Chicks lack immunity to a wide array of viral, bacterial, fungal and protozoal diseases that may be found around the world and at all times. Strong biosecurity measures are particularly important when caring for newly hatched chicks.

Fowlpox is an old viral poultry disease that frequently affects backyard flocks. It is found worldwide and was first described as early as the 17th century. It is most commonly seen in chickens and turkeys, but almost every bird species can become infected including wild birds and indoor birds like canaries.