Sepsis is not something you “catch” like a cold; it is a life‑threatening reaction of your body to an infection that you already have.

What sepsis actually is

  • Sepsis happens when an infection (like pneumonia, a urinary tract infection, a skin wound, or abdominal infection) triggers an extreme immune response that starts damaging your own tissues and organs.
  • Any infection can potentially lead to sepsis: bacterial infections are most common, but viruses and fungi can also be triggers.
  • It is a medical emergency, similar in seriousness to a heart attack or stroke, and needs urgent hospital treatment.

A simple way to think about it: you don’t “catch sepsis”; you get an infection , and if that infection overwhelms your body, it can develop into sepsis.

How people end up with sepsis

You increase your risk of developing sepsis when:

  • You have an infection that is not treated quickly or adequately (for example, a chest infection that worsens, a UTI that spreads to the kidneys, or an infected wound).
  • You are in higher‑risk groups: older adults, babies, people with chronic conditions (diabetes, lung disease, kidney disease, cancer), weakened immune systems, or those who recently had surgery or are in intensive care.
  • You have invasive devices like intravenous lines, urinary catheters, or breathing tubes, which can let germs into the body more easily.

But: even young, previously healthy people can develop sepsis from common infections like flu, pneumonia, or a bad skin infection, just less often.

Early signs of infection to watch

Catching and treating infections early is the best way to stop them progressing to sepsis.

Common early infection signs (before sepsis):

  • Fever or chills.
  • Cough, sore throat, or feeling like you have the flu.
  • Pain or burning when peeing, needing to pee more often, or blood in urine (UTI).
  • Red, warm, painful, or oozing skin around a cut, bite, or wound.
  • Feeling more tired than usual or “off,” especially if you’re older or already unwell.

If these symptoms are getting worse rather than better, that’s when you need a medical review to avoid sepsis.

Key red‑flag symptoms of sepsis

These are warning signs that an infection may have tipped over into sepsis and needs immediate emergency care.

In adults and older children, urgent red flags include:

  • Confusion, new slurred speech, or acting “not right” mentally.
  • Very fast breathing, struggling to breathe, or feeling severely short of breath.
  • Very fast heart rate, feeling faint, or very low blood pressure (lightheaded, about to pass out).
  • Skin that is pale, blue, grey, or blotchy, or a rash that does not fade when you press a glass on it.
  • Extreme pain or discomfort, often described as “the worst I’ve ever felt.”
  • Fever with shivering or feeling very cold; sometimes, the temperature can also be abnormally low.

For babies and young children, sepsis can be harder to spot, so emergency help is needed if they:

  • Are very sleepy, difficult to wake, or unusually floppy.
  • Have fast breathing, grunting sounds, or the skin under the ribs pulling in with each breath.
  • Have blue, pale, or blotchy skin, lips, or tongue.
  • Have a rash that doesn’t fade when pressed with a glass.
  • Feed poorly, have dry nappies, or seem unusually cold or hot.

If you notice these red‑flag signs in yourself or someone else, call emergency services immediately (999/911 or your local emergency number).

How sepsis is diagnosed in hospital

Doctors do not rely on one single test; they put together symptoms, vital signs, and lab results.

Typical steps include:

  1. Rapid assessment
    • Checking breathing rate, heart rate, blood pressure, temperature, oxygen level, and mental state.
 * A very unwell person with an infection may be treated as sepsis even before test results return.
  1. Blood tests and cultures
    • Complete blood count to look at white blood cell levels.
 * Lactate level to see if organs are not getting enough oxygen (a sign of severe sepsis).

 * Blood cultures or other samples (urine, sputum, pus) to find the germ causing the infection.
  1. Imaging
    • X‑rays or scans (like CT) to locate the infection source, such as pneumonia or abdominal infection.

How to lower your risk (practical steps)

You can’t eliminate the risk completely, but you can lower the chance that an infection turns into sepsis.

Helpful measures:

  • Keep vaccines up to date, especially for flu, COVID‑19, and pneumonia, which reduce serious infections that can lead to sepsis.
  • Clean cuts and wounds, watch them for redness, swelling, pus, or increasing pain, and seek care early if they look infected.
  • Practise good hand hygiene: wash hands regularly, especially before eating, after using the toilet, and after caring for someone who is ill.
  • Manage chronic illnesses (diabetes, heart or lung disease) and attend regular check‑ups if you’re in a higher‑risk group.
  • If you’re given antibiotics for an infection, take them exactly as prescribed and contact a clinician if you’re not improving or are getting worse.

A useful phrase many campaigns use is: “If you’re getting sicker and sicker with an infection, ask: ‘Could it be sepsis?’ ”

When to seek help, in plain terms

Seek same‑day urgent medical advice (non‑emergency line, urgent care, or your doctor) if:

  • You have an infection and are feeling much more unwell than you’d expect.
  • Your fever, pain, or breathing are getting worse, not better.
  • You’re high‑risk (older, pregnant, newborn, chronic illness, weakened immune system) and have any new significant infection symptoms.

Call emergency services immediately if you or someone else with an infection has: confusion, severe breathlessness, mottled/blue skin, a non‑fading rash, extreme pain, or feels like they might pass out.

Quick recap for “how do you catch sepsis”

  • You don’t “catch” sepsis from another person; you develop it from your own body’s reaction to an infection.
  • Any infection can lead to sepsis, especially if it’s severe, untreated, or you are in a higher‑risk group.
  • The critical thing is recognising infections early, watching for red‑flag signs, and getting urgent help if you’re suddenly much more ill than a normal infection.

Information gathered from public forums or data available on the internet and portrayed here.