No person shall create, allow, or maintain a fly nuisance; nor knowingly allow waste to become a harborage, attractant or food source for rodents, or result in unreasonable production of odors resulting in the depreciation of adjacent property or comfortable enjoyment of life thereon. Upon knowledge of such fly nuisance, rodent infestation or unreasonable odor production, or after having received a written abatement order from the county health officer, said person shall at once proceed and continue in good faith with the abatement of such fly nuisance or control and elimination of rodents or source of unreasonable odor. (Prior gen. code § 3-97.2)