|1918 Photo of Camp Brooks Open-Air Hospital Boston - Nat'l Archives|
We feel the menance of the Corona Virus (Covid-19) and the imposed social isolation. Although worse than the typical annual flu, the Corona Virus pales to the worldwide pandemic of the Spanish Flu (isolated as the H1N1 virus). What does this have to do with sunlight? I am indebted to Richard Hobday's well researched article:
Here is his paragraph on "Sunlight and Influenza Infection"
"Putting infected patients out in the sun may have helped because it inactivates the influenza virus. It also kills bacteria that cause lung and other infections in hospitals. During the First World War, military surgeons routinely used sunlight to heal infected wounds. They knew it was a disinfectant. What they didn’t know is that one advantage of placing patients outside in the sun is they can synthesise vitamin D in their skin if sunlight is strong enough. This was not discovered until the 1920s. Low vitamin D levels are now linked to respiratory infections and may increase susceptibility to influenza. Also, our body’s biological rhythms appear to influence how we resist infections. New research suggests they can alter our inflammatory response to the flu virus. As with vitamin D, at the time of the 1918 pandemic, the important part played by sunlight in synchronizing these rhythms was not known."