There are four main types of air pollution sources: mobile sources â such as cars, buses, planes, trucks, and trains stationary sources â such as power plants, oil refineries, industrial facilities, and factories
Incubation Period: Average 9-10 days. Period of Communicability: Highly communicable in the early phase and at the beginning of the paroxysmal cough stage (first 2 weeks). The child is no longer contagious after 5 days of treatment.
To a lesser degree, discharge from skin lesions (the scabs are not infectious). Incubation: The incubation period is 14 to 21 days. Contagious Period: The period of communicability is from 1 day prior to the rash to 5 or 6 days after the onset of the rash.