Avian influenza is a cyclical problem, and right now we seem to be at a high point with infections. If your birds become sick with bird flu and end up being culled, you will not be able to restock within a year. We can all take measures to improve our biosecurity.
This advice comes from the British Free Range Egg Producers Association:
We cannot stress enough in this rampant AI outbreak how important it is for everyone to ramp up biosecurity. In addition to the biosecurity messages already made in previous newsletters, it is now clear that the current H5N1 virus is so virulent that boot dipping is not sufficient to kill the virus. Boots must be changed between sheds.
It has also become clear that the virus could be spread on hands. If you handle an (infected) hen in a shed, and change boots and overalls, you could still spread the virus to another shed on your hands. Wash hands thoroughly between shed visits.