That - unreviewed - article by a center focused on alternative medicine (i. e. likely bullshit) talks about how phototherapy is an unproven and near-forgotten method (elsewhere you'll read that it is alternative medicine and little better than homoeopathy or howling at the moon) and recommend looking into a possible use in otherwise hopeless cases (i. e. nothing to lose) of multi-drugresistant BACTERIAL infection and life-threatening sepsis.
SARS-COV-2 is a virus.
This is rather a side tangent but there are actually some fairly exciting developments in medicine taking advantage of light, though they have nothing to do that stuff. Some of the most interesting are more for diagnostic purposes in medical imaging. These compounds, known as
near-infrared dyes, allow for extremely find levels of detail in tissues that couldn't normally be imaged. Essentially, organic chemists are working on developing new classes of materials that dissolve in aqueous media (or are compatible in aqueous media via some added linker), have a good quantum yield (roughly the percentage of light absorb/emission in its known absorbance/emitted range), and primarily absorb light in the near-infrared range. The reason near-infrared light is chosen is our tissues are actually rather transparent to it allowing light to pass through our body with minimal scattering or absorbance. It's a somewhat narrow window though because water has a lot of absorbance modes in the infrared range. Overall there are a lot of challenges with this.
There are a lot of exciting developments, and some working prototypes. What these will be most useful for is tumor imaging. You can visualize small cappaliry veins at a resolution you haven't been able to achieve. Once the dyes have been made you conjugate them with an antibody or some biological ligand moiety that will bind to the tissues of interest.
I mean, check out this image. This is of a mouse head, the middle image is with shorter waved infrared which tissues too broadly scatter, so you don't get many details even with a good dye. The right image is at a much longer infrared dye (in the "shortwave" range; yeah the name is kinda confusing). MUCH less scattering, and with a good dye you get SO much detail! This has the potential to completely revolutionize medical imaging.
It really shows you how much detail is enabled by these.
Ellen Sletten is whom I consider to be the biggest innovator with this right now as she is pushing for shortwave infrared dyes in the 1300nm range (most dyes are less than 1000nm where scattering is a lot higher). The shortwave goal is much more challenging, but with much higher potential. One of the primary issues right now is with solubility. You have to make some pretty big
chromophores to lower the absorbance frequency as low as it is. Typically, the lower you make the absorbance frequency the more unstable the molecule is and/or it becomes more reactive or toxic (sometimes significantly so). You can somewhat get around this by repeating chromophore patterns, but they are almost always aromatic rings which render the molecule insoluable in aqueous AND organic media. Finding that sweet spot is like asking little old lady with coke glasses to thread a needle. It is doable though, and people are figuring it out.
Why am I bringing this up? Well, it's just flat out interesting, but also to point out that in order to take advantage of light therapy of any kind... it gets pretty complicated. Biology is complex as fuck. Explaining my example hear illustrates an example of what REAL innovation is. There are SO many little details you need to account for. There are no quick fixes or easy solutions. Also note the example here uses infrared light; it's quite harmless to the body. Ultraviolet? Not so much. That's just, pretty much universally bad for the body, much more so to expose it to internal parts that haven't evolved to tolerate UV exposure like our outer parts are. There are bound to be a ton of unforseen consequences even if it were to kinda sorta almost work.
Like any "treatment" this administration pushes out, it's a complete non-starter on the surface from a scientific angle. So much so that even a lay person can tell it's bullshit.