It’s a word for the return of the creeping crud—the Wuhan flu kind of crud in this case—and I’ve got it bad this time. Caught it in the hospital both times. Starting to believe the hospital is not a safe place to be.
“Crud” is used more for the dried-up remnant of something disgusting or repugnant or “raw,” as with a deposit of filth or from a weeping sore from a disease, or excrement, or “issue” (blood, pus, ejaculate), or for someone or something that embodies those. “Curd” is likely a regional dialect variant (middle English). So they’re all related words (cruel, crude, crud, curd).
But I have a very hard time reading or using recrudescence simply to imply the return or repeat of something, because it really means the repeat process of becoming/depositing/exposing something FILTHY or disgusting to the average person, such as dried feces/pus/ejaculate.
(Of course, one’s own poo doesn’t stink, etc.).