DiagnoseWise
Home Articles Resources About Contact

Disease

Sepsis

Learn about sepsis, including its symptoms, diagnosis, laboratory tests, treatment and prevention.

Last Reviewed 22 Jul 2026
Reading Time 8 min read

Overview

Sepsis is the body’s extreme and life-threatening response to an infection. Rather than being caused by one specific germ, sepsis happens when an infection already present in the body triggers a chain reaction that damages the body’s own tissues and organs.

💡

Key Fact

Sepsis is a medical emergency. It can be triggered by almost any infection, and without fast treatment it can quickly lead to tissue damage, organ failure, and death.

Warning

Sepsis can worsen within hours. If sepsis is suspected, seek emergency medical care immediately rather than waiting to see if symptoms improve.

AT A GLANCE

Disease Summary

Category Infectious Disease
Cause Triggered by an infection - bacterial, viral, fungal, or parasitic
Transmission Not directly transmissible between people; arises from an existing infection
Body System Whole body (multiple organ systems)
Preventable Yes
Curable Yes

Symptoms

Common Symptoms

There is no single sign of sepsis. It usually presents as a combination of the following symptoms alongside signs of an existing infection.

Fever or Low Body Temperature

Either a high fever or an unusually low body temperature can occur.

Fast Heart Rate

The heart often beats faster than normal as the body tries to compensate.

Fast Breathing

Rapid, shallow breathing is a common early sign.

Confusion or Disorientation

Sepsis can affect brain function, causing confusion or difficulty thinking clearly.

Danger Signs

Seek urgent medical attention immediately if any of the following develop.

Severely Low Blood Pressure

May indicate progression to septic shock, a severe and life-threatening stage of sepsis.

Difficulty Waking or Extreme Sleepiness

A sign that the body’s organs may be failing and requires immediate care.

Mottled or Discoloured Skin

Can indicate poor blood flow to the skin and underlying tissues.

Little or No Urination

May indicate the kidneys are being affected and requires urgent evaluation.

Diagnosis

Clinical Assessment

Diagnosis begins with a clinical evaluation of vital signs, mental state, and evidence of an underlying infection. Sepsis is a clinical diagnosis and is not ruled in or out by a single test alone.

Blood Cultures

Blood cultures are collected as soon as possible, ideally before antibiotics are given, to identify the underlying infection.

Lactate Testing

Blood lactate levels help assess how severely the body’s tissues are being affected and guide urgency of treatment.
Important
Because sepsis can resemble many other conditions, healthcare providers rely on a combination of clinical signs and laboratory tests together, not any one test alone.

Laboratory Tests

Blood Cultures

Identifies the specific bacteria or organism causing the underlying infection, guiding antibiotic choice.

Sample Venous blood
Time 24–72 hours for full results

Lactate Level

An elevated lactate level indicates the body’s tissues are not getting enough oxygen, a sign of worsening sepsis.

Sample Venous or arterial blood
Time Under 1 hour

Complete Blood Count (CBC)

Helps identify signs of infection and assess how the body is responding.

Sample Venous blood
Time 30–60 minutes

Additional Cultures

Samples from the suspected source of infection, such as urine or a wound, help confirm where the infection started.

Sample Urine, wound, or respiratory samples
Time 24–72 hours

Laboratory Note

No single laboratory test can confirm or rule out sepsis. Results are interpreted together with the person’s clinical condition.

Treatment

Antibiotics

Broad-spectrum antibiotics are given as early as possible, then adjusted once the specific cause of infection is identified.

Route Intravenous (IV)
Duration Started within 1 hour of recognition

IV Fluids

Fluids are given to help maintain blood pressure and blood flow to vital organs.

Route Intravenous (IV)
Duration Within the first few hours

Treatment Note

Sepsis treatment begins immediately, often before all test results are back. Early antibiotics and fluids significantly improve outcomes.

Prevention

Prevent infections where possible

Practising good hygiene, keeping wounds clean, and staying up to date on recommended vaccines all reduce the risk of infections that can lead to sepsis.

Manage chronic health conditions

Conditions such as diabetes increase the risk of infections progressing to sepsis, so ongoing management matters.

