It doesn't get a lot of attention ... but any major viral infection can and do cause long-hauler symptoms, I'm not even sure long COVID is more common than "long influenza", "long meningitis", etc.
When my son was an infant, he contracted RSV like most babies do. Instead of just snapping right back after getting over the infection, however ... he required home-administered albuterol treatments for about another year-and-a-half.
https://www.medicalnewstoday.com/articles/326619#what-is-it
https://pubmed.ncbi.nlm.nih.gov/26475444/
https://www.vox.com/22298751/long-term-side-effects-covid-19-hauler-symptoms