Conjunctivitis causes
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Template:Conjunctivits
Overview
Causes
Conjunctivitis is most commonly caused by viruses, often adenovirus, but many other factors can lead to its occurrence. Other causes include:
- Allergies (allergic conjunctivitis)
- Bacteria
- Certain diseases
- Chemical exposure
- Chlamydia
- Fungi
- Parasites (rarely)
- Use of contact lenses (especially extended-wear lenses)
Conjunctivitis is spread from person-to-person by:
- Direct contact with the infected person’s eye drainage or drainage from the person’s cough, sneeze, or runny nose.
- Indirect contact with objects that may have the infected person’s drainage on them (e.g. eye makeup applicators, towels, shared eye medications).
- Contact with the infected person’s fingers or hands which may contain the virus or bacteria.
Newborns can be infected by bacteria in the birth canal. This condition is called ophthalmia neonatorum, and it must be treated immediately to preserve eyesight. Additionally, neonatal conjunctivitis is a red eye in a newborn caused by irritation, a blocked tear duct, or infection.