Seeing the word "diphtheria" brings home to me how many illnesses that used to be very common are now rarely heard about.
I was born in 1949 and it was common when I was growing up to hear of illnesses like diphtheria, polio, or tuberculosis as well as illnesses that went round schools regularly like measles, mumps, chickenpox or rubella (German measles).
Luckily we began to get treatment for all these illnesses and now (as far as I know) they are very rare (though with many young parents now NOT getting their children inoculated the numbers are rising for some of them).
When I was young I had no idea how serious some of these illnesses were, or how long they took to treat.
I was amazed when I found out some people with tuberculosis could be in hospital a year or more.
The comedy writing duo Galton and Simpson (Hancock Half Hour, Steptoe and Son etc) met while they were both in hospital suffering from tuberculosis.
Saw a drama / comedy film the other day called "Twice round the Daffodils" about a group of men spending a year in hospital with tuberculosis. More here:
en.wikipedia.org
I know we have coronavirus at the moment, but we are so lucky that many of these illnesses that were common only 40 or 50 years ago are now fairly rare.