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Ways The Flu Can Turn Deadly

By Jeff Hayward

Medically Reviewed by Patty Weasler, RN

We know the flu can be fatal – after all, we’re hearing almost weekly updates on the news about the casualties from the current flu season, no thanks mostly to the H3N2 strain, which reared its ugly head this year.

While most people who get the flu won’t need to seek medical attention, some cases will go sideways and can lead to dangerous symptoms. Here are 12 ways flu can get out of hand and possibly lead to death…

Second Wave

Those who recover from influenza aren’t out of the woods yet, as there are secondary infections that can present even worse symptoms. ABC News says the most common secondary infections are bacterial pneumonia, bacterial sinusitis or bacterial otitis.

While flu viruses aren’t responsive to drug therapies (aside from antivirals that are effective up to 48-hours after symptoms appear), the “good news” is that these secondary bacterial infections usually respond to antimicrobial therapy, which can kill of bacteria or fungi, it adds.

Pneumonia a Possible Killer

The flu can lead to bacterial or viral pneumonia, neither of which is good. All that extra coughing and mucus production from the flu can set the stage for an infection like pneumonia to walk into the scene, says

The infection related to pneumonia could “spread to their bloodstream and cause an overwhelming, multi-system infection,” even in some people who were otherwise healthy, adds the source. While this scenario is not common, the complications can end in death.

Sepsis an Unwelcome Outcome

There have been reports of people dying soon after being diagnosed with flu, and the culprit in some cases is actually septic shock, explains Sepsis, as it’s known, can be triggered by an infection such as influenza and reduces blood flow to vital organs, it adds.

The source explains about 1.5-million Americans experience sepsis every year, and about 250,000-people die from it as a result. Sepsis typically is triggered by an overwhelming blood infection that causes a dysfunctional immune response. Patients experience very low blood pressures and poor oxygenation that can lead to death if not treated quickly.

Heart Problems Linked to Sepsis

Sepsis can cause further (possibly fatal) complications such as a heart attack, and the culprit behind heart damage from sepsis was discussed in a 2015 article in ScienceDaily.

A research team found that “nuclear proteins” called histones cause damage to heart muscle cells following cell damage caused by sepsis. It notes that histones “are robust biomarkers that can predict which patients are more likely to develop heart complications.”

Other Complications

If someone with the flu has a pre-existing condition, such as asthma, it can be especially dangerous, says Healthline. The source says the flu can cause “increased sensitivity to allergens and other asthma triggers” from inflammation of the airways.

Meanwhile, pregnant women who contract influenza (with a fever) may be at risk for giving birth prematurely, which can increase the risk of the child having defects of the brain and spine, it adds. Meanwhile, the mother-to-be herself may be at higher risk of dying from flu complications, it adds.

Age Plays a Role

Unfortunately, the flu is especially mean to children who are otherwise helpless. says that as of Feb. 28, 97-children in the U.S. have passed away from flu complications this season, which is tragic any way you look at it.

The problem (other than being unvaccinated) is that the immune systems of some relatively healthy younger children (under 5-years) haven’t had a chance to fully develop yet, and are “only moderately effective at fighting infection,” notes the source. Babies under 6-months can’t get a flu shot, but pregnant women should and can pass along immunity to their unborn child by doing so, it adds. Meanwhile, the elderly are also at higher risk of dying from flu complications, as immune responses drop with age.

Ineffective Flu Shots

Each flu season, scientists try to predict which strains of influenza will be most prominent so they can develop the most effective vaccines. Unfortunately, this year’s shot has been said to have effectiveness as low as 15-percent, according to Cosmos magazine.

The typical rate of protection is around 50-percent, adds the source. However, this doesn’t mean you shouldn’t get a flu shot (even now, because flu season can extend well into spring), which we’ll get to next.

Not Getting a Vaccine

A 2017 article from CBS News said that many deaths (especially among children) could be prevented with a flu shot, but a study looking at 4-flu seasons found that only 25-percent of so that died had been vaccinated.

“If all children got their yearly flu shot, 65-percent of those deaths could be prevented,” reads the article. Don’t let the fact that your children appear healthy and seemingly invincible to common illnesses; even some otherwise healthy children are falling victim to flu complications.

A Particularly Nasty Flu Season

It’s true that this season’s flu has been especially unkind, mostly due to the H3N2 viral strain. “H3N2 is particularly virulent, meaning it causes a more severe flu and is more easily spread,” it notes.

The H3N2 variation of the flu virus is also especially tough on the young and elderly, “meaning that these vulnerable populations are even more at risk than usual,” it adds. That means getting a flu shot, and then being more vigilant about certain signs and symptoms.

Not Recognizing Signs in Kids

Younger children may not be able to communicate verbally with you, but they are one of the highest risk groups when it comes to dying from flu complications.

In fact, CaringForKids says that influenza “is more severe in children under 2 years of age,” which is a time when a child may only be using simple phrases. In this case, you should keep an eye on possible complications of the flu, which we’ll cover next.

Ignoring Emergency Signs

Knowing the signs of when flu can turn deadly can help save the life of a child or adult. LiveScience has a list of symptoms that require emergency medical intervention.

For example, in adults, you should go to the ER if you have difficulty breathing, chest or abdominal pain, sudden dizziness, severe vomiting, and signs of a secondary illness (after the flu seems to have cleared up). In children, don’t ignore bluish skin tones, rapid/labored breathing, extreme irritability, and a fever with a rash.

Not Knowing Prevention Tips

The best way to avoid developing flu complications is by knowing how to prevent it in the first place, but not everyone practices these tips from the Centers for Disease Control and Prevention.

These healthy habits include avoiding close contact with an infected person, staying home when you’re sick, covering your mouth and nose with a tissue when coughing or sneezing (or using your upper sleeve), washing your hands often with soap and water, avoiding touching your eyes, nose and mouth, and disinfecting solid surfaces home – especially if there’s a sick person in the house.


Patty is a freelance health writer and nurse (BSN, CCRN). She has worked as a critical care nurse for over 10 years and loves educating people about their health. When she's not working, Patty enjoys any outdoor activity that she can do with her husband and three kids.

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