For Your Next Flu Vaccine, Will It Be Shot, or Nasal Spray?

For Your Next Flu Vaccine, Will It Be Shot, or Nasal Spray?

The virus is inactivated in the shot, and live in the nasal spray—which makes a difference for children, asthma patients and others.

From the Wall Street Journal

Public-health officials recommend that everyone over the age of 6 months get vaccinated against flu. Alicia Fry, a medical officer in the influenza division at the Centers for Disease Control and Prevention, explains which type of vaccine—a flu shot or a nasal spray—works better and when.

—Heidi Mitchell

Not to Be Fooled With

Many people consider the flu a mere annoyance, but it causes thousands of deaths and even more hospitalizations each year, mainly among older people and young children. “The flu causes a spectrum of illness. It’s not always just the sniffles,” Dr. Fry says. Still, despite public-health urgings to get vaccinated, only about half of all Americans actually do.

Flu shots contain inactivated influenza virus that puts the body’s immune system on guard for when a real virus comes along. By contrast, the spray contains live viruses, albeit weakened ones. It is known as live attenuated influenza vaccine, or LAIV, and is sold in the U.S. under the brand name FluMist. Shots are much more widely available than the spray.

Best for Children

The CDC released data in August following years of study comparing flu shots and nasal sprays. The conclusion: In children ages 2 through 8, the nasal spray was more effective in preventing flu. The CDC this flu season began recommending the spray for healthy children in that age group. But the agency emphasized that if the spray isn’t available, children should get a shot rather than delay being vaccinated.

“FluMist is cold-adapted, so it can replicate in your nose. But as soon as it goes anywhere else warmer in your body, it dies,” explains Dr. Fry. “We think that the live vaccine acts like a regular flu infection, so you get a more robust immune reaction to it,” even in viruses that evolve and diverge from the original strain, she says.

Feeling Fluish

Some people complain about feeling a little fluish after the mist is administered, which means the vaccine is working, Dr. Fry says. Although others might say they feel under the weather after a shot, getting flu from it isn’t possible. “The shot is an inactivated virus—you cannot get the flu from the shot,” Dr. Fry says.

Not everyone should have the nasal-spray vaccination. It is approved only for people between the ages of 2 and 49 (the flu shot, by contrast, is approved for use in most people over the age of 6 months). Among various restrictions: People on some antiviral drugs and those with a compromised immune system shouldn’t get the spray. And people with a history of asthma might need to avoid it.

People allergic to eggs also shouldn’t get a nasal-spray vaccine, says Dr. Fry. “If you’re an adult, there is a new FluBlok vaccine shot that has no egg. But if you are a child with an egg allergy, you are recommended to get the regular flu shot from a physician who is experienced with allergic reactions. And you need to stick around for 30 minutes of observation,” she says.

Possible Glitch

Recent data from the U.S. Flu Vaccine Effectiveness Network showed a possible glitch with the nasal spray: It didn’t work in last year’s flu season against H1N1, one of the four strains of flu virus contained in both shot and spray vaccines. Surveillance data doesn’t show very much H1N1 circulating this year, and the CDC hopes the flu strain won’t be a big problem, Dr. Fry says.

Despite the H1N1 issue, the CDC still recommends a nasal-spray vaccine for healthy children ages 2 to 8 “since it is more effective even against flu strains that veer from the most common ones dominating this year,” Dr. Fry says. “We hope that we can fix this H1N1 vaccine problem for next year,” she says.

Dr. Fry says the most important thing about flu vaccination is that people get it, regardless of whether it’s a shot or a spray. Since it takes two weeks to take effect, Dr. Fry and her colleagues are urging people to get vaccinated now. “We already have a little bit of flu circulating, and the biggest peaks typically occur in end of December through February. It’s important to get vaccinated before flu activity really starts to circulate.”