What are common signs of infection?

The signs of infection primarily encompass pain, swelling, redness, and fever, which are key indicators that the body is responding to illness or pathogens. Pain often arises due to inflammation in the affected tissue, signaling that there may be an underlying infection. Swelling, or edema, typically occurs when blood vessels become more permeable in response to infection, allowing fluid and immune cells to reach the affected area. Redness is also related to increased blood flow to the area as part of the immune response, which helps fight off the infection. Fever is a systemic response that indicates the body is actively fighting an infection, as elevated temperatures can inhibit the growth of pathogens and enhance the effectiveness of immune cells.

Other signs like coughing and sneezing can relate to respiratory infections, while itching and dryness might reflect skin conditions rather than infections, and nausea and vomiting can be symptoms of various illnesses but are not specifically indicative of infection alone. Each of these alternatives presents signs that can happen in different contexts, but the combination of pain, swelling, redness, and fever is the most consistent and direct representation of an infection's presence.