How does pontiac fever differ from legionnaires' disease?

Quicker. Milder. Both are caused by the legionella germ. Pontiac favor happens quicker. It's milder and doesn't have breathing problems like cough chest pain, pneumonia. Good question!
It is a milder form. Pontiac fever is a milder form of legionnaires' diease, both illnesses caused by the bacterium legionella pneumophila the incubation period is short, from a few hours to 2 days, before the onset of fever and muscle aches. Persons with pontiac fever do not have pneumonia. They generally recover in 2 to 5 days without treatment.