If you happen to see a blister on the tip of your nose, get yourself to the doctor right away. It could be shingles, and it could cost you your sight. More on that in a moment.

If you’ve never had shingles, consider yourself lucky. Those who have say it’s one of the most painful experiences of their lives. Shingles involves pain, itching, or tingling of the skin, with a painful rash of blister-like sores, usually on one side of the body…often on the torso or face. Nearly 1 in 3 people in the U.S. will develop shingles, according to the CDC. Shingles is caused by the same virus that causes chickenpox -- varicella zoster virus. After people recover from chickenpox, the virus remains dormant in the body and can reactivate many years later, leading to shingles. Nearly all Americans born before 1980 have had chickenpox, the CDC says. Besides the rash, there can be headache, chills, fever and upset stomach. About 10% of those who get shingles have persistent nerve pain for months or even years after being affected.

            The good news is there’s a new vaccine for anyone 50 or older that can prevent shingles. In the video, Dr. Dan Aires, head of Dermatology at The University of Kansas Health System, describes shingles and how it occurs. He also explains the differences between the old and new vaccines…and how the new two-shot vaccine regimen raises the effectiveness from about 50 percent with the old vaccine to 90 percent with the new. He also warns that a blister on the tip of the nose is a medical emergency…it could be a sign the virus may be invading the area around the eyes…leading to blindness.