This is a section of a long article answering FAQ about the swine flu from Science Based Medicine. I will try and post other parts of the article throughout the week or you can go to the following website to read more. http://www.sciencebasedmedicine.org/?p=1455 A NEW AND UNTESTED VACCINE IS BEING TESTED ON THE AMERICAN PUBLIC Author Mark Crislip It is new, and it is untested. As the flu vaccine is every year. Or, more appropriately, it’s the same old flu with the same old vaccine. Keeping with the car metaphor used above, we are not seeing a new form of transportation, just a new model of the same old car. It takes about 9 month to make a flu vaccine. The first three months or so are spent deciding on what strains are to be included and if there are representative strains that grow well for vaccine production. After the strains are chosen, it takes about 6 months to grow up large quantities of vaccine in chicken eggs. Each dose of vaccine comes from one egg. And there is only one chicken that can make all those eggs and she gets tired. Then the vaccine is purified to just the neuraminidase and hemagglutinin proteins that are in the vaccine. The fast track we have now is due to a lucky confluence of factors. First, industry had just finished making this years seasonal flu vaccine so they had the unexpected capacity to churn out vaccine. But more importantly they had a jump on picking the strain. They did not have to guess which strains to include, they knew it was H1N1, so that gave them a three month head start. That is the main reason we have the H1N1 vaccine in record time. The process of growing the influenza and purifying it is preceding at the usual pace. We we just lucky that we were able to know the exact strain and it occurred when we had the capacity to make extra vaccine. So while it is being produced at a faster rate, it is not because they are skimping on the steps in the production, it is because we got lucky. As an aside, I am told that the strain they are using for the vaccine is not the best at growing in chicken eggs and is a reason the vaccine will not be ready until mid October. Evidently it does not grow as robustly in chicken eggs as they would like. As far as anyone can tell, they is nothing special about the H1N1 strain (and they have looked at it closely) to suggest there is anything unique about it except that it is immunologically new (at least since 1950’s, when the H1N1 progenitors were last seen in humans). This H1N1 in part can be traced back to the 1918 strain and explains why those over 60 have a decreased death rate rather than the usual increased mortality from influenza: old people have cross reacting antibodies to the strain that is protective. This strain is only new to people born since about 1950, which is billions of people at risk with no immunity. But as far as virulence and antigenicity, it is the same old influenza, re-assorting its RNA to come up with new strains as it has always done and will continue to do as long as there are people pigs and birds around to get influenza. H1N1 is fundamentally the same as any other flu that we have been making vaccine against for as long was he have been making vaccine. It is undergoing the same testing we have used every year and there is no reason to suspect that we should be doing otherwise. I am nervous. Fall is coming. If H1N1 comes again (and pandemics have swept through the world several times in one year, the 1919 flu may have had three peaks) before the vaccine, we could be in a world of hurt. Not a lot of deaths by US standards (we lose that 30,000 or so to guns or car accidents every year, just like flu). I have spent a career watching people suffer and occasionally die of potentially preventable illnesses. I am not a fan of death by infection. I hope the vaccine is widely available and widely used so that people live to die at a later date.