The bacterium Bordetella pertussis is the primary whooping cough cause. There are no other causes, and the infection follows no distinct seasonal pattern. People may become infected with the bacteria by breathing in tiny droplets released into the air by an infected person's cough or sneeze.
There are approximately 1,892.7 milliliters in 1 half-gallon of volume. That works out to 3,785.4 milliliters per gallon, 1.892 liters per half-gallon and 3.785 liters per gallon.
Quick Answer. There are five fifths in a gallon, and 2.5 fifths in half a gallon. A fifth is a unit of measurement formerly used in the United States for distilled beverages. Continue Reading.