Due to bird flu, everyone who has outdoor birds e.g. hens, ducks and geese need to keep them in or put them in their run as long as it has a cover for a month/21 days, but to make sure I would keep them in for 28 days. The main way they could get the flue is by poo/faeces but there are other ways as well.
Hopefully if you have any birds they are going to be ok (they should ok be if you follow the instructions but if they do I hope they get better)
More information from the Government is on their website.