Pink eye, medically known as conjunctivitis, is an inflammation of the transparent membrane that covers the white part of the eye and lines the inner surface of the eyelids. It often causes a reddish or pink appearance. Many wonder how quickly symptoms emerge after exposure.
Understanding Pink Eye
Pink eye can arise from various sources, primarily categorized into viral, bacterial, and allergic types. Viral conjunctivitis is often caused by the same viruses responsible for the common cold. Bacterial conjunctivitis results from bacterial infections and can sometimes be more severe. Both viral and bacterial forms are infectious. Allergic conjunctivitis stems from the body’s reaction to allergens like pollen or dust mites and typically affects both eyes.
Onset of Symptoms by Type
The time it takes for pink eye symptoms to appear varies depending on its cause. For viral conjunctivitis, symptoms emerge within one to three days after exposure, though this period can sometimes extend up to twelve days. Viral pink eye often begins in one eye and then spreads to the other within a few days.
Bacterial conjunctivitis has a shorter incubation period. Symptoms manifest within 24 to 72 hours following exposure to the bacteria. This type can also start in one eye and potentially affect the other.
Allergic conjunctivitis does not involve an incubation period. Symptoms appear immediately or within minutes to a few hours after contact with an allergen.
Recognizing Early Signs
Early indications include redness in the white of the eye, often accompanied by a feeling of irritation or a gritty sensation, as if something is in the eye. Itching is also a common symptom, particularly with allergic forms.
Tearing may increase, and a discharge from the eye can develop. This discharge can be watery with viral infections, or thicker and yellow-green with bacterial infections, potentially causing eyelids to stick together, especially upon waking. Swollen eyelids and increased sensitivity to light are additional signs.
Contagion and Transmission
Viral and bacterial forms of pink eye are highly contagious, spreading through direct or indirect contact with eye discharge. This occurs by touching contaminated surfaces, then eyes, or through close personal contact like handshakes. Coughing and sneezing also contribute to its spread.
A person with viral pink eye can remain contagious as long as symptoms are present, up to 10 to 14 days. Bacterial pink eye is contagious as long as there is discharge from the eye, or until 24 hours after antibiotic treatment has started. Allergic conjunctivitis, however, is not contagious.