Chickenpox is a well known infection mainly occurring in children. However, the same virus that causes chickenpox can cause another infection mainly in adults. This condition is known as shingles or herpes zoster and any person who had chickenpox earlier in life is at risk of developing shingles. It is more likely to occur in older adults or younger adults with a weakened immune system but is rare in children.
How To Spot Shingles
There is no certain way of determining who will get shingles or not among people who had chickenpox earlier in life. Even when it does arise the early symptoms of shingles can be non-specific and vague, such as fever, loss of appetite, fatigue, light sensitivity and a headache. However, this does not occur in every person who develops shingles. These early symptoms are then followed by tingling, itching and pain before the shingles rash appears.
The rash can then clear up within a few weeks while pain and itching may persist for a long period of time. The characteristic sign of shingles is that the symptoms occur on certain demarcated areas. These areas or stripes on the head or torso are known as dematomes. It is the areas supplied by a single nerve. Since the virus lays dormant within nerves and then reactivates at some point, it affects specific dermatomes supplied by the affected nerve.
Where does shingles come from?
Shingles is also known as herpes zoster. It is caused by the varicella zoster virus which is the same virus that causes chickenpox. A person would had to have chickenpox earlier in life in order to develop shingles. The chickenpox virus (varicella zoster) can remain dormant in the nerves (dorsal root of the sensory ganglia) for years and decades. The viral particles do not cause any disease during this time as the immune suppresses it. With shingles, the virus causes inflammation of the nerves and may even lead to death of nerve cells.
However, when there is a weakening of the immune defenses then the virus can become reactivated. This weakening can occur for various reasons like with stress, diseases that lower the immune system such as HIV and AIDS, using treatments that suppress the immune system like anti-rejection drugs after a transplantation as well as with certain cancer treatments. The elderly are most commonly affected with shingles.
Is shingles contagious?
Yes. Shingles is contagious in that people who have never had the chickenpox or the vaccine can become infected. However, the unprotected person will develop chickenpox and not shingles. This transmission mainly occurs through direct contact with the rash but can also occur through respiratory droplets. Shingles is not as contagious as chickenpox despite the same virus being responsible.
Read more on shingles facts.
What are the signs of shingles?
The signs and symptoms of shingles usually appears on one side of the body (unilateral) and only on one dermatome (dermacated area). However, it can at times occur on more than one dermatome on the same side of the body or on both sides of the body (bilateral). This is rare and usually shows severe immune suppression like in AIDS. Sometimes shingles may affect many parts of the body simultaneously. This is known as disseminated herpes zoster and once again it is an indication of severe immune suppression.
Pain, Itching and Other Sensations
Pain,burning, itching, tingling and even numbness may occur on the affected area. However, pain is the most commonly reported sensation. It may vary in nature from a muscular ache to a burning, throbbing or stabbing pain. Furthermore the pain can vary from mild to severe. Usually the area is tender to touch and the pain can change in nature and intensity over time.
Rash and Blisters
A rash with blisters typically appears after the pain starts. Usually there is a delay of a few days between when the pain starts and the onset of the rash with blisters. This rash is reddish in nature with tiny fluid-filled vesicles. Eventually the vesicles rupture and crust over but the redness of the skin persists. In rare cases there may be symptoms like pain and numbness with no rash.
Read more on shingles pictures.
Enlarged Lymph Nodes
Enlarged lymph nodes (lymphadenopathy) may be noticed with the onset of pain or thereafter. It is usually isolated to the lymph nodes in and around the affected region.
Weakness and Paralysis
Shingles usually affects the sensory nerves leading to abnormal sensations and it affects the overlying skin. However, in some instances there may be involvement of motor nerves (nerves that control muscles). This can lead to weakness and paralysis of the muscles of the face, eyes, limbs, abdomen, bladder or other areas with associated symptoms.
Throat problem are also uncommon in shingles but if certain nerves are affected it can lead to problems with swallowing (dysphagia) and voice (dysphonia). Difficulty breathing may not be a throat problem but an indication that the phrenic nerve that supplies the diaphragm is affected. This is also rare.
Ear problems (herpes zoster oticus) are also rare in shingles but can occur if certain cranial nerves are affected. It may lead to ear pain, vescicles on the outer ear and even progress to hearing loss. There may also be simultaneous throat problems and facial rash. This is known as Ramsay Hunt syndrome.
Another uncommon occurrence in shingles is involvement of the eye. It is known as herpes zoster opthalmicus. There is a painful rash on the forehead and eyelid with eye pain, light sensitivity and sometimes visual disturbances.
Signs and symptoms beyond the abnormal sensation like pain and rash on the affected area is rare. However, these other signs and symptoms may arise when other spinal or cranial nerves are affected. Shingles can sometimes even affect the brain, gut and airways. Most cases are not this severe. As the rash clears, the pain can persist sometimes for months and years. This is known as postherpetic neuralgia.