Question: what is the incubation period for upper respiratory infection?
Answer: Rhinoviruses and group A streptococci may incubate for 1-5 days, influenza and parainfluenza may incubate for 1-4 days, and respiratory syncytial virus (RSV) may incubate for a week. Pertussis typically incubates for 7-10 days, or even as long as 21 days, before causing symptoms. Diphtheria incubates for 1-10 days.