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.
In the center of the Triangle is time. Most infectious diseases have an incubation. periodâthe time between when the host is infected and when disease symptoms. occur. Or, time may describe the duration of the illness or the amount of time a. person can be sick before death or recovery occurs.