Signs of wound infection to look for
The classic signs of wound infection show up in and around the wound. Look at it in good light each time the dressing is changed, and compare it with how it looked before.
- Redness or darkening of the skin that spreads outward from the wound
- Skin near the wound that feels warm
- New or increasing swelling
- Pain or tenderness that is new, worse or different
- Thick, cloudy, yellow, green or tan drainage, or clearly more drainage than before
- A new or stronger odor that remains after the wound is cleaned
- Fever, chills or feeling unwell
One sign alone does not prove infection, and only a clinician can diagnose one. Report any of these signs, especially two or more together or one that is getting worse.
Signs that are easy to miss
Older adults and people with diabetes, poor circulation or a weakened immune system may have little redness and no fever. In a wound that has been open a long time, the clues can be quieter:
- Healing that stalls, or a wound that starts to get larger
- New small openings or areas of breakdown near the wound
- Tissue that looks dull or dark, or bleeds easily when touched
- Blood sugar running higher than normal for no clear reason
- New tiredness, poor appetite or confusion
If you have diabetes, report unexplained high readings to the clinician who manages your diabetes care and to the wound care team.
What is expected early on and what is not
In the first days after an injury or surgery, a narrow rim of pink or red at the wound edges, mild swelling, some tenderness and a little thin, clear or pale yellow fluid are part of normal healing. These should ease gradually.
Infection moves in the other direction. Redness widens, pain builds, drainage thickens or you start to feel sick. Our guide to wound drainage and what it means explains colors and amounts, and the page on surgical site infections covers incisions.
When to call the treating clinician today
Do not wait for the next scheduled visit. Call the treating clinician’s office if you notice:
- Redness, warmth or swelling that is spreading
- Pus, a new foul odor or a sudden increase in drainage
- Pain that is clearly getting worse
- Fever or chills
- A wound that suddenly looks larger, deeper or darker
If you cannot reach the office and things are getting worse, go to urgent care or an emergency department. It helps to have after-hours numbers written down in advance, and our guide to building your wound care contact list shows how.
When to call 911
Some infections spread quickly into deep tissue or the bloodstream. Call 911 if the person has:
- Confusion, unusual sleepiness or trouble waking
- Fast breathing, shortness of breath or a racing heartbeat
- Fainting or severe weakness
- Shaking chills with a high fever
- Severe pain that seems out of proportion to how the wound looks
- Redness that spreads within hours, or skin turning purple, gray or black
What to write down before you call
Clear details help the clinician decide how quickly you need to be seen:
- When you first noticed the change, and whether it is getting worse
- Your temperature, and your blood sugar if you check it
- How far the redness or swelling reaches from the wound edge
- The color, thickness and amount of drainage
- Any new medications, including antibiotics started somewhere else
Our guides to telehealth and wound photos and describing wound changes to your care team can help you prepare.
What the clinician may do
The treating clinician examines the wound, decides whether it is infected and chooses the response. That may include a wound culture, blood tests or imaging, a change in local wound care, antibiotics or, for a serious infection, hospital care.
Through wound infection monitoring and follow-up, Gateway helps schedule visits with partner clinicians across Greater St. Louis and the Metro East and route results to the clinician who ordered them. Follow-up after cellulitis or an infected wound is arranged the same way.
For wound care that is not urgent, call 314-325-0126 or use the request care form, which collects contact details only. Do not wait on a web form callback for a possible infection.
Common questions
Is redness around a wound always an infection?
No. A thin rim of redness is part of early healing. Skin can also turn red and irritated from drainage sitting on it, from tape or adhesive, or from a reaction to a product. Redness that spreads, feels warm, hurts or comes with other signs is more concerning. When you are unsure, describe it to the treating clinician and let them decide.
How do infection signs look on darker skin?
Redness can be hard to see on brown or black skin. The area may look darker than the skin around it, purplish or gray, or shiny and tight. Rely on touch and symptoms as well as color: warmth, firmness, swelling, tenderness and new pain. Comparing with the same spot on the other side of the body can help.
What does a red streak leading away from a wound mean?
A red line running from a wound toward the body can mean an infection is traveling through the lymph vessels under the skin. Call the treating clinician right away, or go to urgent care or an emergency department if you cannot reach them. Call 911 if the streak comes with fever, chills, confusion or feeling very ill.
Should I put antibiotic ointment on a wound that looks infected?
Do not add an ointment, cream or cleanser that is not part of your plan without asking first. Some products irritate the skin, cause allergic reactions or interfere with the dressing the clinician chose, and an ointment cannot treat an infection that has spread into the skin. Call the treating clinician, describe what you see and follow their instructions.
Related pages
General information to help you talk with your own clinician. It is not medical advice, and the treating clinician makes every clinical decision. For a medical emergency, call 911.
Updated October 2026