> is because the cold evolves The coronaviruses that cause colds (such as CoV-OC43) don't mutate much. Immunity to them doesn't last long for reasons that ar

> is because the cold evolves The coronaviruses that cause colds (such as CoV-OC43) don't mutate much. Immunity to them doesn't last long for reasons that aren't well understood. Some other viruses that cause colds escape immunity through mutation, other non-CoV cold causing viruses escape are like CoV and also just have short immunity periods without mutation.