here is the caimbridge link(with abstract included). if you click on the link it takes you directly there. review article [color=#336699]epidemic influenza and vitamin d j. j. cannell a1c1
, r. vieth a2
, j. c. umhau a3
, m. f. holick a4
, w. b. grant a5
, s. madronich a6
, c. f. garland a7 and e. giovannucci a8
a1 atascadero state hospital, 10333 el camino real, atascadero, ca, usa
a2 mount sinai hospital, pathology and laboratory medicine, department of medicine, toronto, ontario, canada
a3 laboratory of clinical and translational studies, national institute on alcohol abuse and alcoholism, national institutes of health, bethesda, md
a4 departments of medicine and physiology, boston university school of medicine, boston, ma, usa
a5 sunarc, san francisco, ca, usa
a6 atmospheric chemistry division, national center for atmospheric research, boulder, co, usa
a7 department of family and preventive medicine, university of california san diego, la jolla, ca, usa
a8 departments of nutrition and epidemiology, harvard school of public health, boston, ma, usa abstract
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’.
(accepted august 5 2006)
(published online september 7 2006)
as for the medscape one you have to login to access the article so here it is - this is the abstract and intro. vitamin d for treatment and prevention of infectious diseases: a systematic review of randomized controlled trials
alexandra v. yamshchikov, md; nirali s. desai, md; henry m. blumberg, md; thomas r. ziegler, md; vin tangpricha, md, phd, face authors and disclosures
published: 08/31/2009 abstract objective:
to review the existing human controlled intervention studies of vitamin d as adjunctive therapy in settings of infection and provide recommendations for design and implementation of future studies in this field on the basis of the evidence reviewed. methods:
we conducted a systematic review of randomized controlled clinical trials that studied vitamin d for treatment or prevention of infectious diseases in humans. studies from 1948 through 2009 were identified through search terms in pubmed and ovid medline. results:
thirteen published controlled trials were identified by our search criteria. ten trials were placebo controlled, and 9 of the 10 were conducted in a rigorous double-blind design. the selected clinical trials demonstrated substantial heterogeneity in baseline patient demographics, sample size, and vitamin d intervention strategies. serious adverse events attributable to vitamin d supplementation were rare across all studies. on the basis of studies reviewed to date, the strongest evidence supports further research into adjunctive vitamin d therapy for tuberculosis, influenza, and viral upper respiratory tract illnesses. in the selected studies, certain aspects of study design are highlighted to help guide future clinical research in the field. conclusion:
more rigorously designed clinical trials are needed for further evaluation of the relationship between vitamin d status and the immune response to infection as well as for delineation of necessary changes in clinical practice and medical care of patients with vitamin d deficiency in infectious disease settings. introduction
the link between vitamin d deficiency and susceptibility to infection has been suggested for longer than a century, with the early observation that children with nutritional rickets were more likely to experience infections of the respiratory system, leading to the coining of the phrase "rachitic lung".
the isolation of vitamin d3 from cod liver oil, which was used to treat tuberculosis (tb) in the 1930s, led to its widespread use in tb treatment and prevention, until the introduction of antiinfective chemotherapy in the 1950s.
more recently, epidemiologic studies have demonstrated strong associations between seasonal variations in vitamin d levels and the incidence of various infectious diseases, including septic shock,
our understanding of vitamin d metabolism and its extraskeletal functions has improved considerably during the past 3 decades. the discovery that vitamin d receptor (vdr) and 1α-hydroxylase, the enzyme necessary for conversion of vitamin d into its active form, are present in cells of the immune system, including circulating mononuclear cells,[6,7]
has revolutionized the field of vitamin d immunology. moreover, the discovery of nonskeletal functions of vitamin d has reinvigorated interest in vitamin d as a potential modulator in a variety of disease states.[8-10]
recent studies have demonstrated that vitamin d regulates the expression of specific endogenous antimicrobial peptides in immune cells
; this action leads to a potential role for vitamin d in modulating the immune response to various infectious diseases.
these findings highlight the need to refine our understanding of the nonskeletal functions of vitamin d through future controlled studies of vitamin d supplementation and clinical outcomes in specific disease states. in this report, we focus on reviewing the existing human controlled intervention studies of vitamin d as adjunctive therapy in settings of infection and provide recommendations for design and implementation of future studies in this field.