Cellulitis is not a sexually transmitted infection (STI). The infection is a common bacterial skin condition that affects millions of people each year in the United States. Instead of being passed through sexual contact, cellulitis is an opportunistic infection that occurs when common bacteria enter the body through a break in the skin barrier.
What Exactly is Cellulitis?
Cellulitis is a bacterial infection affecting the dermis and the subcutaneous tissues, which are the deeper layers beneath the skin’s surface. The infection is typically caused by common bacteria, such as Streptococcus or Staphylococcus species, which often live harmlessly on the skin.
The infection manifests with a set of characteristic local symptoms at the site of entry. These signs include an area of skin that becomes red or discolored, swollen, noticeably warm to the touch, and tender or painful. The affected area often expands rapidly, and the skin may appear tight, glossy, or pitted, sometimes resembling the texture of an orange peel. If left untreated, the infection can spread into the lymph nodes and the bloodstream, which has the potential to become life-threatening.
How Cellulitis is Actually Contracted
Acquiring cellulitis relies entirely on a breach in the protective outer layer of the skin, known as the epidermis, that allows bacteria to colonize the underlying tissues. This entry point is known as the portal of entry, and it has no direct connection to sexual activity for the vast majority of cases.
Specific events and conditions frequently create this necessary breach in the skin barrier. Simple cuts, scrapes, surgical incisions, or even minor insect bites can provide a pathway for bacteria to enter. Chronic skin conditions also significantly increase risk, as issues like athlete’s foot, eczema, or psoriasis often cause microscopic or visible cracks in the skin. Any condition that impairs skin integrity or compromises the immune system, such as lymphedema or diabetes, increases susceptibility to this opportunistic infection.
Understanding Contagion and Risk
Cellulitis is not generally considered contagious in the way that viral infections or STIs are, because the infection is contained within the deeper layers of the skin. The intact outer skin layer acts as a barrier, preventing the bacteria from being easily transmitted to another person. Therefore, person-to-person spread is rare and would only occur if an open wound on one person’s skin came into direct contact with the active, infected tissue of another.
Prompt medical attention is necessary if symptoms like spreading redness, warmth, or pain are noticed, as this bacterial infection requires antibiotic treatment. Failure to treat cellulitis quickly can lead to the infection spreading into the bloodstream, potentially causing systemic illness. A healthcare provider will typically prescribe oral antibiotics for localized infections, but more severe cases may require hospitalization and intravenous antibiotics to clear the infection effectively.