Conjunctivitis (kon-jung-tih-VY-tis), often called pinkeye, is an inflammation of the conjunctiva (kon-jung-TIE-vuh), the thin membrane that lines the inside of the eyelids and covers the surface of the eyeball. Conjunctivitis can be caused by viruses, bacteria, allergies, or chemical irritation.
for searching the Internet and other reference sources
What Is Conjunctivitis?
Conjunctivitis, is an inflammation of the thin membrane that lines the inside of the eyelids and covers the white surface of the eye. The inflammation can produce redness, burning, or itching of the eyes and sometimes a discharge. Bacterial or viral infections most often cause conjunctivitis. Many different bacteria can be the culprit, most commonly Streptococcus pneumoniae (strep-tuh-KAH-kus nu-MO-nye), Haemophilus influenzae (he-MOH-fih-lus in-floo-EN-zuh), and Staphylococcus aureus (stah-fih-lo-KAH-kus ARE-ree-us). Infections with adenoviruses * and influenza viruses are common causes of conjunctivitis. About 80 percent of all cases of conjunctivitis result from viral or bacterial infection.
* adenoviruses (ah-deh-no-VYruh-sez) can produce a variety of symptoms, including upper respiratory disease, when they infect humans.
* parasites (PAIR-uh-sites) are organisms such as protozoa (one-celled animals), worms, or insects that must live on or inside a human or other organism to survive. An animal or plant harboring a parasite is called its host. Parasites live at the expense of the host and may cause illness.
Rarely, parasites * and fungal infections can cause conjunctivitis. The condition also can stem from various allergies, irritants, chemicals, and pollutants. Reactions to smoke, dust, makeup, contact lenses, and pollen all can produce symptoms in some people. The sexually transmitted diseases chlamydia * and gonorrhea * , which can be passed from infected mothers to their babies during birth, are the most common causes of conjunctivitis in newborns. These two diseases can lead to conjunctivitis in adults as well. Conjunctivitis usually does not cause problems with vision.
How Does Conjunctivitis Spread and
Who Gets It?
Conjunctivitis, especially of viral origin, typically is seen in children and adults who are caregivers of children, such as parents or day-care workers. Bacterial conjunctivitis is less common in healthy older children and adults. Both the bacterial and viral forms of the condition are contagious. The germs that cause conjunctivitis may be present in nasal secretions and in the discharge from the eyes. People can become infected simply by touching the face of someone with the disease and then rubbing their own eyes without first washing their hands. Sharing contaminated towels or eye makeup also can spread the infection. Infectious conjunctivitis can spread quickly through child-care and school settings and among members of the same family. Bacterial conjunctivitis can remain contagious until treatment with antibiotics is started. The viral form is usually contagious before the symptoms appear and for as long as symptoms, including any discharge from the eye, last.
What Are the Signs and Symptoms
The first symptoms typically appear within a few days or up to a week after infection. A person may feel discomfort, a gritty sensation under the eyelids, or a feeling that there is something in the eye. Redness develops in the eye, and the eyelids may swell. Bacterial infections usually produce a thick yellowish or greenish discharge. When the person wakes up in the morning, the eyelids might stick together as the result of dried discharge. In viral conjunctivitis, the discharge is often thin, watery, and clear. Viral infections are more likely to affect both eyes and can be accompanied by other symptoms of viral infection, such as cold or flu symptoms.
* chamydia (kla-MIH-dee-uh) are microorganisms that can infect the urinary tract, genitals, eye, and respiratory tract, including the lungs.
* gonorrhea (gah-nuh-REE-uh) is a sexually transmitted disease (STD) spread through all forms of sexual intercourse. The bacteria can also be passed from an infected mother to her baby during childbirth. Gonorrhea can affect the genitals, urethra, rectum, eyes, throat, joints, and other tissues of the body.
How Is Conjunctivitis Diagnosed?
Eye discharge and inflammation (redness) of the conjunctiva are the hallmarks of conjunctivitis. The doctor also will ask whether the person has had any recent contact with someone with conjunctivitis and will examine the eyes, making sure the person's vision is normal. Sometimes the doctor will swab the inside of the eyelids to obtain fluid for laboratory testing, to determine the type of infection. This is more likely to be done in newborn babies or someone at risk of a sexually transmitted disease, such as chlamydial infection or gonorrhea.
How Do Doctors Treat Conjunctivitis?
Treatment depends on the cause of conjunctivitis. If bacterial conjunctivitis has been diagnosed, antibiotic eyedrops usually are prescribed for about a week. An antibiotic ointment is used for babies. Viral conjunctivitis disappears by itself and does not typically require treatment. (One exception is conjunctivitis caused by herpesvirus * infection, which is treated with antiviral eyedrops.) Over-the-counter pain relievers, such as acetaminophen (uh-see-teh-MIH-noh-fen), and warm compresses placed over the eyelids several times a day may ease the discomfort. Conjunctivitis usually clears up within a week. Cases of viral conjunctivitis can take longer to resolve than bacterial conjunctivitis.
Are There Complications?
Complications of conjunctivitis are rare. In newborns, untreated gonorrheal infection of the conjunctiva can cause a spreading infection of the eye that can lead to blindness. A few viruses cause conjunctivitis that affects deeper parts of the eye, resulting in keratitis (kare-uh-TY-tis), an inflammation of the cornea * that causes changes in vision and sometimes permanent scarring of the cornea. Trachoma (truh-KO-mah), a type of chlamydial conjunctivitis seen in developing countries, also can lead to blindness.
Can Conjunctivitis Be Prevented?
The best way to prevent infectious conjunctivitis is to wash hands frequently, especially after touching the face of someone who has the infection. It is a good idea for people with infectious conjunctivitis to wash their hands often to avoid spreading the infection. It is also wise not to share makeup; disposable items, such as paper towels and cotton balls; or towels. Washing towels and clothing in hot water can disinfect them.
* herpesvirus (her-peez-VY-rus) is a member of a family of viruses that can store themselves permanently in the body. The family includes varicella virus. Epstein-Barr virus, and herpes simplex virus.
* cornea (KOR-nee-uh) is the transparent circular layer of cells over the central colored part of the eyeball (the iris) through which light enters the eye.