Well, and contrary to the common perception that requires washing chicken before cooking it, a thing that is often transmitted to us by our mother or mother-in-law, or which simply arises from our logic and good culinary sense, yes, it is true, we should not wash chicken pieces under running water before cooking them.
Such a habit which we believe is mandatory from the hygienic point of view can easily, by way of spraying water, cause the spread of germs, essentially the campylobacter bacteria that is found almost systematically in chicken skin during the slaughtering phase. Hence, washing chicken with water causes the dispersion of germs onto our hands and clothes, on the kitchen countertop, on culinary utensils, on nearby raw vegetables, etc. Such a fact would cause intestinal infections that can sometimes be severe especially in young children, pregnant women, elderly people and those suffering from a frail immune system.
Finally, we should remember that these germs, including the campylobacter bacteria, are never destroyed during water-washing. In fact, the only way to completely destroy them is by cooking chicken at a temperature greater than 75 degrees in the deepest parts of such food.