For most of the millions of people who get the flu each year in the U.S., the virus brings a few days of fever, body aches and weakness before it goes away.
But for some, the influenza virus can lead to severe illness, hospitalization — even death.
Allison Miller knows these risks all too well. This year marks a decade since serious complications from the flu led to a life-changing loss for the Virginia-based communications director.
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At age 33, Miller was a healthy young woman when she came down with a sore throat and headache.
When her symptoms got worse, she went into urgent care for a chest X-ray, but it showed nothing alarming.
"It looked like it was just some sort of run-of-the-mill stuff — they gave me some prescription cough syrup and said to let them know if it got worse," she said in an interview with Fox News Digital.
Back at home that night, Miller started feeling worse — and began having intense back pain.
"Thinking it was the flu or something I could get over, I kept waiting to turn the corner — like, this is the worst of it. It'll get better. And clearly that wasn't the case," she said.
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The next morning, when the back pain was causing her to have periodic blackouts, Miller managed to call a friend, who came over and called an ambulance.
That’s where Miller's memory stops.
"I remember being loaded into the ambulance — and then I really don't remember a whole lot after that for about three weeks to a month thereafter," she said. "It just escalated very quickly."
As Miller would later learn, her influenza had caused bilateral bacterial pneumonia — which affects both lungs and is more severe than viral pneumonia.
This led to sepsis, which quickly turned to septic shock.
"All of my organs were shutting down," Miller said. "Within a short amount of time, I was in the ICU and they were doing everything they could. But ultimately, my last best chance was to be put on life support."
After five days, Miller experienced a rare complication.
"A known complication of that form of life support is amputation," she told Fox News Digital. "Some patients lose blood circulation, and that's what happened to me."
Ultimately, doctors had to amputate Miller’s left leg above the knee — all while she was still in a medically induced coma.
"By the time I came out of it, it had been three weeks. I awoke in a very hazy position — and I didn’t have a left leg," she recalled.
She spent another two months in the hospital and then had to do weeks of inpatient rehabilitation.
Today, in what Miller refers to as her "new normal," she wears a prosthesis and — with the help of "very qualified people" — has learned to walk again and to "navigate the world and all of its terrain."
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Miller has been able to get back to the things that she loves to do, such as traveling the world, without feeling limited by her disability.
"It's just different, and I have learned to adapt and adjust," she said.
In addition to the amputation, Miller still suffers from permanent lung damage and below-average heart function.
"There was some permanent organ damage because of the strain of the virus, as it was such a severe case of pneumonia," she said. "I have a terminal lung condition that needs regular treatment."
She added, "It's manageable, but it's something I will forever deal with."
The experience has given Miller a "renewed sense of how quickly things could change" — and has taught her to be as proactive as possible about her health to prevent a terrible outcome.
Overall, Miller said she thinks most people don’t understand how severe the flu can be — so they don’t recognize the signs that they need immediate medical attention.
"In my case, it was very quick — it was within 24 to 48 hours that it went from just coming on, to me being in the hot seat."
Now, Miller is looking to spread awareness of the importance of getting the flu vaccine, which she did not get that year.
"I had missed the memo that flu vaccines were for everyone, and being 33 at the time and otherwise healthy, it didn't even register as something I should consider doing," she said.
"If there's anything you can do proactively to minimize the risk of something that severe happening to you, you absolutely should do it, I think."
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Miller acknowledges that the vaccine doesn’t guarantee that someone won't get the flu, but noted that "it's more of a continuum, rather than either you're sick or you're not."
She said, "You still might get it, but you may not end up in the ICU like I did … Considering the benefits that you could get and what the extreme, worst outcome could be, it is an easy thing to do that is proven to make a tremendous difference for people," she added.
In addition to getting yearly vaccines, Miller takes steps to minimize her exposure and makes healthy lifestyle choices, such as eating nutritious foods and exercising.
Dr. Gregg Sylvester, chief health officer at CSL Seqirus, a New Jersey biopharmaceutical company, noted that while Miller’s experience is not typical of most women in her age range, "it probably occurs more often than we know."
The flu triggers inflammation of the respiratory tract, Sylvester said, which causes it to become irritated and can allow secondary or bacteria to enter.
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"A viral illness like influenza can set you up for something more serious further on," he warned. "That's why it's so important to get a vaccine."
The more severe complications of flu often are markedly reduced for those who get an influenza vaccine, according to the doctor.
"You still may end up getting infected, but your symptoms will be milder," he said. "And hopefully, your respiratory tract will be in a little bit better shape."
Mid-October is the "perfect time" to get a flu vaccine, Sylvester said, as he noted that the U.S. is starting to see an upswing in cases.
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"It's never too late, but it is important to be vaccinated before the season really gets started," he said.
Overall, Miller urged, "don't dismiss the flu as just the flu. It's so much more than that. And it can be life-altering."
She continued, "If you're sick and the symptoms are severe, don't waste time wondering if you should seek medical attention. Listen to your body — it’s better to go in proactively, rather than regret it later."
Sylvester agreed, stressing the need for people to be their own patient advocates.
"It's important to seek care early, especially if symptoms start to change dramatically," he said.
During the 2021-2022 influenza season, the Centers for Disease Control and Prevention (CDC) estimates that there were nine million illnesses, four million medical visits, 10,000 hospitalizations and 5,000 deaths related to the flu.
The CDC recommends that everyone 6 months and older get a flu vaccine every season, with rare exceptions.
