Which sign is commonly associated with strep throat?

Swollen lymph nodes in the neck are a commonly associated sign of strep throat, which is caused by infection with the bacteria Streptococcus pyogenes. This condition typically presents with the body's immune response to the infection, leading to lymphadenopathy, or swollen lymph nodes. The lymphatic system plays a crucial role in fighting off infections, and when the throat is infected, the lymph nodes in that area often become enlarged and tender, as they work to filter out the bacteria and produce immune cells.

In contrast, the other signs listed do not typically indicate strep throat. Skin irritation is more commonly associated with allergic reactions or other skin conditions, chronic cough is often a symptom related to respiratory issues such as a cold or allergies rather than a throat infection, and ear pain may indicate an ear infection or other condition but is not a primary symptom of strep throat. Therefore, the presence of swollen lymph nodes specifically aligns with the body’s response to a strep throat infection.