It is time once again for my annual urging for people to get their flu shot. You can get a flu shot in most cities starting October 1. Enter your ZIP code on this site to find the location of the nearest place for you to get your vaccination.

Last year there was a bad shortage of flu vaccinations, but we were lucky that it was a mild flu season. This year we might not be so lucky. Worldwide flu activity reports won’t be published for the 2005-2006 flu season until next week.

I have also been keeping my eye on the extremely deadly bird flu (avian influenza A (H5N1)). If a person gets infected with this flu, there is about a 65% chance that person will die.

There are a few reasons why this strain of flu is so deadly, but the biggest reason is that this strain looks completely different to our immune system than any other strain. Our immune systems can mount a fairly good defense to strains of flu that are derivatives or existing strains, but when they get infected with H5N1 the normal defense mechanisms don't work.

Right now almost all human cases are from bird-to-human contact. There has only been 1 and maybe 2 cases of human-to-human transmission. The disease doesn't have the ability to effectively be transmitted from human-to-human, but scientists think that it is "when" not "if" that will happen. It could be a couple weeks or a couple years.

There are no vaccines for this now, and there is a drug they think will save your life if you get infected, but it is in extremely short supply, and I don't think it is 100% effective. When it does mutate to a form that can be transmitted from human to human they think it will spread very rapidly and globally.

Even though the current flu vaccines will not protect against the bird flu, I think it is another important reason to get the vaccine. If the bird flu starts to spread, other strains of the flu will spread faster than normal because of people's weakened immune systems. Therefore being immune from the current strains of flu could save your life if/when bird flu starts to spread.