how long does upper respiratory infection last
Furthermore, different organisms require varying time of onset from when they enter the body to when symptoms occur (incubation time). Some of the common pathogens for upper respiratory infection and their respective incubation times are the following: 1  Thinoviruses, 1-5 days; 2  Group A streptococci, 1-5 days; 3  Influenza and parainfluenza viruses, 1-4 days; 4  Respiratory syncytial virus (RSV), 7 days; 5  Whooping cough (pertussis), 7-21 days;