i was watching the news this morning and i guess the bird flu has now hit in sweden and some other places throughout europe. well, as the resident virologist, i better get to edumacating! i’ll try to keep it accessible to everybody and speak in term we can all understand.
so! the avian flu is a virus related to human influenza. it’s generally not too serious and infects only certain organs, like the lungs. this is because the virus recognizes and binds to the molecule sialic acid, which is commanly found on many cell types in the body, but requires additional interaction with the cell membrane to infect the cell. ie: it can bind to most cells in the body, but only certain cells will cause the virus to infect it.
here’s where an analogy come in handy. let’s say mr. t is walking down the street. now, he might bump into all sorts of people, but depending on the type of chains he’s wearing, certain people will stop and talk to him (ok, i realize this is a little ridiculous. REGARDLESS of the chains around his neck, all the people of the world love and would talk to mr. t on the street, but bear with me here. this is science). so, like a rosary for the catholics, star of david or something for the israelites, dollar sign for americans, etc. now! let’s say, there’s a little change to his chains and now everyone feels the need to talk to him. this would be like the H5N1 strain (designating a mutation in the viral protein that binds sialic acid), which allows the virus to infect most cell types in the body. so, assuming/hoping that mr.t could replicate himself whenever he starts a conversation with someone (much like a virus replicates itself in it’s host cell), there would soon a whole lot of conversations and very few people getting to work or buying hot dogs or whatever normal people do. i.e: the mortality rate (number of infected individuals who are killed by the virus) goes WAYYY up.
now, so far, mr.t can only talk to people (or in the avian flu version, only birds can be infected). but what if giants walked the earth. obviously, they are too large to have a conversation with a teeny-tiny mr. t. but if enough mr.t’s where grouped together, they might be able to talk loud enough for a giant to hear. (this would be equivalent to a poultry worker who is around ALOT of infected bird feces, which contains viruses from infected birds, and will get sick). this poor giant wouldn’t stand a chance (because he is also a fool).
now! the last, and most worrisome part (im not 100% sure on this part, but i will ask my viro prof about this). the avain flu which infected a human, will be able to replicate itself (i am pretty sure) but will not produce the ridiculously high amounts of virus needed to infect another human being (because, these viruses are not designed to infect humans, so you’d really have to get blasted with alot of viruses to get sick, i.e.: our poor poultry worker). but, if the H5N1 strain were to mutate again to be able to spread from human to human, we would potentially have a global health threat, similar to the spanish flu of 1918, which killed about 100million people world-wide (and this number keeps being increased with new information) in about 8 months. to put this into perspective, AIDS has killed like 30million in 25 years.
hope that helped.