Bird ‘flu is on the rounds again. You may remember that last year the wild birds most affected by the fatal disease were Gannets. This year it appears so far to be terns in the Republic of Ireland and Black-headed gulls in Northern Ireland that are worst affected.
Bird ‘flu has been around for decades. It flares up now and again usually in autumn time. It is caused by a virus. When the virus breeds, mistakes, called mutations, sometimes happen when DNA replicates itself. Most mutations are harmful or damaging and consequently die out.
However, now and again a mutation occurs that is beneficial to the virus in that it has survival value. The present result of a beneficial mutation is a strain of the virus code-named H5N1. It was first identified in China in 1996 and since then it has spread around the world. The benefit to the virus is that the mutation is highly pathogenic making it easy for the disease to spread and for the virus to thrive.
The virus passes from bird to bird very easily. It is more difficult for the virus to pass to other animals and to humans. However, hundreds of people have picked up bird ‘flu and, tragically, many have died from its impact. Consequently, people are advised not to touch the carcasses of dead birds.