Covid was always known to be a far more than respiratory illness. I think the list of announced symptoms is now far too short (dumbed down). Viral illnesses have always been well known to produce greatly varied presentations from patient to patient.
I had measles at 2, mumps at 5 and 13, chicken pox at 20 (which comes back as chronic encephalitis and shingles, fortunately slight). I remember having sensitive hearing since young and these pieces of information strengthen my belief the rest of those earlier bouts pulled me down more (than was said at the time) too.
Items on viruses in "wikipedia" relate that viruses of different classes have long been known to potentise each other, not least the herpes type and the corona type. Hence when "viruses" are going around your "whatever" -itis plays up yet again. None of this is new.
A doctor observed many years ago that a heavy cold was making me encephalitic. If I got a heavy upper respiratory infection in recent years (mercifully not often) I would find the shingles flared up worse then. Itchy elbows are the sign for me to slow down, which fortunately my schedule allows.
Antiviral drugs are well established too. One of the many things I don't understand is why they have always been rationed as they are so helpful at both acute and chronic stages, in reducing damage. They only get given if a person was unconscious and happens to go through certain loops at hospital e.g puncture.
What with the authorities' abysmal lateness in reacting and then rubbishing most people's safe plans for earlier reopening, then telling everybody to stop observing the 6 ft rule (though I insist on doing so), the disorganisation now is utterly appalling.