Know the signs and act fast

Recognising the early signs of sepsis and seeking care immediately is one of the most effective ways to prevent it from becoming life-threatening.

Prevention Note

Anyone with a known infection who develops confusion, a fast heart rate, or fast breathing should seek medical attention promptly.

Risk Factors

High Risk

These individuals are more likely to develop severe sepsis.

  • Infants and young children
  • Adults over 65
  • People with weakened immune systems

Increased Risk

These groups have a higher chance of developing sepsis.

  • People with chronic conditions such as diabetes or kidney disease
  • People recently hospitalised or who have had recent surgery
  • People with wounds or invasive medical devices

Exposure Factors

Situations that increase the risk of developing an infection that could lead to sepsis.

  • Untreated or delayed treatment of infections
  • Limited access to healthcare
  • Poor wound care

Risk Note

Most people who develop sepsis have at least one underlying medical condition or recent hospitalisation, but sepsis can affect anyone with an infection.

Complications

Septic Shock

A severe drop in blood pressure that significantly increases the risk of death and requires immediate intensive care.

Organ Failure

Sepsis can damage the kidneys, lungs, liver, or other organs if not treated promptly.

Long-Term Effects

Survivors may experience ongoing physical, cognitive, or mental health effects after recovering from severe sepsis.

Complication Note

Sepsis is a leading cause of death from infection worldwide. Early recognition and treatment greatly reduce the risk of these complications.

When to Seek Medical Care

Signs of Infection Plus Confusion

Confusion alongside a known or suspected infection requires immediate emergency care.

Very Fast Heart Rate or Breathing

These may indicate the body is struggling to compensate for a serious infection.

Low Blood Pressure or Fainting

May indicate septic shock and requires emergency medical attention.

Little or No Urination

Can indicate the kidneys are being affected and should be assessed urgently.

Emergency Advice

Sepsis is a medical emergency. Do not wait to see if symptoms improve on their own, seek care immediately.

Prognosis

Improved with Early Treatment

Outcomes are significantly better when sepsis is recognised and treated within the first hour.

Serious if Treatment is Delayed

Delayed treatment increases the risk of septic shock, organ failure, and death.

Recovery and Follow-Up

Some survivors experience lasting effects and may need ongoing follow-up care after leaving hospital.

Prognosis Note

Sepsis affects an estimated 49 million people worldwide each year. Early recognition and treatment remain the most important factors in survival.

Differential Diagnosis

Severe Malaria

Severe malaria can present with fever, confusion, and organ dysfunction similar to sepsis, particularly in endemic regions.

Typhoid Fever

Typhoid fever can cause prolonged fever and, in severe cases, complications that overlap with sepsis.

Dehydration

Severe dehydration can cause a fast heart rate and low blood pressure, requiring careful clinical distinction from sepsis.

Heart or Lung Conditions

Some cardiac and respiratory conditions can mimic early sepsis symptoms such as fast breathing and low blood pressure.

Clinical Note

Because sepsis can be triggered by many different infections and can resemble other serious conditions, prompt clinical assessment is essential rather than relying on symptoms alone.

References

World Health Organization (WHO)

World Health Organization guidance on sepsis epidemiology, risk factors, and prevention.

Centers for Disease Control and Prevention (CDC)

Clinical guidance and public education resources on recognising and preventing sepsis.

Surviving Sepsis Campaign

International clinical guidelines for the management of sepsis and septic shock.

Mayo Clinic

Patient-focused overview of sepsis symptoms, causes, and complications.

Frequently Asked Questions

Is sepsis contagious?
No. Sepsis itself does not spread from person to person. It develops from an infection that is already present in someone’s own body.
Can sepsis be cured?
Yes, especially when recognised and treated early. Outcomes are much better when antibiotics and fluids are started within the first hour of recognition.
Who is most at risk of sepsis?
Infants, older adults, people with weakened immune systems, and people with chronic health conditions or recent hospitalisation are at higher risk, though anyone with an infection can develop sepsis.
Can sepsis be prevented?
Yes, to an extent. Preventing and promptly treating infections, practising good wound care, and staying current on vaccines all reduce the risk.