1Infection
The trigger
The trigger
- Bacteria, viruses, fungi, or parasites cause an infection.
- Common sources include lungs, urinary tract, abdomen, and skin.
- Most infections do not lead to sepsis.
Sepsis
A global health emergency
When infection turns into a life-threatening systemic response.
Sepsis is life-threatening organ dysfunction caused by a dysregulated response to infection. It can lead to organ failure, long-term complications, and death. Understanding sepsis helps us recognize the signs early and support people at risk.
Learn more →Infection
(triggers immune response)Dysregulated
inflammation
(harms the body)
(triggers immune response)Dysregulated
inflammation
(harms the body)
Global Burden
Estimated worldwide cases and sepsis-related deaths.
~49 millioncases in 2017
~11 milliondeaths in 2017
U.S. Burden
CDC estimates for adults each year.
~1.7 millioncases≥350,000deaths or hospice discharges
- Most cases begin before hospital admission.
- Underlying conditions are common.
- Sepsis requires immediate evaluation.
Who Is Most Affected?
Older adults have an increased risk.
Risk increases with age
Adults aged 65 and older are among the groups at increased risk of sepsis. Risk also depends on chronic conditions, immune suppression, recent severe illness and other factors.
These factors describe risk groups, not an individual prediction.
CDC: About sepsis →65+
Older adults are at increased risk of sepsis.
How Sepsis Develops
A dynamic immune response that can change over time.
1
2Hyperinflammation
Can begin early; timing varies
Can begin early; timing varies
- Dysregulated inflammatory pathways damage blood vessels and tissues.
- Microcirculatory changes can impair organ function.
- Fever or low temperature, rapid breathing, and confusion may occur.
3Immunosuppression
Can coexist early or persist
Can coexist early or persist
- Inflammation and immunosuppression can coexist.
- Immune-cell dysfunction can weaken infection control.
- Some survivors face recurrent infection and long-term complications.
The immune response in sepsis
Hyperinflammation
Excessive inflammatory activity can contribute to tissue damage.
Immunosuppression
Reduced immune defenses can increase susceptibility to infection.
These responses can overlap; their timing and severity vary.
Conceptual illustration, not fixed phases. Inflammation and immunosuppression can coexist from early sepsis.
Common Sources of Infection
Sepsis can originate from many types of infection.
Recognize the signs
Confusion, shortness of breath, extreme pain, fever or shivering, and a fast heart rate can signal sepsis. Seek urgent medical care if sepsis is suspected.
Prevention and What You Can Do
Lower infection risk. Recognize the signs early.
- Keep up to date with recommended vaccines.
- Practice hand hygiene and wound care.
- Get prompt care for serious infections.
- Manage chronic conditions with your health-care team.
- Watch for a worsening infection, confusion, or breathing difficulty.
- Ask: “Could this infection be leading to sepsis?”
Treatment is urgent
Sepsis needs rapid hospital assessment and treatment, which may include antimicrobials, fluids, organ support, and control of the infection source.
Key Facts
~49 million
estimated global cases in 2017
~11 million
sepsis-related deaths in 2017
~1.7 million
U.S. adult cases each year
≥350,000
U.S. adult deaths or hospice discharges
Major cause
of death and hospitalization
High risk
older adults and people with chronic conditions
Selected sources and references
Artwork illustrates the main mechanisms schematically; molecular sizes, colors and distances are not literal.