Warning signs of wound infection are not the same for every wound, because they depend on the kind of wound. Rather than flatten them into one list, here are the signs for each.
For a pressure sore, contact your provider right away if you develop blisters, an open sore, or show any signs of infection, such as a foul odor from the sore, pus coming out of the sore, redness and tenderness around the sore, skin close to the sore that is warm or swollen, or fever.
For a diabetic foot ulcer, the signs are redness, increased warmth, or swelling around the wound; extra drainage; pus; odor; fever or chills; increased pain; and increased firmness around the wound. There’s also a separate instruction: contact your provider if your foot ulcer is very white, blue, or black.
For an ischemic ulcer, the signs are redness, increased warmth, or swelling around the wound; more drainage than before or drainage that is yellowish or cloudy; bleeding; odor; fever or chills; and increased pain.
For a surgical incision, contact your surgeon if there is more redness or pain, swelling or bleeding, if the wound is larger or deeper, or if it looks dried out or dark. Also contact your surgeon if drainage increases or becomes thick, tan, green, or yellow, or smells bad.
For chronic wounds in general, the signs are increasing pain, redness spreading around the wound, swelling or warmth, pus or a change in the wound fluid, bad smell, and fever or feeling unwell.
Taken together, these lists overlap a lot: redness, warmth or swelling, more drainage or pus, odor, more pain, and fever show up in nearly all of them. But the differences are real, and the instructions that go with each list are for that wound. If you have a wound, the list to use is the one for your kind of wound, and the person treating it can tell you which that is.