Bird flu

What is bird flu?

Bird flu is a form of influenza which infects - wait for it – birds.
Influenza is a highly infectious disease caused by a group of viruses called Orthomyxoviruses by scientists, or more often called influenza viruses.

Influenza viruses are small.Very small.It would take a billion of them to cover the head of a pin. They’re so small, you can't see them using an ordinary microscope.

All those bits on the surface of the virus particles are proteins. There are two kinds ofprotein on this virus. They're called haemagglutinin and neuraminidase. To make it easier to remember, I'll call them the H and N proteins.

Those two proteins are important.

The H protein lets the virus grab hold of cells and infect them.
The N protein lets the virus get out of the cells it has infected.

The virus needs those proteins. Without them, it can't reproduce. But those two proteins are also the virus' weak point and the way we can attack it.

How do you get the flu?

You catch the flu from respiratory secretions of another infected person. Yes, that's right folks, we're talking snot here! If someone coughs or sneezes near you, you may breathe in some of those secretions containing flu virus particles. More often however, you pick up the virus from an infected object that the other person has touched, then infect yourself by putting your fingers in your mouth or up your nose (yes you do, I've seen you).

The flu virus infects the cells which line your airways. Normally, these are happy little cells working day and night like the ones in this video to clear out all the dirt you breathe in.

But when they get infect with flu virus, they die.

And that's bad news, because you need those cells. As well as dirt, they clean out bacteria that you breathe in. And if they aren't there to do that, you're in trouble. Not many people die from flu virus directly. Most people who die of flu do so from pneumonia - their lungs become infected with bacteria.

But this is bird flu:

As well as humans, the really nasty types of influenza, the ones that make us ill, can also infect birds as well as other mammals such as horses, ferrets and pigs. And that's where the trouble starts. Flu virus likes to infect birds, particularly water birds such as ducks, geese and seabirds. And they don't stay in one place. They go on holiday. They may call it migration, but we both know it's just a holiday. And they take their flu viruses with them. And if it can't find a waterbird, the virus will infect a chicken. And humans eat chickens. And pigs.

At the moment, the scariest bird flu that's spreading around the world is called H5N1 (because of the H and N proteins it has). There are lots of other bird flu viruses (avian influenza if you like), but we don't hear much about those. We hear about H5N1. Because it kills people. But not very well yet.

Imagine that the world is gripped in the throes of the lengthy stalemate of a senseless war that has depleted Europe of most of its young men and resources, and those that remain are destitute, dispirited, starving, and suffering from the lost of loved ones. In the midst of this war, a formerly rather innocuous disease suddenly mutates into a new killer strain which infects all corners of the globe, from Alaska to Africa, within a matter of weeks. This new disease is not only remarkably contagious, but it is so lethal and destroys so many lives in such a short time-frame that even the ghastly global war pales in comparison. The scariest aspect of this tale is that it is not fiction.

So what’s the worst that could happen?

w          A pandemic of human-adapted avian influenza.

w          Such a virus could have a mortality rate of 30-40%.

w          Within a few months 10-25% of the world's population could be infected.

w          6.3 billion * 0.4 * 0.25 = over half a billion deaths.

w          Or worse…

By Gulyás Szabolcs