Let’s get one thing straight:
All flu is bird flu.Â Practically all new strains of influenza originate in China because that’s where the two species that get flu the most — pigs and ducks — live by the millions in close proximity.Â Every time a duck gets the flu from a pig, or pig from a duck, the flu virus changes slightly; and when one of these infects a farm worker, the new strain crosses over into the human population.Â It is by monitoring influenza emergence in China that each year’s flu vaccine is prepared.Â So far, over the last 30 years or so, predictions have been very accurate, with only one recent strain mutating somewhat on the way to the US — with the vaccine retaining partial efficacy.Â Still, of those not getting the vaccine, tens of thousands still die each year from complications of influenza.
So what’s the “bird flu” that’s in the news?Â Actually it is a strain of flu, known as H5N1, that HARDLY EVER affects anyone BUT birds.Â Mammalian immune system seems to stop it before it causes any disease, most of the time. That’s the good news.
The bad news is,Â people who DO catch “bird flu” mount such an overwhelming immune response against the virus that their own immune system destroys their lungs in an attempt to eradicate the virus.Â This is nothing new in infectious disease — this is how, for example, meningococcal meningitis does its damage (and we do have a vaccine for that, recommended before college and mandatory in the military).Â What is unusual is the amount of attention it generates, relative to the harm it actually causes.
Worldwide annual human mortality from bird flu is actualy far below annual human death toll from chickenpox, for example, to say nothing of “real” flu, or of any of the truly dangerous diseases.Â The great influenza pandemic of 1918 that killed millions appears to have been H5N1 also, but as human-to-human transmission was common, it was not, by definition, “bird flu”.Â In the meantime, before “bird flu” vaccine is available, it is getting the equivalent of a billion-dollar marketing campaign, and I foresee a mad rush to get vaccinated for bird flu — by people who had in the past turned down the more important immunizations.Â You could call bird flu the ultimate celebrity disease — it is famous for being famous.
As for worrying about bird flu — fasten your seat belts, quit smoking, and get REAL flu vaccine.Â Then, maybe, bird flu will make it into the Top 100 Things to Worry About.Â Oh, and don’t forget to have a good laugh.Â It extends life.Â Really.