Besides being direct carriers of disease, nuisance birds are frequently associated with over 50 kinds of ectoparasites, which can work their way throughout structures to infest and bite humans. About two-thirds of these pests may be detrimental to the general health and well-being of humans and domestic animals. The rest are considered nuisance or incidental pests.
A few examples of ectoparasites include:
- Bed bugs (Cimex lectularius) may consume up to five times their own weight in blood drawn from hosts which include humans and some domestic animals. In any extreme condition, victims may become weak and anemic. Pigeons, starlings and house sparrows are known to carry bed bugs.
- Chicken mites (Dermanyssus gallinae) are known carriers of encephalitis and may also cause fowl mite dermatitis and acariasis. While they subsist on blood drawn from a variety of birds, they may also attack humans. They have been found on pigeons, starlings and house sparrows.
- Yellow mealworms (Tenebrio molitor), perhaps the most common beetle parasites of people in the United States, live in pigeon nests. It is found in grain or grain products, often winding up in breakfast cereals, and may cause intestinal canthariasis and hymenolespiasis.
- West Nile Virus while West Nile is technically not transmitted to humans from birds, humans can get infected by the bite of a mosquito who has bitten an infected bird. The obvious lesson is that the fewer birds there are in any given area, the better. This translates into a smaller chance of an infected bird in that area, a smaller chance of a mosquito biting an infected bird and then biting a human.