Sam, I hope the best for your friends. This may sound stupid and obvious but it is the only advice I have on this. Have them take vitamin C in any way they can. It is what I use at home. It is not a cure, but I'm convinced it helps me.
Thanks Archimid,
Depending on the form and source, it might. Quercitin is a part of the vitamin C complex in rose hips and others. Quercitin is known to have helped patients with SARS1. And the supercomputer modeling done by the US Department of Energy identified Quercitin, Luteolin and Yerba Santa as three things that had some of the highest affinities for the ACE2 receptor.
Yerba Santa helps me with lung stuff a lot. Most over the counter or even prescription things do not. I lack a series of critical CYP450 enzymes to convert those to their active forms.
As a result I have had to find pharmacognicolgic solutions (plant source rather than pharmaceuticals). For me in general for lung stuff, Quercitin helps. Yerba Santa helps more. Yerba Mansa too. Sage is somewhat helpful. And oregano seems to be very helpful. But that might just be my love of fish tacos with cabbage and lots of green tomatillo salsa that is about half oregano and cilantro. Then too it might be the cilantro. Cilantro and flat leaf parsley have wonderful medicinal properties.
For pain Corydalis Ambigua (Yanhusuo) is great. So are California Poppy, Tree Peony Root, and magnesium as taurate or glycinate, or skin applied magnesium oil (magnesium chloride hexahydrate). These are all hugely helpful for me. Be careful of taurate with kidney issues. That is not an issue for me. Wild Lettuce should be very useful too, though I haven't tried that. Ditto for myrrh and frankincense.
For vitamin C, sodium ascorbate is better for me than vitamin C proper. It's much easier to tolerate. And an extremely high dose blast of that plus natural vitamin A and D stops coughing. Careful with that though, you can hurt yourself if you don't know what you are doing.
I did recommend Quercitin to them. It is widely and easily available, and well tolerated. It has a very short biological half life. I have yet to find literature or reports, anecdotal or studies detailing success or failure of that, and if successful, at what sort of dosages and when those were helpful.
I am not a doctor, and these are not recommendations for anyone but me.
Addenda: Something I have not seen any data on yet is the differences in CYP and related enzymes, and other genetic differences in the people who have survived versus those who died, or in the various treatments. This is a relatively new but hugely important area. The CYP450 enzymes (and others) are hugely important in affecting the metabolism of drugs in the body. This can and does have dramatic impacts on choices of medications. Yet the vast majority of people have not been tested for their enzyme statuses, and the physicians have not generally been trained in this yet. There are specific exceptions to that.
Likewise, natural variations in immune function can have huge importance, as can the HLA and HNA typing. I have seen no data on that either. One example here is that certain genetic variations allowed some Europeans to survive the Black Death. Their genetic descendants have often inherited that same native resistance. And that also provides huge resistance to HIV.
This is a double edged sword though. Bacteria and Virii adapt as well. Many important autoimmune diseases have as their origin the HLA genetics and this ancient and on going war.
We do know from studies on this outbreak that people with blood type O are considerably less at risk than types A, B or AB. There have been hints about rhesus blood types too, though I haven't seen that confirmed. I have heard nothing at all about the many other blood group families (e.g. Colton, Kell, Kidd, Lutheran, ...) and whether these cause any differences in susceptibility or disease progression.
There was suggestion early on of a dozen snps associated with the ACE2 receptor that might give indications of differences in susceptibility or disease severity. I have not seen any follow ups on that.
Sam