Effectiveness Depends on Targeting the Right Strain
The way the Centers for Disease Control and Prevention (CDC) determine what type of vaccine to use each year is by predicting in April which flu virus will be circulating during the next flu season. The reason they do this is because it typically takes about six months to make the vaccine. Last year’s flu vaccine was the same as the year before because in April, the major circulating strain of flu was the same as the previous year. Things changed in September, however, when a different flu virus began to circulate, so the vaccine we had on hand turned out to be much less effective than the 70-80 percent effectiveness the flu vaccine normally provides.
This Year’s Vaccine Is a Good MatchIt’s difficult to predict the future of viruses from year to year, but the good news is that they CDC can normally tell what will circulate here in the Northern Hemisphere by looking at what has circulated during the winter in the Southern Hemisphere. So far, it looks like this year’s vaccine is going to be a good match. The flu virus hasn’t changed very much since April when they made the decision on what to include in the new vaccine, so it’s likely to be it’s usually 70-80 percent effective. There are several vaccine delivery options available.
- Intradermal vaccines are shorter needles that administer a smaller amount of the vaccine just under the skin. Those who are wary of needles may be more at ease with this option.
- The high-dose vaccine is available for people older than 65. This option is specifically for older patients because their immune systems are more easily compromised and a bout with the flu for an older person may be more difficult to fight off than in a younger patient. The high-dose vaccine actually has four times as much vaccine than the regular vaccine and it produces a better immune response.
- The regular flu shot is also available.
Protect Yourself and Others
In short – everyone needs to be vaccinated if you are physically able to receive a vaccine. The most at-risk patients are people older than 65 and children younger than 2 because they have weaker immune systems. Children younger than 6 months are not able to be immunized for the flu, so it is crucially important for those around them to get vaccinated in order to keep infants safe. Even in cases like last year’s vaccine, which wasn’t considered a good match, even a poorly-matched flu vaccine is better than no vaccine at all. It takes two weeks for the vaccine to become fully effective, so the time to get vaccinated is now before this year’s flu season hits full force.
Dr. Melanie Mouzoon, M.D., F.A.A.P., is a board-certified pediatrician, pediatric hospitalist and managing physician for Immunization Practices and Travel Medicine at Kelsey-Seybold.