Bird flu outbreak confirmed on duck breeding farm in Yorkshire The Department for Environment, Food & Rural Affairs (Defra) said it has confirmed at least one case of the virus at the farm. But they insisted the risk to public health is "very low," and said they are embarking on a cull of all poultry at the stricken farm. A Defra spokeswoman said: "We have confirmed a case of avian flu on a duck breeding farm in Yorkshire - the public health risk is very low and there is no risk to the food chain. We are taking immediate and robust action which includes introducing a 10km restriction zone and culling all poultry on the farm to prevent any potential spread of infection. A detailed investigation is ongoing. We have a strong track record of controlling and eliminating previous outbreaks of avian flu in the UK. Bird flu, or avian flu, is an infectious viral illness that spreads among birds. In rare cases it can affect humans. The NHS website states: "There are many types of bird flu, most of which are harmless to humans. However, two types have caused serious concern in recent years. These are the H5N1 and H7N9 viruses. Although these viruses don't infect people easily and are usually not transmitted from human to human, several people have been infected around the world, leading to a number of deaths. Other bird flu viruses (particularly H7N7 and H9N2) have also infected people, but these have rarely caused severe illness.