Just as the news headlines about Ebola have dampened down from boiling to a quiet simmer, Avian Flu has leapt back into the news. The Telegraph headline today sums up the media reporting: "Bird flu strain which can be passed to humans detected in Holland". Meanwhile, even closer to home, the BBC reports that a case of bird flu has been confirmed at a duck breeding farm in East Yorkshire. The ducks are being slaughtered and a 10km (6 mile) exclusion zone is in place. It all sounds as if an apocalypse along the lines of the "Contagious" movie has landed in Europe, but the truth is far less exciting. Avian Flu is a viral disease that is highly infectious between birds. This is the single fact that needs to be stressed more than anything else. It is a bird disease, and the risk to humans is minimal. The strain of avian flu that is in the news is similar as the one which was first seen in Hong Kong in 1997, and has been appearing spasmodically ever since. That one was known as H5N1(H-five-N-one), a name that describes the type of proteins on the virus particles. The Netherlands strain is the H5N8. The strain in Yorkshire has been identified as an H5 strain but further details are not yet available. It is true that humans can be infected by such strains of the virus, but the risk of this is so small as to be almost negligible. Hundreds of millions of birds have died because the disease spreads rapidly from bird to bird, and because authorities react to viral outbreaks by carrying out mass slaughtering of poultry flocks in an attempt to eliminate the virus. When humans have been infected, the virus has not spread from person to person. It has remained as a bird virus only, with humans only occasionally getting in the way, usually when they are working in close proximity to infected birds when they inhale viral particles. If Avian Flu reached the UK, everyone working with poultry would know to be ultra-careful about hygiene, so the risk of humans dying of bird flu would be minimal. There is no such thing as a human pandemic of bird flu. Readers may then wonder why there seems to be a type of hysteria around Avian Flu. The reason for this is the potential for a change in the virus which could indeed lead to a human pandemic. The avian virus could mutate into a new strain of virus that is highly infectious to humans. If this happened, the new Human Flu virus would spread across the world rapidly. This is what happened in 1918, when 50 million people worldwide died in a flu pandemic and the authorities are justifiably concerned about the risk of a repeat of this. Mutation of the virus is only likely to happen if a human who is already suffering from a normal, harmless human flu virus infection picked up an Avian Flu virus at the same time. If the two viruses were active in the same human body at the same time, they may exchange genetic material. The result could be a new mutated virus that was a combination of the harmless human flu and the dangerous bird flu. If this new virus spread from the first victim to other people, it could signal the start of a new global human pandemic similar to 1918. Modern high volume, low-cost international travel would mean that the new virus could spread very rapidly indeed. This is why the authorities take outbreaks of Avian Flu so seriously. In Hong Kong originally in 1997, 1.5 million birds were slaughtered. The pattern has been repeated elsewhere – whenever the virus, or similar ones, are discovered, the poultry population is slaughtered. These strict control measures are very effective in stopping the spread of the disease amongst birds. Despite such radical efforts to control the virus, it does continue to spread. Migrating wild birds – waterfowl such as ducks, geese and swans - are partly to blame, but infected poultry products – such as untreated manure - may also contribute when they are moved out of infected areas. International trade in poultry can also be significant, and the mass intensification of poultry meat production means that when outbreaks occur, hundreds of thousands of birds can rapidly be affected. The public in the UK do not need to worry too much about these latest outbreaks in the Netherlands, but people should be aware that if they do come across sick or dead wild waterfowl (such as swans), they should let the authorities know at once. To find out more about the UK government's response to the bird flu vet, see this link. It's a helpful government website: no frightening headlines, no nonsense: just the simple facts.