The scourge of shingles

Column by Dr. Tim Moser

By Dr. Tim Moser, Denver House Calls in Denver
Posted

Jose has been experiencing persistent pain on his mid back area for several days. As he was getting ready for bed, his wife noted a small cluster of blisters on his mid back, on the right side. The area looked very similar to a series of insect bites, but this was the winter and no bugs had been seen in the home. That night Jose developed a mild fever, and an increase in the back pain made him sleep poorly. The following morning, his wife phoned the doctor to make an appointment.

During the examination, the doctor asked if Jose had been infected with chickenpox as a child. Jose remembered the infection when he was 10 years old. The doctor diagnosed shingles, and explained what caused the condition. Medication was prescribed to treat the infection and the pain. Within days, Jose had made a complete recovery.

The medical condition commonly known as shingles is also referred by the medical name herpes zoster or just zoster. It becomes more common as a person ages, and can cause significant side effects, to include blindness or persistent pain that could last a lifetime.

The virus that never leaves the body.

If you were born before the year 1990 chances are good you were infected with chickenpox as a a child (also known as varicella). That is because the vaccine developed to prevent chickenpox was not licensed in the United States until 1995. Chickenpox is described as one of the "usual childhood diseases" by doctors - a self-limiting infection that in most persons did not cause lasting harm. In fact, sometimes children were intentionally exposed to their peers who were infected with chickenpox in an attempt to cause an infection. Since the chickenpox virus is spread through the air by tiny droplets following a cough or sneeze, it is easy to spread from person to person with casual contact. Once infected by chickenpox, then a good immunity against re-infection develops and lasts a lifetime.

There is a dark side to the chickenpox virus, however. Since it belongs to the herpes family of viruses, chickenpox infection leads to a very interesting change in the body. During the infection process, the virus finds its way to the nervous system. In the nerve cells that exit the spinal cord, the virus literally splits openthe portion of the nerve cell that contains the DNA. A copy of the virus DNA is then inserted into the DNA of the infected person's nerve cell, where it remains for life.

Those that have been infected with chickenpox (or any herpes infection, for that matter) carry in their DNA a copy of the virus that is always lurking in the background, ready to emerge when it is least expected. Thus, the phrase "Never trust a herpes virus" was born!

What causes shingles?

If a person has been infected with chickenpox in the past, they run the risk of developing shingles in the future. This simple fact places millions of Americans at risk of shingles, especially as they age. Shingles is caused when the chickenpox virus that has now become a part of your DNA decides to re-activate itself. Usually, a single nerve is affected. This means shingles affects only one side of the body. The nerves affected are usually the sensory nerves, which as the name implies are responsible for providing sensation to the skin. As the virus awakens from its dormant slumber and replicates itself countless times, it slowly travels down the entire length of the nerve until it reaches the skin. Once the destination is reached, a rash develops that appears like small water blisters. The surrounding area is red, and pain is usually present. Any area of the body can be the target of a shingles infection, but the single most common is the lower chest and back, along the lower margin of the breast.

Symptoms of shingles

The most common symptom of a shingles infection is pain. This may come several days before the rash appears, making the diagnosis extremely difficult early on in the process. Some of those with shingles experience only an intense itching in the area.

Since the virus is following the length of a nerve, only the area of skin supplied by that particular nerve is affected. This translates into a band several inches in width that starts at the spine, and curves around the body where it ends in the front midline. If an arm or leg is affected, the band will start near the spine and may extend to the hand or foot. In the face, one of three zones will be affected. This may be very serious if the infection spreads across an eye.

Complications

Because the reactivated chickenpox virus is traveling down a nerve, damage to the affected nerve is always a possibility. The symptoms of nerve pain following shingles is called post herpetic neuralgia. This is truly as bad as it sounds. Intermittent, severe pain can appear throughout the day and night, and can be debilitating. Since nerves heal much slower than most other pats of the body, the damage can persist for moths, or even years. Treatment involves the use of drugs that target the nerves, such as Nortriptylline or Gabapentin. Sometimes narcotics are needed.

Another serious complication of shingles is blindness. If the infection involves the face and comes across the eye area, the cornea can become scarred and permanently damaged. To prevent this, any shingles infection affecting the face should probably prompt an examination by an eye doctor.

Treatment and prevention

The hallmark of minimizing the side effects of a shingles infection are early detection and treatment. If the infection is recognized within 72 hours of onset, anti viral medication can be prescribed which will stop the replicating virus in its tracks. Pain medication may also be used.

The risk of shingles may be reduced in those persons over the age of 65 with the zoster vaccine. A single immunization will help boost the body's immune system and will help reduce the chances the virus can become active again.

Is shingles contagious?

Persons with active shingles cannot give shingles directly to another person. However, the skin rash associates with shingles does contain chickenpox virus. The virus is not airborne in shingles, however, so direct skin to skin contact with another person would be required to transmit the virus. If the other person has never had chickenpox, or has not had the chickenpox (varicella) vaccine, then a person could get chickenpox from another person with shingles. Once the rash crusts over, there is no risk of transmitting the virus.

Want more information about shingles?

http://www.mayoclinic.com/health/shingles/DS00098

 

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001861/