In Spores, filmed in 2004, Lionel, a very depressed man, says [I'm paraphrasing] Spores!! They're all over!! They'll get into your lungs! And this is one of the episodes where reality comes crashing into a gentle comedy.
I thought the same last summer when I watched that episode Adanor. It is as though Roy Clarke could see into the future when he wrote that episode. Roy Hudd verbally painted a good picture about the invasion of the invisible. I do hope that we will soon see victory in this World Wide battle.