Is the Flu Dangerous?

From debilitating illness to flu-related complications, here’s why you should still be concerned about the flu
Elderly woman suffering with flu symptoms

With the COVID-19 pandemic lingering, you may have set aside some concerns about catching the flu, but hold fast: The viral respiratory infection is still one serious illness that peaks between December and February in the Northern Hemisphere.

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According to the Centers for Disease Control and Prevention, the flu has resulted in 140,000 to 170,000 hospitalizations and 12,000 to 52,000 deaths annually in the U.S. between 2010 and 2020. And while you may believe that you can easily survive the flu or that it’s as common as the average cold, many of these beliefs are misconceptions that should be taken seriously, says infectious disease specialist Sherif Mossad, MD.

“Even though the majority of people can get over the flu, clearly there are people who are sick and cannot function,” says Dr. Mossad. “And if you have an underlying disease — like heart disease or lung disease — that could get worse if you get the flu and it could put you in the hospital or keep you out of a job.”

How dangerous is the flu?

You may think you never get the flu, but Dr. Mossad says that’s a common misconception.

“The odds are about 10% to 20% of the population get infected with influenza every year, whether they have been diagnosed or not,” says Dr. Mossad. “If they think they never get the flu, they don’t know because they either didn’t get tested or because they think they never get sick from a viral illness.”

Common colds and the flu are different from one another, but they certainly have similar symptoms. The real trouble occurs when the flu makes other underlying conditions worse, such as heart disease, lung disease, emphysema, heart failure, liver failure and more. And even when you’re at peak health, the flu could lead to heart or muscle inflammation, making it difficult to move or be active, and even lead to secondary bacterial pneumonia.

Pneumonia is a lung infection in which the airways become inflamed and the air sacs of the lungs become filled with fluid. It can be life-threatening. Children under age 2, pregnant women, adults over 65 and people with compromised immune systems are most at risk for developing pneumonia.

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“That could put people in the hospital and require them to be on a breathing machine,” says Dr. Mossad.

Serious symptoms to look out for

The flu spreads quickly through droplets made by people who cough, sneeze or talk while they’re infected. If you have the flu, you can be contagious as early as one day before you start feeling ill and up to five to seven days while you have symptoms.

Symptoms tend to set in suddenly. Some common symptoms of the illness include:

  • Fever.
  • Headache.
  • Cough.
  • Body aches.
  • Chills.
  • Fatigue.

But Dr. Mossad warns that if you’re experiencing shortness of breath, you should go to the hospital immediately.

“If I have progressively worsening shortness of breath, then that’s not right,” says Dr. Mossad. “I have to go to the hospital because if I’m having respiratory failure or heart failure, these can’t be managed at home, and may require oxygen, a breathing machine or heart medications.”

Who is most at-risk?

People 65 and older are most at-risk for complications of the flu due to aging immune systems, but Dr. Mossad says age can be relative depending on your overall health and wellness. Someone who is 65, athletic and has no underlying medical conditions may be as healthy as a 40-year-old who gets influenza. On the other hand, a 35-year-old diagnosed with obesity or diabetes and perhaps smoked for a significant amount of time will be at higher risk of complications of the flu. People with chronic conditions such as heart disease, lung disease or compromised immune systems are also at higher risk.

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Preventing the flu

If you get the flu, the best thing to do is to stay home, get plenty of rest, drink fluids and take over-the-counter medications like acetaminophen and ibuprofen to relieve symptoms. If you recognize symptoms early on, you may be able to receive anti-viral medications from your doctor, which can help the flu not last quite as long. But what can you do to prevent the flu before it even occurs?

The simplest — and fastest — solution is to get the flu vaccine. The CDC recommends everyone over the age of 6 months gets a flu vaccine so long as you don’t have any further underlying conditions or allergies that could compromise your health. And if you’re concerned about whether the flu vaccine will make you sick, Dr. Mossad, who authored an article on vaccine effectiveness, says any sickness experienced post-vaccine is your body’s response to building up its defense against further infection.

“This is a foreign antigen to our body, and the intent of it is for our bodies to develop, not just antibodies, but specific cells to protect us from the infection,” says Dr. Mossad.

Of course, taking care of your overall health to strengthen your immune system is equally important as your body can fortify itself year-round against further infections with each and every flu season.

“In general, staying healthy, eating healthy, exercising and sleeping well are all things that help our immune system fight infections,” says Dr. Mossad.

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