What are Koplik spots a symptom of?

Koplik spots are specific to measles and serve as an important clinical sign indicating this viral infection. They are small, bluish-white lesions that appear on the buccal mucosa, typically just opposite the molars, and usually manifest a few days before the characteristic measles rash appears. Their presence is often considered pathognomonic for measles, which aids in the clinical diagnosis of the disease.

In the context of other viral infections listed, chickenpox presents with a vesicular rash rather than oral lesions, German measles (rubella) does not produce Koplik spots and involves a different set of symptoms, and mumps primarily affects the salivary glands, often presenting with swelling rather than these specific oral signs. Thus, the connection of Koplik spots to measles reinforces their role as a diagnostic feature for that specific condition.