Avian Flu, How Flu Spreads, Anti-Flu Drugs, and how to avoid Influenza

Anyone who has spent ages rummaging around in their bag for their keys on a dark evening, usually in the rain, will appreciate a new self-illuminating solar-powered handbag designed by Brunel University's Rosanna Kilfedder. Powered by an internal battery, the bag's electroluminescent lining glows whenever the zip is opened, showing you what's inside, and switches off again after 15 seconds to prevent the battery going flat if the bag is left open by accident. On sunny days the external solar panels help to recharge the battery, which can also be used to run a mobile phone, or even a portable music player. Dubbed Sun Trap, the design has won backing from the Brunel Enterprise Centre and, if all goes according to plan, could be helping people locate their keys, lipsticks, and other things lurking in the bottoms of their bags, within a year.

Chris - We've heard a little bit from Paul Digard about how flu is a virus. But could you just crystallise for us, what actually is the flu and where does it come from?

John - Well we can start with what it looks like, which is a football with lots of spikes sticking out around the outside. I like your idea of an escape kit, because the virus does have an escape kit and it needs it too. One of those spikes on the outside of the football is a mushroom shaped thing and that's called a neuraminidase, and that helps the virus chop its way through the layer of snot, as it were, and this is a very very very important layer. In fact, we put a lot of hope in this layer if the virus actually comes on the scene. The new drugs against flu, the ones we will be depending on, they're also targeted against this mushroom as well, so it's a pretty important part of the virus.

Chris - Where did it come from in the first place?

John - We think the virus came from birds and that flu actually is a bird virus. Ten or eleven thousand years ago when Cambridge still had metres of ice on it, there weren't many humans around but there were plenty of birds. A thousand years later, there were maybe 20, 30 or 40 humans here, and then from then on, viruses like influenza which need a person to person transmission, they could spread. It's at that stage that we think the virus did a leap out of birds and into humans. Ever since, the birds such as ducks and geese have been the reservoir and we have also had the virus evolving with us. That's the position we're in at the moment. The question is whether a new virus is going to jump out of the reservoir and catch us all unawares.

Chris - What stops it doing that anyway? Presumably it's because there are now two types of virus: bird types and human types that it doesn't just chop and change all the time. Why should it have a barrier?

John - Well when were you last in contact with a migrating goose or a swan?

Chris - Well I saw some fly over my house the other day.

John - Yes but did you go up and rub your nose into its beak? Probably not.

Chris - Actually no. I have to admit that I didn't.

John - Well that underlies the main problem. How does it get from one to the other? What we think happens is that the ten of thousands of geese that are currently moving around Europe get tired, they fly down onto a lake, pond or canal and they excrete virus. They are silent carriers. They don't know they're infected and they don't feel unwell. They let their waste out into the lake. Then along comes a domesticated goose or duck, it picks up the virus, doesn't get any symptoms either, passes it on to a chicken, and then the problems start.

Chris - And why is a chicken a problem?

John - We don't know that really. It could be because chickens are pressurised with the modern farming techniques.

Chris - What with having lots of them in a small space. I suppose that makes transmission very effective. But then how does it get into a person?

John - Well the hapless farmer comes along to admire his wonderful flock and notices that one or two of them are ill. A few days later, they're all dead. It's called wall to wall carpeting of feathers. He then realises what's happening. He calls in the vet who examines the beak and pokes a swab up their bottom. The vet is usually the first person to get in close, catch the virus and die.

Catherine - So we hear that flu is a problem in birds and in humans. What about other animals?

John - It's mainly this bird reservoir and humans. All other animals on this planet get flu. We know horses get it, whales get it. You name it and they have it, although obviously at the moment we are more interested in the human aspect than whales.

Chris - So why should this particular strain of bird flu be an issue? Why is it more problematic than the normal strains of flu that reach our shores?

John - Because this is an entirely new one. This has emerged from this reservoir and no-one has ever seen it before. No-one on this planet has any immunity to it. We're all relying on our snot basically, as that's all we've got, and of course these new drugs and maybe some new vaccines.

