**Core Concept**
Impetigo is a highly contagious superficial skin infection caused by Staphylococcus aureus or Streptococcus pyogenes. It typically presents as crusted, golden-colored lesions on the face, especially around the nose and mouth.

**Why the Correct Answer is Right**
Impetigo spreads through direct contact with an infected person's skin or by contaminated objects. The infection can also spread through the air when an infected person coughs or sneezes, releasing bacteria into the environment. The causative bacteria produce toxins that lead to the characteristic golden crusting and pus-filled lesions.

**Why Each Wrong Option is Incorrect**
**Option A:** Impetigo is not typically associated with lymphadenopathy (swollen lymph nodes). Impetigo is a localized skin infection, and systemic symptoms are rare.
**Option B:** Impetigo is not a serious life-threatening condition, unlike necrotizing fasciitis, which is a more severe and potentially deadly infection. Impetigo is contagious but not life-threatening.
**Option C:** Impetigo is not primarily treated with antiviral medications. Instead, topical or oral antibiotics are used to target the bacterial infection.
**Option D:** Impetigo is not caused by a fungal infection. It is caused by either Staphylococcus aureus or Streptococcus pyogenes bacteria.

**Clinical Pearl / High-Yield Fact**
Impetigo is highly contagious and can spread easily in crowded areas, such as schools or daycare centers. It is essential to practice good hygiene, including frequent handwashing, to prevent the spread of impetigo.

**Correct Answer:** C. Impetigo is not primarily treated with antiviral medications.