Vitamin D and Influenza --> Re: Mexico swine flu deaths spur global epidemic fears

[Guest guest]

Since there are many Vitamin D advocates on the list this dovetailes into a posting from last year, thought I'd post this new tidbit on flu and Vit D.

 

Kind of interesting that low levels of sunshine/vitamin D (eg winter) and seasonal flu seem to conincide.

 

Wonder what the mechanism for less asthma attacks is?Could just be that kids with less viral infections get less asthma flares, I suppose.

http://news.yahoo.com/s/nm/20100319/hl_nm/us_vitamind_study

 

Vitamin D helps fend off flu, asthma attacks: study

 

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http://www.ajcn.org/cgi/content/abstract/ajcn.2009.29094v1?maxtoshow= & hits=10 & RESULTFORMAT= & fulltext=influenza & andorexactfulltext=and & searchid=1 & FIRSTINDEX=0 & sortspec=relevance & resourcetype=HWCIT

 

Am J Clin Nutr (March 10, 2010). doi:10.3945/ajcn.2009.29094

Randomized trial of vitamin D supplementation to prevent seasonal influenza A in schoolchildren1,2,3

Mitsuyoshi Urashima, Takaaki Segawa, Minoru Okazaki, Mana Kurihara, Yasuyuki Wada and Hiroyuki Ida

1 From the Division of Molecular Epidemiology (MU)the Department of Pediatrics (MU YWHI) Jikei University School of Medicine Minato-ku Tokyo Japan; the Department of Pediatrics Fuji City General Hospital Shizuoka Japan (TS); the Department of Pediatrics Sado General Hospital Sado City Niigata Japan (MO);the Department of Pediatrics Kanagawa Rehabilitation Center Kanagawa Japan (MK).

2 Supported by the Jikei University School of Medicine.

3 Address correspondence to M Urashima, Division of Molecular Epidemiology, Jikei University School of Medicine, Nishi-shimbashi 3-25-8, Minato-ku, Tokyo 105-8461, Japan. E-mail: urashima@...

..

ABSTRACT Background: To our knowledge, no rigorously designed clinical trials have evaluated the relation between vitamin D and physician-diagnosed seasonal influenza.

Objective: We investigated the effect of vitamin D supplements on the incidence of seasonal influenza A in schoolchildren.

Design: From December 2008 through March 2009, we conducted a randomized, double-blind, placebo-controlled trial comparing vitamin D3 supplements (1200 IU/d) with placebo in schoolchildren. The primary outcome was the incidence of influenza A, diagnosed with influenza antigen testing with a nasopharyngeal swab specimen.

Results: Influenza A occurred in 18 of 167 (10.8%) children in the vitamin D3 group compared with 31 of 167 (18.6%) children in the placebo group [relative risk (RR), 0.58; 95% CI: 0.34, 0.99; P = 0.04].

The reduction in influenza A was more prominent in children who had not been taking other vitamin D supplements (RR: 0.36; 95% CI: 0.17, 0.79; P = 0.006) and who started nursery school after age 3 y (RR: 0.36; 95% CI: 0.17, 0.78; P = 0.005).

In children with a previous diagnosis of asthma, asthma attacks as a secondary outcome occurred in 2 children receiving vitamin D3 compared with 12 children receiving placebo (RR: 0.17; 95% CI: 0.04, 0.73; P = 0.006).

Conclusion: This study suggests that vitamin D3 supplementation during the winter may reduce the incidence of influenza A, especially in specific subgroups of schoolchildren. This trial was registered at https://center.umin.ac.jp as UMIN000001373.

Received for publication December 17, 2009. Accepted for publication February 11, 2010.

Don't know if all these are valid, but here is a list of articles from one Vitamin D advocate.

 

http://www.vitamindcouncil.org/science/research/vitamin-d-and-influenza.shtml

 

Featured Studies: Influenza and Vitamin D

Epidemic influenza and vitamin D. — Abstract Epidemiol Infect. 2006 Dec;134(6):1129–40. Review. Epidemic Influenza and Vitamin D. — Full Text (PDF download) Epidemiol Infect. 2006 Dec;134(6):1129–40. Review. On the epidemiology of influenza. — Abstract Virol J. 2008 Feb 25;5:29. Review. On the Epidemiology of Influenza. — Full Text Virol J. 2008 Feb 25;5:29. Review. Commentary. On the epidemiology of influenza: reply to Radonovich et al. Virol J. 2009 Aug 11;6:121. Re: epidemic influenza and vitamin D. — Abstract Epidemiol Infect. 2007 Oct;135(7):1095–6; author reply 1097–8. Re: Epidemic Influenza and Vitamin D. — Full Text (PDF download) Epidemiol Infect. 2007 Oct;135(7):1095–6; author reply 1097–8. Epidemic influenza and vitamin D. — Abstract Epidemiol Infect. 2007 Oct;135(7):1091–2; author reply 1092–5. Epidemic Influenza and Vitamin D. — Full Text (PDF download) Epidemiol Infect. 2007 Oct;135(7):1091–2; author reply 1092–5

snip/snip -- and many more at the link.

 

Locke, MD

Wonder if this works for swine flu?Interesting.http://www.vitamindcouncil.org/newsletter/2006-oct.shtml

Epidemic Influenza and Vitamin Dhttp://www.ncbi.nlm.nih.gov/pubmed/16959053http://journals.cambridge.org/action/displayAbstract?fromPage=online & aid=469543

Epidemiol Infect. 2006 Dec;134(6):1129-40. Epub 2006 Sep 7. Links

Comment in:

Epidemiol Infect. 2007 Oct;135(7):1091-2; author reply 1092-5.

Epidemiol Infect. 2007 Oct;135(7):1095-6; author reply 1097-8.

Epidemic influenza and vitamin D.

Cannell JJ, Vieth R, Umhau JC, Holick MF, Grant WB, Madronich S, Garland CF, Giovannucci E.

Atascadero State Hospital, 10333 El Camino Real, Atascadero, CA 93422, USA. jcannell@...

In 1981, R. Edgar Hope-Simpson proposed that a 'seasonal stimulus' intimately associated with solar radiation explained the remarkable seasonality of epidemic influenza. Solar radiation triggers robust seasonal vitamin D production in the skin; vitamin D deficiency is common in the winter, and activated vitamin D, 1,25(OH)2D, a steroid hormone, has profound effects on human immunity.

1,25(OH)2D acts as an immune system modulator, preventing excessive expression of inflammatory cytokines and increasing the 'oxidative burst' potential of macrophages. Perhaps most importantly, it dramatically stimulates the expression of potent anti-microbial peptides, which exist in neutrophils, monocytes, natural killer cells, and in epithelial cells lining the respiratory tract where they play a major role in protecting the lung from infection.

Volunteers inoculated with live attenuated influenza virus are more likely to develop fever and serological evidence of an immune response in the winter. Vitamin D deficiency predisposes children to respiratory infections.

Ultraviolet radiation (either from artificial sources or from sunlight) reduces the incidence of viral respiratory infections, as does cod liver oil (which contains vitamin D). An interventional study showed that vitamin D reduces the incidence of respiratory infections in children.

We conclude that vitamin D, or lack of it, may be Hope-Simpson's 'seasonal stimulus'. Locke, MD