So a recent press release from the CDC has gotten some attention in the media. Here is the link:
For anyone not already familiar with it’s contents, the highlight for many was that antigenic drift (mutations) in the flu virus has resulted in many cases of flu detected so far this year being different from those contained in the vaccine, rendering it less effective. Additionally, these particular strains (H3N2) tend to be dominant during some of the more severe flu seasons of the recent past. All of which is, needless to say, very disappointing.
Several things to keep in mind here:
First, there are usually several strains of flu in circulation every year, and this year is no different. The flu vaccine we distributed in the office this fall should be effective against 4 of them. While the early H3N2 strain has seen some significant drift, the H1N1 and B strains contained in the vaccine have not, meaning the vaccine should be very effective in those cases.
Second, in past seasons with significant drift, the vaccine has still been very helpful, providing protection in the 37-42% range, with less severe infections and fewer complications. Not great, perhaps, but a significant benefit, particularly if we are expecting a bad season.
Third, there are still very few flu cases nationwide. Strains that are less common now can become more common later in the season.
Creating a flu vaccine every year is a daunting challenge. A committee of experts, using the best available data, has to select which strains to include in the vaccine many months prior to its manufacture and distribution. Viruses can change quickly during that time. The annual vaccine is essentially a prediction for the season, and some seasons are better than others. I am frankly amazed at how often they get it right, but even when they are wrong, the vaccine has significant benefits for those who receive it and for the people who come in contact with them.
The bottom line is this: If your child got a flu vaccine this season, in my opinion that is still a very good thing. In past years, 90% of pediatric flu fatalities occurred in unvaccinated children. And, for anyone who would still like a flu vaccine despite all this disappointing news, we still have plenty available.
Just call the office.