Texas Medical Center

New Flu Vaccine Guards Against Four Strains



The kids are back in school, the Houston Texans are back on the gridiron, and stores everywhere are stockpiling cases of Halloween candy. We can check all those “It Must Be Fall” signs off our list. Can we check one more? Have you had your flu shot?

Federal health officials recommend a yearly flu vaccine for nearly everyone, starting at 6 months of age.


Robert Robbins, M.D.,
Texas Medical Center
president/CEO and
Texas Medical Center
News publisher

October is an ideal time to be immunized against influenza. It takes at least two weeks after immunization for protection to kick in, so getting vaccinated now buys you time to build up a strong immunity before flu season arrives.

For the first time, the Federal Drug Administration this year has approved the use of quadrivalent vaccines which guard against four strains of flu rather than the usual three. The quadrivalent vaccines protect against two strains of Type A and two strains of Type B flu, whereas the more common trivalent vaccines that have been around for more than 30 years offer protection against two strains of Type A flu and just one of Type B.

Dr. Catherine Troisi, director of public health practice at the City of Houston Department of Health and Human Services and an associate professor at the University of Texas School of Public Health at Houston, says the trivalent vaccines are still more prevalent. The quadrivalent vaccines are so new that they’ll make up only a fraction of the nation’s supply of flu vaccine, so if you want one, get your flu shot early.

The FDA recommends quadrivalent vaccines for young children because kids tend to catch the newly added strain more often, and for senior citizens who may be more susceptible to flu viruses and have less ability to fight infection.

Not all doctors have the new vaccine, so Troisi says if you can’t get the more powerful vaccine, take the trivalent instead.

The Centers for Disease Control doesn’t recommend one vaccine variety over another, and the American Academy of Pediatrics says the trivalent and quadrivalent vaccines are both fine. The important thing is to get vaccinated.

This year, there’s also a vaccine for people who have not taken flu shots in the past because they have egg allergies. This recombinant influenza vaccine, marketed as FluBlok, is made without the use of eggs. The FDA recommends this vaccine for people ages 18 to 49 years of age. Again, the availability could be limited, so check with your doctor.

And for those who prefer a nasal spray vaccine, all of the nasal spray flu vaccines sold in the U.S. this year will be the four-strain variety, and will be marketed under the name FluMist Quadrivalent. The nasal vaccine is for healthy people ages 2 to 49 who are not pregnant.

Finally, those who don’t qualify for the painless nasal vaccine but who are scared of needles have an alternative. Fluzone Intradermal is little more than a skin prick instead of a needle into the muscle. It’s available for 18- to 64-year-olds, and protects against the usual three strains.

For the 65-and-over crowd, manufacturers are offering a high-dose trivalent vaccine named Fluzone High-Dose. This revved-up vaccine protects against the traditional three strains of the flu, but it quadruples the standard vaccine dose to strengthen age-weakened immune systems.

The flu season is unpredictable. We don’t know when it is going to arrive and how severe it will be when it gets here. Each year’s vaccine is the medical profession’s best guess at what viruses will be circulating. Yet we know that even if we don’t nail the exact formula, a person receiving a flu shot is less likely to have a bad case of the flu, or die from it.

It has never been as easy as it is this year to protect yourself and others against the flu. Just get your shot.