A year after one of the most severe flu seasons in decades, infectious disease experts are again urging people to get flu shots.
Influenza is unpredictable, but even in a mild flu year, thousands of Americans die directly from the disease or from complications like pneumonia, according to health authorities.
Like automotive seatbelts, which reduce both injuries and fatalities on the road, flu vaccinations prevent many cases of flu and make others less severe.
Unlike seatbelts, however, flu shots also help protect people around us, medical experts say. By blocking influenza’s spread, they also make it less likely that we will infect loved ones and neighbors, grandchildren and elderly parents.
Cases of influenza are already being seen locally, according to Jake Scott, an infectious disease physician with Stanford-ValleyCare Medical Center in Pleasanton.
Vaccine is available, the flu season is in its early stages, and this is the best time to be vaccinated, Scott said.
His view conforms to the recommendations of the Centers for Disease Control and the American Association of Pediatrics, which would like people to get their flu shots by the end of this month.
Jonathan Blum, an infectious disease expert with Kaiser Permanente, gives the same advice: get your flu shot now.
Last year, more than 80,000 Americans died from the flu, according to the CDC. The number is an estimate, since there is no legal requirement that flu deaths be reported to the CDC.
At least 180 children died, an exceptionally high number known to be exceeded only in global pandemic years when a new influenza strain appears and few have immunity.
That is a statistic that Scott, the father of two young children, finds particularly troubling. Pediatric flu deaths are largely preventable, he said. The CDC reports that 80% of the children who died from influenza last year did not have a flu shot.
At the other end of the age spectrum, more than 12,000 Americans 65 and older died of the flu last year, according to the AARP, which pays close attention to issues involving the elderly.
“That is more than double the death toll of the 2016-17 flu season and six times the number from 2015-16,” AARP reported in its October Bulletin.
A high death rate occurred even though the elderly are more likely to get their annual flu shots than are other age groups, according to AARP.
The elderly are generally more frail, less able to stand up to the stresses that a serious infection brings. Scott noted that “fallout from the inflammatory storm caused by the flu” can lead to “increased risk for stroke and heart attack.”
The elderly are also known to have less responsive immune systems. For many years, according to the AARP, flu vaccines were formulated based on studies of younger patients with stronger immune systems. Standard vaccines often did not stimulate the immune systems of older patients enough to prevent the flu.
A few years ago, however, researchers developed and clinics began to administer a high dose vaccine with four times more antigen than standard vaccines. (Antigens are the part of the vaccine that triggers the immune response.)
These are thought to be more effective for the elderly.
That does not mean that getting a flu shot provides certain protection for anyone, old or young. Unlike some disease germs, flu viruses are constantly changing as their genes mutate and shift. Sometimes viruses exchange genes.
Birds carry viruses, some of which can spread to humans, so diseases like influenza can spread across the world during migration seasons.
Vaccine effectiveness of 40% may be all that can be hoped for in a difficult year, authorities say. Sometimes effectiveness reaches 60% or more.
Effectiveness depends on the ability of medical intelligence teams to foresee the three or four specific virus strains that will be most responsible for making people sick months before the flu season starts.
Modified and new strains sometimes appear in the months after the predictions.
Last year, the CDC estimated that the vaccine was 36% effective, meaning that those who were vaccinated were 36% less likely to get the flu than people who were not.
To Kaiser’s Jonathan Blum, who is chief of the infections disease group at Kaiser’s Santa Clara medical center, a near-40% effectiveness rate was not bad. “We would like it to be better, but 40% is pretty good when you’re talking about a serious illness. It’s a good start.”
He notes that automobile seatbelts do not give perfect safety, either. Someone who normally wears a seatbelt would not be likely to take it off because it is only partly protective. “Of course he would wear it,” Blum said.
This year’s flu season may or may not be as severe as last year’s, Blum said. “The one prediction you can make about flu is that flu is unpredictable.”
The flu season now ending in the southern hemisphere has been relatively mild. “There are no signs” so far that the northern hemisphere will be different from the southern, he said, “but you have to understand that there are no signs until there are signs,” he said.
To ValleyCare’s Scott, it’s important to remember that getting a flu shot “doesn’t just protect you. It protects others around you.”
He cited the “3 C’s” for slowing the flu’s spread:
CONTAIN the disease by staying home if you have flu symptoms (fever, aching joints, dry cough),
COVER coughs and sneezes with your elbow and sleeve, not your hand, and
CLEAN hands by washing with soap and using alcohol gel.
He considers it a “social imperative and responsibility” to avoid being part of the chain of contagion that spreads a potentially lethal disease.
“Those 180 children died last year – that’s 180 families that lost kids to a preventable illness.
“Those kids who died – they got the flu from somebody.”