The Centers for Disease Control and Prevention announced yesterday (Dec. 4) that this year’s flu vaccine may be less protective than expected. In his press announcement, CDC Director Tom Frieden stated, “Though we cannot predict what will happen the rest of this flu season, it’s possible we may have a season that’s more severe than most.”
Why Is This?
Each year a new flu vaccine is produced to protect against the strains of flu virus most likely to cause illness in the coming flu season. Flu shots typically protect against 3 or 4 different flu viruses. (At Sparks & Favor, we offer the quadrivalent vaccine—protective against 4 flu strains). Production of flu vaccine takes about four months, and distribution begins in the fall. All of this year’s vaccines were designed to protect against one strain of H1N1 (type A) and one strain of H3N2 (type A) virus, as well as one or two strains of type B virus. Flu seasons dominated by type A virus are generally more severe.
If the flu shot is a “good match” for the season’s flu viruses, it typically reduces one’s flu risk by 50 to 70%. And those who get the flu despite having received the shot are likely to have a milder illness. Unfortunately, flu viruses are constantly changing by a process called mutation. In September, researchers detected that a new strain of H3N2 virus had become more common. The 2014-15 shot was not designed to protect against this new strain. At this point in the season, it is not possible to produce and distribute a revised vaccine.
For the week of Nov. 22nd, the CDC determined that about half of flu cases tested were caused by the new viral strain. If the trend continues, this year’s flu shot will likely be less effective than the 50 to 70% risk reduction we hope for.
What do we recommend to our patients?
- You should absolutely still get your annual flu shot! Despite the disappointing news, the vaccine still protects against a significant portion of this year’s flu risk. Furthermore, it is possible that the vaccine may provide some cross-protection against the new virus—reducing the risk of severe flu outcomes like hospitalization or death.
- Protect yourself and others. Regular thorough hand washing (15 sec.) reduces your risk for contagious respiratory and stomach viruses. And, of course, stay at home if you are ill.
- If you become ill with flu-like symptoms, call us! Flu symptoms typically include fever, body aches, cough, sore throat, and fatigue. The flu often comes on more suddenly and severely than a typical cold. If the flu is likely, we will help you determine whether immediate medical treatment is necessary. In most cases, we will also prescribe an anti-viral medication like Tamiflu. These medications shorten the duration of the illness by about a day on average and also reduce the severity of your symptoms. They are most effective if you begin taking them within the first 1 to 2 days.
- Especially, call us if you are pregnant!
- Antibiotics do not fight the flu. Antibiotics have no effect against viruses. They are only used in cases where the flu is complicated by a bacterial illness.
The flu is not just a bad cold—it is a serious illness! It causes thousand of hospitalizations and deaths each year. Pregnant women, the elderly, and persons with other medical conditions have a greater risk of serious flu outcomes. It is possible—though too early to know—that this year will be worse than average. We hope you will follow these tips to protect yourself and your family.