hi jno
yes in both cases - it might be Dubrovnick
no Caffa
that the Mongol army hurled plague-infected cadavers into the besieged Crimean city of Caffa, thereby transmitting the disease to the inhabitants; and that fleeing survivors of the siege spread plague from Caffa to the Mediterranean Basin. 1346
now it is poss - the fleas er flee from a cooling corpse and seek warmer climes...
and in an early Ducky-man from uncle part - David McCallum plays an English Officer in The Indian War - who has just done that. Films may not be true
and it is here
https://www.history.com/news/colonists-native-americans-smallpox-blankets#:~:text=North%20American%20colonists'%20warfare%20against,and%20linens%20contaminated%20with%20smallpox.
but may not be true - smallpox is spread by fomites ( er linen and blankets)
Siege of Athens 300BC - Spartans led everyone go INTO the city, knowing the overcrowding would promote disease - which it did
Purpura - so badly described ( went purple and popped) that we cant make out what it was.