American Board of Dental Examiners (ADEX) Dental Hygiene Licensing Examination 2025 - Free Dental Hygiene Practice Questions and Study Guide

The viral infection that presents similar symptoms to rubella and is distinguished by the presence of Koplik spots is measles. Measles, also known as rubeola, typically starts with symptoms such as fever, cough, runny nose, and conjunctivitis, which can be similar to the symptoms of rubella. However, a key clinical feature that sets measles apart is the appearance of Koplik spots. These spots are small, white lesions that appear inside the mouth, usually on the buccal mucosa, and they often develop a couple of days before the characteristic measles rash appears.

The presence of these spots is a classic sign and serves as an important diagnostic tool for healthcare providers. In contrast, the other infections listed do not share this distinct feature and exhibit different clinical presentations. Chickenpox is characterized by a vesicular rash and itching, while scarlet fever presents with a red rash and is often associated with strep throat. Herpes simplex virus causes localized lesions and ulcers, but lacks the systemic symptoms and Koplik spots seen in measles. Hence, distinguishing measles from rubella is made easier by recognizing the presence of Koplik spots, solidifying measles as the correct answer.