Picture from Wikipedia: Sponges
Antiviral drugs are a hot topic.
I remember, growing up, there were no such things, just antibiotics, which are effective only against bacterial infections. But about four years ago I had (not contacted) shingles. I'd had it for half a century plus, only it was Chicken Pox (called variola) when I caught it originally; shingles when it flared up again in a different form (called herpes zoster, same virus).
The virus had been dormant in my spinal chord for half a century, but old age or stress or something else brought the monster to life once more. After about a day of wondering why my back hurt somewhat, I suddenly realised what it must be and trotted
off to my excellent doc. Self diagnosis confirmed and doc prescribed acylovir. This had been around from 1980, but I didn't realise. It's on the WHO list of essential drugs which (my words) address a widespread and significant health concen; and are
effective, safe and affordable.
An amazing drug. Main use against herpes viruses, read more here. But the surprising thing is that it was developed from a Carribean sea sponge.
It turns out that sea sponges, from their way of living, have evolved a huge range of chemical biodefence against bacteria, viruses, fungi, protozoa and so on. By exploring these agents some useful drugs have been found. Read more here.