Hobday, March 10, 2020, Medium (URL: https://medium.com/@ra.hobday/coronavirus-and-the-sun-a-lesson-from-the-1918-influenza-pandemic-509151dc8065)
“Vitamin D, Sunlight, and Pneumonia” Sunlight Institute, (5.11.2011 — could be May 11, 2011 or 4 November 2011 depending on date format), (URL: http://sunlightinstitute.org/vitamin-d-sunlight-and-pneumonia/)
Scholarly and Scientific Articles
“The Open Air Treatment of Pandemic Influenza” by Richard Hobday and John Cason, American Journal of Public Health, July 8, 2008 (URL: https://ajph.aphapublications.org/doi/full/10.2105/AJPH.2008.134627)
“Sunlight and Protection Against Influenza” by David Slusky, Richard J. Zeckhauser NBER Working Paper No. 24340 Issued in February 2018, Revised in January 2019 URL: https://www.nber.org/papers/w24340
Beard, Jeremy A et al. “Vitamin D and the anti-viral state.” Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology vol. 50,3 (2011): 194-200. doi:10.1016/j.jcv.2010.12.006 URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3308600/
Abstract
Vitamin D has long been recognized as essential to the skeletal system. Newer evidence suggests that it also plays a major role regulating the immune system, perhaps including immune responses to viral infection. Interventional and observational epidemiological studies provide evidence that vitamin D deficiency may confer increased risk of influenza and respiratory tract infection. Vitamin D deficiency is also prevalent among patients with HIV infection. Cell culture experiments support the thesis that vitamin D has direct anti-viral effects particularly against enveloped viruses. Though vitamin D’s anti-viral mechanism has not been fully established, it may be linked to vitamin D’s ability to up-regulate the anti-microbial peptides LL-37 and human beta defensin 2. Additional studies are necessary to fully elucidate the efficacy and mechanism of vitamin D as an anti-viral agent.
“Vitamin D and the Immune System” by Cynthia Aranow, MD, Investigator Author information Copyright and License information
Abstract
It is now clear that vitamin D has important roles in addition to its classic effects on calcium and bone homeostasis. As the vitamin D receptor is expressed on immune cells (B cells, T cells and antigen presenting cells) and these immunologic cells are all are capable of synthesizing the active vitamin D metabolite, vitamin D has the capability of acting in an autocrine manner in a local immunologic milieu. Vitamin D can modulate the innate and adaptive immune responses. Deficiency in vitamin D is associated with increased autoimmunity as well as an increased susceptibility to infection. As immune cells in autoimmune diseases are responsive to the ameliorative effects of vitamin D, the beneficial effects of supplementing vitamin D deficient individuals with autoimmune disease may extend beyond the effects on bone and calcium homeostasis.
J Investig Med. Author manuscript; available in PMC 2012 Aug 1.Published in final edited form as:J Investig Med. 2011 Aug; 59(6): 881–886. doi: 10.231/JIM.0b013e31821b8755PMCID: PMC3166406NIHMSID: NIHMS291217PMID: 21527855
DisclaimerThe publisher’s final edited version of this article is available at J Investig MedSee other articles in PMC that cite the published article.Go to:
Curr Allergy Asthma Rep. 2009 Jan;9(1):81-7.
“Vitamin D, respiratory infections, and asthma.” by Ginde AA1, Mansbach JM, Camargo CA Jr.
Abstract
Over the past decade, interest has grown in the role of vitamin D in many nonskeletal medical conditions, including respiratory infection. Emerging evidence indicates that vitamin D-mediated innate immunity, particularly through enhanced expression of the human cathelicidin antimicrobial peptide (hCAP-18), is important in host defenses against respiratory tract pathogens. Observational studies suggest that vitamin D deficiency increases risk of respiratory infections. This increased risk may contribute to incident wheezing illness in children and adults and cause asthma exacerbations. Although unproven, the increased risk of specific respiratory infections in susceptible hosts may contribute to some cases of incident asthma. Vitamin D also modulates regulatory T-cell function and interleukin-10 production, which may increase the therapeutic response to glucocorticoids in steroid-resistant asthma. Future laboratory, epidemiologic, and randomized interventional studies are needed to better understand vitamin D’s effects on respiratory infection and asthma.PMID: 19063829 DOI: 10.1007/s11882-009-0012-7
The scientific and scholarly articles listed above include links to many other scholarly and scientific articles on the role of Vitamin D in respiratory illnesses.
“Official” Resources
“Vitamin D supplementation and respiratory infections in children” World Health Organization (WHO) (URL: https://www.who.int/elena/titles/vitamind_pneumonia_children/en/)
(C) 2020 by John F. McGowan, Ph.D.
About Me
John F. McGowan, Ph.D. solves problems using mathematics and mathematical software, including developing gesture recognition for touch devices, video compression and speech recognition technologies. He has extensive experience developing software in C, C++, MATLAB, Python, Visual Basic and many other programming languages. He has been a Visiting Scholar at HP Labs developing computer vision algorithms and software for mobile devices. He has worked as a contractor at NASA Ames Research Center involved in the research and development of image and video processing algorithms and technology. He has published articles on the origin and evolution of life, the exploration of Mars (anticipating the discovery of methane on Mars), and cheap access to space. He has a Ph.D. in physics from the University of Illinois at Urbana-Champaign and a B.S. in physics from the California Institute of Technology (Caltech).