On the epidemiology of influenza: reply to Radonovich et al

On the epidemiology of influenza: reply to Radonovich LJ, Martinello RA, Hodgson M, Milton DK, Nardell EA. Influenza and ultraviolet germicidal irradiation. Virol J. 2008, 5:14

On the epidemiology of influenza

The epidemiology of influenza swarms with incongruities, incongruities exhaustively detailed by the late British epidemiologist, Edgar Hope-Simpson. He was the first to propose a parsimonious theory explaining why influenza is, as Gregg said, "seemingly unmindful of traditional infectious disease behavioral patterns." Recent discoveries indicate vitamin D upregulates the endogenous antibiotics of innate immunity and suggest that the incongruities explored by Hope-Simpson may be secondary to the epidemiology of vitamin D deficiency. We identify – and attempt to explain – nine influenza conundrums: (1) Why is influenza both seasonal and ubiquitous and where is the virus between epidemics? (2) Why are the epidemics so explosive? (3) Why do they end so abruptly? (4) What explains the frequent coincidental timing of epidemics in countries of similar latitude? (5) Why is the serial interval obscure? (6) Why is the secondary attack rate so low? (7) Why did epidemics in previous ages spread so rapidly, despite the lack of modern transport? (8) Why does experimental inoculation of seronegative humans fail to cause illness in all the volunteers? (9) Why has influenza mortality of the aged not declined as their vaccination rates increased? We review recent discoveries about vitamin D's effects on innate immunity, human studies attempting sick-to-well transmission, naturalistic reports of human transmission, studies of serial interval, secondary attack rates, and relevant animal studies. We hypothesize that two factors explain the nine conundrums: vitamin D's seasonal and population effects on innate immunity, and the presence of a subpopulation of "good infectors." If true, our revision of Edgar Hope-Simpson's theory has profound implications for the prevention of influenza

On the Epidemiology of Influenza: Reply to Radonovich et al

On the epidemiology of influenza: reply to Radonovich LJ, Martinello RA, Hodgson M, Milton DK, Nardell EA. Influenza and ultraviolet germicidal irradiation. Virol J. 2008, 5:14

Insufficient Sun Exposure Has Become a Real Public Health Problem.

This article aims to alert the medical community and public health authorities to accumulating evidence on health benefits from sun exposure, which suggests that insufficient sun exposure is a significant public health problem. Studies in the past decade indicate that insufficient sun exposure may be responsible for 340,000 deaths in the United States and 480,000 deaths in Europe per year, and an increased incidence of breast cancer, colorectal cancer, hypertension, cardiovascular disease, metabolic syndrome, multiple sclerosis, Alzheimer's disease, autism, asthma, type 1 diabetes and myopia. Vitamin D has long been considered the principal mediator of beneficial effects of sun exposure. However, oral vitamin D supplementation has not been convincingly shown to prevent the above conditions; thus, serum 25(OH)D as an indicator of vitamin D status may be a proxy for and not a mediator of beneficial effects of sun exposure. New candidate mechanisms include the release of nitric oxide from the skin and direct effects of ultraviolet radiation (UVR) on peripheral blood cells. Collectively, this evidence indicates it would be wise for people living outside the tropics to ensure they expose their skin sufficiently to the sun. To minimize the harms of excessive sun exposure, great care must be taken to avoid sunburn, and sun exposure during high ambient UVR seasons should be obtained incrementally at not more than 5-30 min a day (depending on skin type and UV index), in season-appropriate clothing and with eyes closed or protected by sunglasses that filter UVR

Psychiatric diagnoses and punishment for misconduct: the effects of PTSD in combat-deployed Marines

<p>Abstract</p> <p>Background</p> <p>Research on Vietnam veterans suggests an association between psychological problems, including posttraumatic stress disorder (PTSD), and misconduct; however, this has rarely been studied in veterans of Operation Iraqi Freedom or Operation Enduring Freedom. The objective of this study was to investigate whether psychological problems were associated with three types of misconduct outcomes (demotions, drug-related discharges, and punitive discharges.)</p> <p>Methods</p> <p>A population-based study was conducted on all U.S. Marines who entered the military between October 1, 2001, and September 30, 2006, and deployed outside of the United States before the end of the study period, September 30, 2007. Demographic, psychiatric, deployment, and personnel information was collected from military records. Cox proportional hazards regression analysis was conducted to investigate associations between the independent variables and the three types of misconduct in war-deployed (n = 77 998) and non-war-deployed (n = 13 944) Marines.</p> <p>Results</p> <p>Marines in both the war-deployed and non-war-deployed cohorts with a non-PTSD psychiatric diagnosis had an elevated risk for all three misconduct outcomes (hazard ratios ranged from 3.93 to 5.65). PTSD was a significant predictor of drug-related discharges in both the war-deployed and non-war-deployed cohorts. In the war-deployed cohort only, a specific diagnosis of PTSD was associated with an increased risk for both demotions (hazard ratio, 8.60; 95% confidence interval, 6.95 to 10.64) and punitive discharges (HR, 11.06; 95% CI, 8.06 to 15.16).</p> <p>Conclusions</p> <p>These results provide evidence of an association between PTSD and behavior problems in Marines deployed to war. Moreover, because misconduct can lead to disqualification for some Veterans Administration benefits, personnel with the most serious manifestations of PTSD may face additional barriers to care.</p

The Role of Vitamin D in Cancer Prevention

Vitamin D status differs by latitude and race, with residents of the northeastern United States and individuals with more skin pigmentation being at increased risk of deficiency. A PubMed database search yielded 63 observational studies of vitamin D status in relation to cancer risk, including 30 of colon, 13 of breast, 26 of prostate, and 7 of ovarian cancer, and several that assessed the association of vitamin D receptor genotype with cancer risk. The majority of studies found a protective relationship between sufficient vitamin D status and lower risk of cancer. The evidence suggests that efforts to improve vitamin D status, for example by vitamin D supplementation, could reduce cancer incidence and mortality at low cost, with few or no adverse effects