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.
Contagious Period. An adult infected with influenza may be contagious from one day before symptoms start to 5 to 7 days after becoming sick. Children may continue to be contagious for longer than 7 days. Staying home until your contagious period has likely passed will help you avoid passing the flu on to other people.