My flock got infectious bronchitis and they acted normally with only frequent sneezing that lasted almost a month. I separated the ones who sneezed. They got better, and another group started sneezing. They all went about their normal routine, eating and drinking. I noticed a couple of wrinkled egg shells which can be another symptom. Eventually all chickens got it and recovered over weeks. Since they were carriers for 5 months or more, the new birds I added or hatched got it later. I stopped adding birds for over a year, and no one else got it. The problem with infectious bronchitis virus, is that it can affect egg laying and cause various egg shell problems and oviduct issues. Many of my hens later suffered those reproductive disorders and did not live past 3-4 years. Others lived as long as 10 or 11. IB virus affects young birds more than adult birds.