Sepsis occurs when the body’s response to an infection spirals out of control, damaging its own tissues. Common causes include bacterial, viral, and fungal infections. Risk factors of sepsis include advanced age, chronic illness, recent surgery, and a weakened immune system. Early recognition saves lives.
Sepsis is a medical emergency. Every year, it affects more than 1.7 million adults in the United States, according to the Centers for Disease Control and Prevention (CDC). Yet many people do not recognize it until it has already become life-threatening.
Understanding the causes of sepsis — and knowing who is most at risk — can make the difference between catching it early and facing its most devastating consequences. The information below will help you protect yourself and the people you love.
What Causes Sepsis?
Sepsis does not begin in the bloodstream. It begins with an infection — and then the body’s immune response goes too far.
What role do bacterial infections play in causing sepsis?
Bacterial infections are the most common cause of sepsis. Pneumonia, urinary tract infections, skin infections, and abdominal infections are among the most frequent triggers. Bacteria like Staphylococcus, Streptococcus, and E. coli are regularly identified in sepsis cases.
Can viral and fungal infections also cause sepsis?
Yes. Viral illnesses — including influenza and COVID-19 — can trigger sepsis, particularly in vulnerable individuals. Fungal infections, while less common, are a growing concern for people with weakened immune systems, such as those undergoing chemotherapy or long-term steroid treatment.
Are there non-infectious triggers of sepsis?
In some cases, the immune system overreacts to a non-infectious injury, such as a severe burn, trauma, or pancreatitis. These situations can produce a sepsis-like response even without a detectable infection present.
Warning Signs and Symptoms to Watch For
Sepsis can look like many other conditions, which is part of what makes it so dangerous. If you or someone you care for has a known or suspected infection and begins showing any of the following symptoms, seek emergency care immediately:
- High fever or unusually low body temperature
- Rapid heart rate or breathing
- Confusion, disorientation, or extreme sleepiness
- Extreme pain or a feeling of impending doom
- Clammy, pale, or discolored skin
- Low urine output
- Dizziness or fainting
These symptoms can progress quickly. Do not wait to see if they improve on their own.
Risk Factors of Sepsis: Who Is Most Vulnerable?
Anyone can develop sepsis, but certain groups face a significantly higher risk. Knowing where your loved one falls on that spectrum helps you act faster when early signs appear.
Age:
Adults over 65 and children under one year old are at the greatest risk, according to the CDC. The immune system is less equipped to mount a controlled response at these life stages, making infections harder to contain.
Chronic Conditions:
Diabetes, cancer, chronic kidney disease, and lung disease all weaken the body’s ability to fight infection. Each condition disrupts immune function in different ways, but the result is the same: a higher chance that an ordinary infection becomes something far more serious.
Recent illness, surgery, or hospitalization:
Yes — significantly. Medical procedures create entry points for bacteria. Patients with catheters, IV lines, or recent surgical wounds are especially vulnerable during recovery.
Weakened immune system:
People taking immunosuppressant medications, those living with HIV, and transplant recipients have reduced immune defenses. For these individuals, even a minor infection can escalate rapidly.
Pregnant and postpartum women:
Pregnancy changes immune function in ways that can make infections harder to fight. Sepsis is one of the leading causes of maternal mortality worldwide, according to the NIGMS. Postpartum women remain at elevated risk for several weeks after delivery.
Sepsis survivors:
Surviving sepsis does not protect against it. Many survivors experience lasting immune dysfunction, making them more susceptible to future infections and repeat episodes of sepsis.
When Should You See an Infectious Disease Specialist?
If you or a loved one has recently recovered from a serious infection, experienced sepsis, or lives with a chronic condition that raises your risk, a consultation with an infectious disease specialist is a meaningful next step. These physicians are trained to identify infection sources, review your medical history for patterns, and create a plan to reduce your future risk.
For families in the New York area, infectious disease doctors in Brooklyn can provide expert evaluation close to home. Connecting with infectious disease doctors in Brooklyn early — rather than waiting for a crisis — gives you and your family a clearer path forward.
Take the Next Step With Our Department
Sepsis is serious, but it is not inevitable. Recognizing the causes of sepsis, spotting symptoms early, and understanding your personal risk factors puts you in a position to act — not react.
Our team is here to support you every step of the way. Whether you are managing a chronic condition, recovering from a recent hospitalization, or caring for someone who survived sepsis, our Infectious Disease team is ready to help. Reach out today by calling + 1-718-367-2555 or visiting us at 1797 Pitkin Avenue, Brooklyn, NY 11212 to schedule a consultation and take the first step toward better protection for you and your family.