Chris - So when you say we've never seen this before you're saying that most of us, because we've come across flu in the past have a degree of underlying immunity to the virus. But because this one is so different, we have no protection. Our pre-existing exposure gives no protection.

John - Yes, we're very very vulnerable, and that's what the worry is.

Catherine - But can't they just make a vaccine for it?

John - You can stock up on antiviral drugs. The class of drugs that blocks the mushroom on the virus is a very powerful class of drugs, and I think we will be relying on those. But as for the vaccine, which will also be very important indeed, one has to make a choice. I think the choice to make is to go for the virus we've got at the moment and assume that it's not going to mutate too much. We can then make some vaccines and all relax in our beds.

Chris - Because there's some evidence that this particular strain has been in circulation for a little while before and there is a backdated or stored version of that that has been shown to be protective if it's turned into a vaccine.

John - Yes, and the most recent experiments in volunteers shows that you can get some protective immunity. You might need a lot of inactivated virus to do it, but in practice you can get something. So I think there's every reason now to press the button, make some more of this vaccine and relax a little bit.

It may shock some people, but your feet actually squirt about half a litre of sweat into your socks and shoes every single day. You also shed in the order of about 40 000 skin cells every minute or so from your body. Over a lifetime that adds up to a few stones in weight of dead skin. Now this is perfect bacterial food, so you have a combination of a warm, damp place with lots of food. This makes your feet a thriving emporium of bacteria and fungi. When these eat the skin in your shoes, they produce volatile substances that smell. It's these substances that come whiffing up to your nose. People who wear trainers a lot end up locking their feet in and let them stew. The way around it is either to use odour eaters or wear sandals, as this lets your feet ventilate. Alternatively, you can wear leather shoes, as this helps your feet breathe more naturally.

The shape of the plug has something to do with it, because you get a kind of whirlpool effect. The size of the whirlpool is affected by the size of the the plug hole. Some people believe that the direction of the whirlpool is down to the Coriolis Effect, the conservation of angular momentum which applies to moving things - like air and fluids - as the Earth turns in space. But simple calculations show that actually the Coriolis force is too small to account for the direction that water goes down the plughole, so the whirlpool produced when the plug comes out must be a product of the shape of the sink and the drain hole.

Actually, not a lot of people do. Most of the phlegm that you produce ends up in your stomach. On the way to your lungs, all of your airways are lined with a sticky substance called mucus. It's there to mop up things like bacteria, viruses and particles of dust and dirt from the air. The linings of your lungs have tiny thread-like projections on their that beat. They all beat in the same direction which creates a current which pushes the mucus out of your lungs and up to your throat. Now if you get a lot of mucus, sometimes you cough and it can come flying out of your mouth. But most of it goes down into your stomach. That's very important, because as it has all the nasty things you've breathed in locked up in it. These are carried down into your stomach where stomach acid kills all the bugs. What's left then goes into your intestines. In the walls of your intestines the dead bugs and dirt meet special patches called Peyer's patches, and that's where your immune system learns what's doing the rounds in the air around you, what sorts of things it has to mount an attack against, and what sorts of things it has to ignore. So normally you swallow most of your phlegm, but if you have excess production, coughing it up helps to get rid of it.

This is a reflex called the photic sneeze reflex and no-one's exactly sure what underlies it. We know that it's genetic and is passed on in families. About one person in four or one person in five is affected. People used to think that when you looked at the Sun, the bright light made your eyes water, the water ran down into your nose, tickled your nose and made you sneeze. This is not true because it happens too fast. What scientists think is that there's some sort of crossed wiring in the back of the brain where the size of your pupil is controlled, and that's what causes that to happen.

Standing on Jupiter would be like having a bus standing on your head, as you'd weigh so much. So the bones in your feet which are set up to withstand 50 kg of weight pushing through them, would now have to withstand 13 tonnes. I don't think even the nest hip replacement would be able to withstand that kind of load. So you would be as flat as a pancake.