The Flu and Its Link to Sepsis

Flu season is always a stressful time, especially for those caring for young children and the elderly. Some years carry a higher threat of complications than others. The flu vaccine does not always work against every strain that dominates the season. Some strains are also more severe than others, causing widespread panic. The flu can easily lead to pneumonia, an infection of the lungs. As the body tries to fight this, it can take a wrong turn. Sepsis occurs when the body stops fighting the infection and starts fighting itself.


Sepsis occurs in response to infections of the skin, kidneys, gut, or lungs.  These infections illicit a strong immune response from the body. Your immune system normally goes into attack mode when an infection is present. When doctors are looking for infection, they often do bloodwork to determine the amount of white blood cells in the blood. An elevated amount indicates an infection. Sepsis occurs when the body begins attacking itself instead of the intruding bacteria. This response causes dangerous levels of toxicity and inflammation.

Bacterial infections usually prevail when sepsis occurs. This is what confuses people most about sepsis and the flu. Sepsis occurs due to secondary infections, not usually the flu itself. Sepsis can vary in severity and is described in three ways. There is sepsis, severe sepsis, and septic shock. There is about a 50% survival rate for those that go into shock. Severe sepsis and septic shock are accompanied by organ damage, difficulty breathing, and extremely low blood pressure. Deaths are often related to heart failure, as the body becomes overwhelmed. Those that do survive, may have sleep problems, cognitive issues, and chronic fatigue.

Flu and Pneumonia 

The flu is a viral infection that must run its course once it enters the body. It is a respiratory illness that often causes congestion and coughing. Fever, chills, and vomiting are also symptoms to look out for. It is different from the common cold, as it hits suddenly and causes extreme lethargy. Some strains are more severe and result in more incidents of hospitalization. When the news starts stating that people are dying of the flu, they usually do not clarify that these deaths are in relation to complications associated with the flu. This often causes panic instead of introducing the necessary education about the illnesses.

The severity of the flu leaves your body at risk for secondary infections. Respiratory illness can easily travel from the upper airways down the bronchial tubes into the lungs. There is viral and bacterial pneumonia. The bacterial form is the one most commonly related to sepsis and death. Streptococcus bacteria is the main cause of bacterial pneumonia. Streptococcus bacteria normally live in the environment and in your throat. A healthy individual, however, is able to keep it under control. Once the immune system drops, however, it is more likely that the body is unable to control the bacteria. The bacteria then spreads down into the lungs.

Pneumonia is often noticed after an individual starts to recover from the flu and then suddenly gets worse. An onset of pneumonia early on during the flu illness can easily be overlooked due to flu symptoms. Patients should insist that their blood count and lungs be checked during a flu illness, especially if they have extreme discomfort. Early detection of complications is key to preventing or surviving sepsis.

The Link

The trail from the flu to sepsis may seem like a lengthy one, however, it can occur within a few days of exposure to the flu. Once your immune system is down, you fall prey to many more complications. The flu takes hold first, engaging your body in an all-out war against viral invaders. Once your body is weakened, it cannot keep normal bacteria in check. This then moves down into the lungs, causing pneumonia. Researchers in the medical field are unsure what causes the chaos of sepsis in some patients, but not others. The bacteria from the pneumonia is what seems to trigger the sepsis. By the time a patient begins symptoms of severe sepsis, you have very little time before they go in to septic shock, impeding the chance of survival and full recovery.  At this point, blood flow to the kidneys, brain, and heart may be limited. Early detection is the best way to gain a chance of surviving sepsis. Flu patients should be aware of the warning signs of sepsis.

  • Fever or low body temperature
  • Swelling
  • Fast respiratory rate
  • Heart rate exceeding 90 beats per minute
  • Alterations in cognitive reasoning
  • Dizziness
  • Lack of urinary output
  • Low blood pressure
  • High white blood cell count

Individuals that are treating the flu at home can take notice if their fever and chills worsen, or they have an overwhelming feeling of discomfort bad enough to warrant the phrase “I feel like I am going to die.” Once sepsis begins, a certain shift in the severity of the flu symptoms occurs. It may be subtle at first, but quickly progresses.

Sepsis often occurs when people have the flu due to a weakened immune system. Once the immune system wages war on itself, quick action is required. Otherwise damage to the heart, brain, and other organs can result. Sepsis seems to be a perfect storm of reactions that happen in a predictable order once the flu has set in. Pneumonia and sepsis do not plague everyone who gets the flu. Many people recover from the flu with no complications. Awareness of the origins of sepsis and the symptoms, however, can save lives.

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There are very few people on this planet who enjoy their work more than Aner Banner. His friends often readily admit that Aner eats, sleeps, and breaths science 24 hours a day. He is always challenging old methods, proposing new ideas, and seeking to solve difficult problems. Aner spends most of the day imparting his wisdom to the young minds of a small elementary school. Thankfully he has also mastered the art of making science come alive for the future leaders of our nation. He is loved and well respected by students, parents, and faculty alike. His motto forever remains “never stop learning.

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