What retired doctors (and nurses, and engineers, etc) can do during CoVID-19
You asked whether you should volunteer to go back to work, as a front line physician, during the coronavirus/CoVID-19/SARS-CoV-2 crisis/outbreak.
First of all, let me reiterate what someone else pointed out. As we know from emergency management, the first rule is not only "first, do no harm," but, more specifically, "first, do no harm--to yourself." You (and I) are old, Father Martin. Not only are the old particularly susceptible to the virus, but (for reasons not yet either verified or fully understood) front line medical workers also seem to be particularly susceptible. Going back in as a front line worker may not be the best use of your skills and experience. (As I mentioned earlier, doing your bit with providing good public advice and remote suggestions to research will free up the time of the front line people who would otherwise be having to do it. Even doing public media appearances on their behalf might give them some time they can use in other ways. Like just taking a rest.)
Right off the top, I'd suggest that you start to reach out to other retired doctors (and other professionals). I know that lots of them have already volunteered to return to active service. But I suspect that some of them are concerned, as you are, about the dangers (or are under family pressure, like I am), and may be wondering about how best to proceed. You could be the founder of Doctors-(Nurses, Engineers, Etc)-Without-Paycheques, and get a wealth of skill and experience mobilized in some interesting new directions. (I've already tried with my offer/suggestions about remote/virtual events.) Yes, with the hoarding and panic buying going on we are having to spend more time just getting the necessities of life, but we still have some time to contribute. (Maybe we can get a retired psychologist/anthropologist/social engineer to come up with some way to reduce the panic buying ...)
As I mentioned, one of the first things you/they can do is search out and fight mis- and disinformation with facts and analysis. Most people in the world don't have your knowledge of disease, disease vectors, hygiene rules, transmission vectors, the lifetime of an infectious agent outside the body, the difference in effectiveness between soap and hand sanitizer, or even the difference between a bacteria and a virus. Most people are scared because they are relatively ignorant about these things. (They may not be completely ignorant, and may not be ignorant of other things, but they don't know as much as you do about the specifics.) They are bombarded by news stories about people getting sick, and people dying. They are scared (and also don't know as much as we do about risk analysis and calculation). They feel powerless, and "wash your hands" doesn't feel like it should be enough. I saw the same things in the early days of computer virus research. People felt scared and didn't have enough information so they either a) didn't do anything and ignored the whole situation, or b) believed any random myth they heard (like "use Macs" :-) because at least it seemed like they were doing something.
I'd also reach out to students. A lot of them have a lot of time on their hands right now. Even if they aren't fully trained, most of them have a lot more information than the general public, and can help. Students will also greatly benefit from working with you and the rest of us old codgers while we try to help in various ways, and they'll get a lot of valuable practical experience in the things medical (and nursing, and engineering, and computer security) schools don't/can't teach them. They've got more energy than we do. And there are some interesting projects they can help with.
As well as the mis/disinformation, there are other questions to be researched. Not being on the front lines, you/we may not be able to research or answer them directly. But some gaga old physician somewhere may have an insight that might be key. These are questions like: Are/Why are front line medical workers at greater risk of CoVID-19? Is ibuprofen actually a risk? Lots of questions fall into this category.
But, probably more importantly, there are some projects that can be undertaken without direct front line contact or exposure. For example, right now there is great concern over the availability of ventilators. There are multiple projects that are looking into low-cost, easy manufacture, "open source design" ventilators. (I wouldn't be surprised if a lot of these projects are being done by students.) (Including at least one project that is being sued over the design of a 3D printed valve, so you might add Intellectual-Property-Lawyers-Without-Paycheques to your list of retired professionals.) Some hospital in Canada is putting out videos (on YouTube?) showing how, with extra tubing and connectors, you can get one ventilator to support up to three patients. You need to get a retired respirologist to see if it will work and a retired engineer to see if it is feasible for manufacture by anyone with less than an engineering doctorate. Also, you, as a risk manager, need to look at the various designs, noting that, in this case, the best may very well be the enemy of the good, and that something that is only 80% effective but can be built with scuba tanks and a child's toy may well save more lives than something that is ninety-nine and forty-four one hundredths percent effective but requires a piece of The One True Cross to work. (You may need to get retired politicians to get these ideas in front of the authorities or retired businessmen to set up manufacturing.)
Think outside the box. A lot of us started work before there was a box.
Now go wash your hands.
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