Last updated: Apr 22, 2016

We thought it was the flu. On a bleak afternoon this past winter, my 16-year-old daughter came home early from school, complaining of a fever and sore throat. Less than 48 hours later, I was sitting next to her in an ambulance, careening toward the nearest emergency room.

It wasn't the flu. An underlying urinary tract infection and a nascent case of strep throat had combined forces to create a perfect storm in my daughter’s body, and she had gone into septic shock—the most severe stage of sepsis, a potentially fatal condition and a leading cause of all in-hospital deaths.

What is sepsis?

Sepsis is an extreme bodily response to infection, in which inflammation throughout the body can lead to organ damage and even organ failure. It’s often characterized by fever, a high heart rate, low blood pressure, confusion, and dizziness.

Sepsis doesn't have a particular season of the year, and it can hit almost anyone, regardless of age or prior health. In March, Oscar-winning actress Patty Duke died of sepsis from a ruptured intestine at the age of 69. In 2009, 20 year-old Brazilian model Mariana Bridi da Costa died within days after a UTI turned into an aggressive case of sepsis.

"People with sepsis can slip from what seems like routine infection into a systemic situation very quickly,” warns Anthony Fiore, MD, chief of Epidemiologic Research and Innovations in the Division of Healthcare Quality Promotion at the Centers for Disease Control and Prevention (CDC).

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If it’s such a big deal, why haven’t I heard of it?

Because there currently isn't a single standard methodology for assessing sepsis, hard statistics on its prevalence and mortality rates can be hard to pin down. But according to the CDC, over one million cases of sepsis occur each year, and it’s the ninth leading cause of “disease-related deaths." The National Institutes of Health reports that sepsis kills more people in the U.S. than prostate cancer, breast cancer, and AIDS combined.

Yet while less common conditions like Ebola and Zika garner big headlines, you may not have ever even heard of sepsis before. Donald Landry, MD, chair of medicine at New York-Presbyterian/Columbia University Medical Center, has a theory about that. "It's a syndrome, not a disease," he says. "It gets buried in other conditions. It doesn't register with the public as something identifiable."

How can I recognize the symptoms?

Fortunately, once you know the warning signs, sepsis can be recognized and effectively treated—and often with no further long term consequences.

"If you get an infection, you're likely to have a fever and likely going to feel somewhat lousy,” explains Craig M. Coopersmith, MD, a past president of the Society of Critical Care Medicine. “But if you feel there's anything above and beyond that—if you feel your heart racing, if you're breathing fast, if your family recognizes that you're confused, if it feels like you're making less urine than usual—anything that feels abnormal to yourself or your loved ones might be a warning sign that not only might you have an infection, you might have an organ dysfunction. And if you do, that is a true medical emergency, because your health and potentially the life of yourself or of your loved one might be at stake."

If you suspect sepsis in yourself or a loved one (besides those listed above, other signs include pale or discolored skin, rash, and, as the CDC helpfully puts it, “I feel like I might die”) the CDC recommends heading to the emergency room and saying directly, “I am concerned about sepsis.”

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My daughter's story has a happy ending. After a terrifying 36 hours in the ER and a potent mix of antibiotics, fluids, and dopamine, her condition stabilized. She spent a few days in the intensive care unit and another week recovering, then returned to school with no other ill effects than falling behind on her math homework.

That's the easily achieved outcome I now want for so many more families like mine. Simple awareness can make all the difference. As Dr. Coopersmith says, "If sepsis is recognized in every patient and treated rapidly and appropriately, we can save multiple thousands of lives a year."