The useful points to carry forward
- Confusion, disorientation or an unusual change in alertness.
- Shortness of breath or visibly difficult breathing.
- Fever, shivering or feeling unusually cold.
- A high heart rate, weak pulse, or clammy and sweaty skin.
Sepsis begins with an infection
Sepsis is the body's extreme response to an infection and is a life-threatening medical emergency. The infection may begin in places such as the lungs, urinary tract, skin or digestive system. Bacterial infections cause many cases, but viral and fungal infections can also lead to sepsis.
There is no reliable home test that can confirm or rule out sepsis. The important pattern is an infection—or possible infection—together with a person becoming seriously or rapidly unwell. Fast professional evaluation matters because sepsis can progress to tissue damage and organ failure.
Look for a concerning combination
A person with sepsis may have one or several warning signs, and not everyone will develop a fever. Pay attention to a marked change from the person's usual state, especially while an infection is worsening or not improving.
These signs also occur in conditions other than sepsis, so the list is not a diagnostic checklist. A healthcare team must assess the whole situation, including vital signs, examination findings and tests.
- Confusion, disorientation or an unusual change in alertness.
- Shortness of breath or visibly difficult breathing.
- Fever, shivering or feeling unusually cold.
- A high heart rate, weak pulse, or clammy and sweaty skin.
- Extreme pain, severe discomfort or a strong sense that something is seriously wrong.
Who needs particular awareness
Anyone can develop sepsis, but risk is higher in babies younger than one year, adults aged 65 or older, people with chronic illnesses or weakened immune systems, pregnant or recently postpartum people, and those with recent severe illness, surgery or hospital care. Previous sepsis also increases future risk.
If someone with a possible infection is rapidly worsening, confused, very breathless, difficult to wake or otherwise severely unwell, call local emergency services and say that you are concerned about sepsis. For a less dramatic infection that is not improving, contact a healthcare professional promptly. This guide does not diagnose sepsis or replace emergency assessment.
Guidance can change. This source was last checked for this article on 3 October 2026. See the editorial policy.