Terry D. Connell knows a lot about the immune system: He's a University at Buffalo, N.Y., professor in the Department of Microbiology and Immunology in the School of Medicine and Biomedical Sciences who conducts research on new vaccines for diseases, such as tuberculosis.

But his academic credentials are only part of the reason that he believes everyone over the age of 60 should get a shingles vaccination. The other part is his personal experience with shingles.

"It was the most debilitating and painful thing I'd ever experienced," says Connell, who had shingles about a decade ago. "At times, it was so painful, I couldn't have a bed sheet touch my body."

Connell had symptoms for two months. He developed a rash on the small of his back and blisters on the bottom and top of one of his feet. "For a few days, it was too painful to walk," he recalls, noting that once he could walk, he had to use a cane for about two weeks.

"I was lucky," says Connell. "The pain in some individuals can be so severe that physicians have to prescribe antidepressant drugs."

And in some cases, shingles can leave the individual with lifelong pain, caused by a post-shingles syndrome termed "post-herpetic neuralgia." According to the U.S. Centers for Disease Control and Prevention, at least 13 percent of people over 60 will develop post-herpetic neuralgia after having shingles.

"Shingles are caused by varicella zoster, the same virus that causes chicken pox," Connell explains. "Once the virus infects an individual, often as a child, and the primary symptoms of chickenpox subside, the virus 'hides out' in the nerve cells of the body. Those hidden viruses can reactivate at any point in life to produce shingles."

Nearly one in three Americans will develop shingles, according to the CDC. The chance of developing shingles becomes more likely as people age.

"That's because our immune systems weaken as we age," says Connell. "With the weakened immune system, we cannot keep the 'hidden' virus under control."

Vaccination is recommended for everyone over the age of 60. According to the CDC, vaccinated individuals can still develop shingles, but the vaccine will likely make the pain less severe and should shorten the length of the outbreak.

Shingles starts as a rash usually on only one side of the body, commonly appearing in the shape of a stripe, often around the abdomen, but it can occur on any part of the body, including on the face, eyes, or mouth. Before the rash forms, there often is pain and itching or tingling. The disease often is accompanied by fever, headache, chills, and upset stomach.

Shingles can strike out of the blue, Connell says, even if you are perfectly healthy, as he was.

"I had just added weight lifting to my fitness routine and one day after I worked out, my back started hurting," Connell says. "I thought, 'Oh, it's from the workout.'"

A few days later, however, the pain became much worse. Connell worried that it might be a herniated disk.

"I could barely get out of bed," he recalls. "I was sure it was my back. I managed to get an appointment with UB Orthopedics and Sports Medicine. As I was getting out of the car and placed my foot on the pavement, a sharp pain zipped from my foot all the way up my leg. I stepped out of my shoe and saw the blisters. Right away ... I suspected it was shingles."

He realized that he probably needed to see his primary care physician. But, as he was already at UB, he went to the appointment. When the sports medicine physician couldn't find anything wrong with his back or muscles, Connell deliberately revealed the blisters on his foot. "He realized what I had already surmised: shingles."

The doctor summoned UB medical residents in the clinic so that they could see how symptoms presenting as one medical issue may turn out to be something different.

Shingles can be transmitted through contact with the lesions that develop. Most people only have one episode of shingles, Connell says.