Highly pathogenic avian influenza H5N1 at a premises near Louth, East Lindsey, Lincolnshire.
Definitive requirements are set out in the published declarations for each disease control zone currently in force.

For further information see the ‘Cases and disease control zones’ section on GOV.​UK: https://www.gov.uk/guidance/avian-influenza-bird-flu-cases-and-disease-control-zones-in-england#cases-and-disease-control-zones

You can also check if specific areas are in a zone by using the interactive map available on GOV.​UK: https://defra.maps.arcgis.com/apps/webappviewer/index.html?id=8cb1883eda5547c6b91b5d5e6aeba90d