By now we've all been made aware of the potential apocalypse that is the H1N1 strain of influenza running around right now, but a recent study showed that most people have no idea 'why' they should be wary of it, they just 'know' they should. So, what is it about this particular virus that makes it so news worthy?
H1N1 (also called the 'swine flu') is a particular strain of a type of the influenza virus called 'Influenza A'. There are other influenzas as well, but this discussion will focus solely on the 'A' variety. The 'H1N1' moniker comes from the way scientists classify these viruses.
For simplicity's sake, just imagine these viruses look like a pin cushion, pins and all. The viral 'DNA' (influenza actually uses RNA, but that's irrelevant in this discussion; suffice it to say that for our purposes they're the same thing) is contained inside the actual cushion (more on that later), and the 'pins' on the outside are actually protein receptors used by the virus to gain entry into the host cell and do a few other things as well. These protein receptors are called hemagglutinin (where the 'H' comes from) and neuraminidase (where the 'N' comes from). The numbers after the H and N refer to the ratio of these receptors to each other, so 'H1N1' means that for every one H, there is one N. The ratios of these proteins vary from virus to virus and over time you will see a whole host of numbers, however it is not the 'H1N1' that makes this virus a potential nightmare.
The thing about this virus we need to worry about is the 'DNA' inside the virus. The fact that it comes from a pig isn't anything for us to worry about. If it was 'just' a swine flu, our immune system would be able to easily ward it off and we could all go about our merry ways. The problem is that it isn't 'just' a swine flue. No, this virus has the hallmarks of an avian, or bird flu as well. Remember the bird flu we were all freaking out about years ago? The bird flu itself has the potential to be scary, because the viruses that infect birds use tricks that mammalian immune systems are not equipped to ward off, so if we catch it, there is nothing we could do about it. It would be like if Ghengis Khan and the Mongols from way back when could have invaded Brazil, and the Brazilians only hopes of warding off the invaders was to reason with them. Unfortunately, the Brazilians and Mongols don't speak the same languages, so any hope of meaningful negotiations if futile.
Fortunately for us, viruses that infect birds do not possess the right tools to get into our cells, so we're safe from them...But that's where the pigs come in. You see, pigs can be infected by both bird viruses and human viruses. Sometimes, a human virus and a bird virus end up infecting the same cell in a pig, and all of the sudden an unholy marriage of viruses happen, the result of which is a frankensteined virus containing parts of the bird virus we cannot fight off, and parts of the human virus that allow that virus to enter human cells. This is what happened in the 1918 'Spanish flu' that was responsible for the deaths of millions of people, and is in fact where the H1N1 virus of today came from as well.
However, just because the virus contains elements of avian, swine, and human viruses does not automatically make it a global killer. Each of those pieces needs to be exactly correct, and as of right now, that is not the case. The worrisome part is that the virus could mutate (viruses mutate extremely quickly and often) to a form that would be very infectious and very deadly. However, given the time that has passed since it began, this is highly unlikely and does not pose any sort of imminent threat.
That being the case, please feel free to go about your lives knowing that your fears would be better used to worry about an asteroid or killer quake hitting your area right now than about the swine flu rearing its ugly head and killing us all.