A high fever, night sweats, periodic chills, and bouts of delirium can seem like pure hell. My recent bout with this year’s flu (influenza virus) had completely knocked me out of commission. Like so many others that were infected this year it was a long road to recovery. It has been more than a week since I came down with the flu and I am just now finally feeling like I am back on my feet. Through the whole ordeal I had one lingering question: I got my flu shot this year so why did I still get so sick?
Just before I came down with the flu I remember hearing a story on NPR (link here) about how ineffective this year’s flu shot has been. The reporter noted that the vaccine has been 56% effective for preventing all strains of the flu virus in the general population but it has been only 27% effective in preventing those over 65 years old from getting the flu. What was even more concerning is that the CDC was reporting that this year’s vaccine has been only 9% effective for the elderly in fighting the most common strain of the flu. Can that be right – only 9% effective? What else in our lives would we willingly pay for if we knew that it was only 9% effective?
I have to admit that I do get a little annoyed when I my annual flu shot “fails” and I still catch the flu virus. It seems somewhat fraudulent even though I know that getting the flu shot isn’t supposed to eliminate your chances of getting the flu. Instead we get a weakened strain of the virus from the shot which is supposed to then trigger a stronger immune response if we do get the full blown virus. The goal of the entire process is to lessen the intensity of symptoms and speed the recovery period. The reality is that the flu shot is simply a game of percentages with no guarantees. But this realization doesn’t make it any easier when we’re on our back aching for several days with a high-grade fever.
The complexity of the flu shot business is not unlike any other complex business decision. Each year thousands of doctors and scientists are involved in reporting and researching which will be the likely flu strains for the year. They then spend enormous sums in an attempt to create a vaccine for those virus strains and to distribute those vaccines to doctors and pharmacies across the country. There are hundreds if not thousands of variables that are involved that will determine the success or failure of each year’s vaccine. Are they targeting the correct virus strains, is the vaccine strong enough to elicit an immune response, has the virus mutated along the way, or is there possibly an entirely new strain of the flu virus that we have never seen before (i.e. the 2009 H1N1 flu virus)?
All of this complexity in the process is what drives the very low effective rate for the vaccine. The question then becomes, is a vaccine with a low effective rate better than no vaccine at all? The CDC suggests “Yes.” Because of the low risks associate with the vaccine they suggest that it is better for people to get the annual flu shot even if it doesn’t prevent them from getting the flu. This is the dilemma of the world we live in. We want clear answers but medicine is still a long ways away from the perfect clarity that we seek (see my recent post on Doctor Mistakes). It is important to note that because of this year’s low effect rate for the flu shot the CDC is going to reexamine how to best protect seniors 65 and older for next year’s vaccine. Like every organization should, they are trying to learning from their past shortcomings.
Food for thought:
Sources:
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