What's Happening With Bob Costas' Eye and How You Can Avoid It

Bob Costas put forth an Olympian effort, but his red, swollen eyes have gotten the best of him. For the first time since 1988, the veteran sports anchor will cede his his nightly Olympics hosting duties to Matt Lauer while his mysterious infection clears.

It’s not clear how Costas’ eyes got so inflamed – but pink eye, or conjunctivitis, is the most common infection among U.S. children and adults. It’s caused by both bacteria like staph and strep, and viruses like the cold virus (which means it is highly contagious). It can also be caused by allergies or chemicals. Pink eye causes red, inflamed, and swollen conjunctiva, or the membranes that cover the white parts of the eyes. Infections are common wherever people are in close contact: day care centers, classrooms, college dorms and work places. Worried about your risk? Here’s what you need to know.

How do I avoid getting eye infections?

There’s no way to foolproof yourself, especially if you have an allergic reaction to something you touch or something that you are exposed to in the air.

But the best way to protect against the bacteria and viruses that trigger infections is to wash your hands and not share things like washcloths, pillows, sheets or eyewear.

If someone near you is already infected, make sure you avoid touching anything that has been near their eyes. It’s also a good idea to disinfect common areas such as bathroom and kitchen surfaces.

How do I know if my eyes are infected?

Infections can cause a runny discharge that can dry to form a crusty layer, making it hard to open your eyes in the morning. You may also feel some pain and itchiness in your eyes. Use a disposable paper towel and warm water to clear away any residue, or, if you use a towel, wash it thoroughly afterward.

Costas appeared on air Thursday with one swollen pink eye, but as of Monday evening, this is how he looked:

How long do infections last?

Viral infections can cause redness and itching for up to a week, while other reactions, particularly those caused by allergic responses to chemicals or smoke, can last as long as three weeks or more.

What’s the best treatment?

For viral infections, there is no real treatment other than artificial tear drops, which can help to relieve itchiness and pain. Doctors may prescribe antibiotics for bacterial infections, which can clear up pink eye in several days. See your doctor to determine which treatment is appropriate for your case.

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