As a new flu season arrives, older Americans are facing an increased risk of dying from the virus. An AARP Bulletin analysis of government data reveals that deaths attributed to the flu among those 65 and older have spiked in recent years. More than 12,000 people ages 65 and older died from the disease during the last flu season (starting Oct. 1, 2017). That is more than double the death toll of the 2016-17 flu season and six times the number from 2015-16, the Bulletin found when analyzing data that the U.S. Centers for Disease Control and Prevention (CDC) maintains on death certificates.
In addition to a large death toll in 2017-18, the number of flu-related hospitalizations of those 65 and older “was higher than we’ve seen in any other previous year,” CDC spokeswoman Kristen Nordlund says.
And even that death-certificate death toll may be understated. Recent news reports have shown a CDC estimate of 80,000 total flu deaths in the U.S. in the past year, based on a different method of statistical analysis that tries to assess where flu may have been a factor in a person’s death even if it isn’t listed on a death certificate. More precise figures, in which flu is specifically listed as a cause of death, shows 15,541 fatalities from Oct. 1, 2017, through early September (the most recent report available). Nearly 80 percent of those who died from flu were 65 or older — 12,230 — a significant increase over recent years.
This spike in flu deaths seems to negate what should be a success story. People age 65 and older are much better than others at getting annual flu shots. In 2017, 69 percent of seniors got a flu shot, while the vaccination rate was 46 percent for people ages 50 to 64, 33 percent for ages 18 to 49 and 48 percent for those 17 and younger. The flu accounts for about 5 percent of all winter deaths among older Americans, says Michael Jackson, a vaccine and infectious-disease researcher for Kaiser Permanente.
“This is a wake-up call for the world,” says Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. “For many decades we thought the flu vaccine worked better than it did. People always thought we had the vaccine we need.”
Better vaccines needed
In late February, amid soaring numbers of flu deaths and pressure from Congress, the National Institute of Allergy and Infectious Diseases (NIAID) announced a major initiative to develop a new, more effective vaccine. A so-called universal flu vaccine would protect people against all strains of flu instead of just a few and would be needed only once every few years instead of every year. The announcement came after a four-week stretch that saw the flu kill older Americans at a rate of 169 people a day, or seven people per hour, the Bulletin found.
Weeks before the NIAID announcement, Sen. Edward Markey (D-Mass.) called federal spending on new flu vaccines “simply not enough” and proposed $1 billion over five years for research. In March, Congress allocated $100 million for 2018-19, an increase from the $64 million the government spent in 2017-18. “We are far, far short of what’s necessary to do the basic research to understand how to develop a universal or game-changing flu vaccine,” Osterholm says. “We need to spend $1 billion a year for at least the next five to seven years.”
Markey says the $100 million in funding, while short of the $200 million he sought for next year, still “supercharges federal efforts” to improve flu vaccines.
The flu's challenges
The development of effective flu vaccines has been a challenge since the shots were first administered in the 1940s to protect U.S. soldiers, a group that had suffered a huge number of flu deaths during World War I.
In its best years, the flu vaccine is 60 percent effective, meaning people who get a flu shot are 60 percent less likely to get the disease than people who do not get a shot. In its worst years, the vaccine is only 10 percent effective. The CDC projected in February that the 2017-18 vaccine was about 36 percent effective, meaning that people who get the shot were 36 percent less likely to contract the flu. The CDC has not assessed the 2018-19 vaccine. But a study by Rice University predicts that the flu vaccine will likely have the same reduced efficacy as the vaccines used in the previous two years.
The shortcomings occur because the flu virus has many forms, or strains; scientists must try to predict the strain that will dominate in an upcoming season for vaccine development. This is different for viruses such as measles, which don’t change; childhood vaccinations protect people for life.
“The flu virus is constantly changing. It’s a moving target,” CDC epidemiologist Alicia Budd says. “Each year you’re basically creating a brand-new product.”
As they are grown in labs, the viruses used in the vaccines are matched to the expected flu strain. But during growth, their genetic makeup often changes, which can make them less effective, Budd says. “There’s a lot more work that needs to be done to try to understand exactly what these genetic changes are and what the subsequent implications might be,” she says.
In people 65 and older, the problem is heightened because their immune systems have become inherently weaker due to age. That makes them even less responsive to vaccines.
In 2012-13 the flu vaccine was only 11 percent effective for seniors, even though it was 49 percent effective for the overall population, according to a study published in the Journal of Infectious Diseases. The vaccine in 2010-11 was 60 percent effective in the overall population but only 38 percent effective for seniors, another CDC-funded report shows.
A vaccine for older Americans
For years, researchers vastly overestimated the flu vaccine’s effectiveness on people age 65 and older. In assembling study groups, researchers included too many healthy individuals who were generally more resistant to the flu. Scientists discovered the errors in the mid-2000s and began designing more accurate studies. But the overestimations minimized any urgency to improve vaccines for the 65-plus population, says Lone Simonsen, an infectious disease expert at George Washington University, who helped debunk the earlier studies.
“If you thought the vaccine worked so well in the elderly, you wouldn’t question that the existing vaccines weren’t good enough,” Simonsen says. “Our research led to better formulations for seniors, and those are used now.”
A high-dose flu vaccine for individuals 65 and older, Fluzone High-Dose, has been shown to be more effective, according to the CDC. But some health clinics have been slow to offer it because it is new and unfamiliar.
The Washington State Vaccine Advisory Committee recommended in August 2017 that health care providers in the state offer seniors the high-dose vaccine or an adjuvanted vaccine that has an added ingredient to boost the body’s immune response. It was the first time the committee had made such a recommendation, says Kathy Lofy, the state health officer in Washington.
“We had been hearing after the high-dose vaccine came out that a lot of clinics weren’t even buying it,” Lofy says. “Some clinics were just deciding to stick with the standard-dose vaccine. The high-dose vaccine was new, and initially there wasn’t a lot of data about it.”
Lofy says she does not know how many clinics offered the high-dose vaccine in 2017-18 or how many people received it.
The CDC urges everyone who is at least 6 months old to get an annual flu shot and says older people and infants are at particular risk for the flu. Although the vaccine may provide only limited protection, health officials say it is better than nothing. Says Budd, the CDC epidemiologist: “While we have an imperfect vaccine, it still ends up preventing a significant amount of illness.”