According to an article at Science Daily children who receive the flu shot might have up to three times the risk of hospitalization for the flu. The article talks about a cohort study of influenza performed at the Mayo Clinic that looked at 263 children who were seen at the clinic with laboratory-confirmed influenza between 1996 and 2006. The study verified who had received the flu vaccine and who had not and determined that children who received the flu vaccine had three times the risk of hospitalization when compared to those who had not.
I have not been able to find the original source of the study but it was supposed to be presented at the 105th International Conference of the American Thoracic Society.
After reading this article I started to wonder at how well the flu shot works in general, so I went looking for some information. What I found made me wonder at why it is pushed so much.
First a little background - there are currently two styles of flu vaccines on the market now. The first is a the flu "shot" made from inactivated (killed) virus that you get via an injection at a doctors office or some other clinic. The second is a nasal spray that contains an attenuated (live weakened) viruses. This second form is a more recent development that is not as widespread yet.
I am going to be talking about the first form only - the traditional flu shot.
So lets start with the first problem - the flu shot is one of the few types of vaccinations that still contains thimerosal (ie mercury). If you don't know why that could be a problem just google autism and mercury and prepare to wade into a holy war.
The short version is that this preservative isn't a good idea and while there are no "proven" health problems associated with it there is no reason for it to still be there. The good news is that thimerosal free versions are available but you have to ask for them.
The second problem is that the flu shot isn't that good at preventing the flu. According to the (most likely over-optimistic) CDC the flu vaccine can prevent 66% of cases of influenza in young children. But the effectiveness of the shot can vary from year to year based on how well the the shot is matched to the strains of flu that are active that year.
I also looked for published research detailing how well the flu vaccine worked in children and found a mixed bag. Some research agrees with the 66% that the CDC says while some does not. I was particularly struck by this meta study published in Lancet in 2005 that found that the effectiveness of the vaccine in children older than 2 was about 38% but in children under two performed no better than a placebo.
So at worst the shot may have no little or no real effect and may lead to a greater risk of hospitalization but at best could have a better than 66% chance of preventing the flu.
As I have written about before I am a little leery about this shot because the one time that my twins received this shot they seemed to develop the flu shortly afterwards closing followed by their regression into autism.
So, is the flu shot a good idea for kids? I think the answer is a definite maybe.