Herpes Zoster and Chickenpox

What is herpes zoster caused by?

Herpes zoster (shingles, latin cingulus, greek zōstēr, هربس) is a viral infectious dermatological disease caused by varicella zoster virus, it is characterized by painful dermal rash (skin rash) with blisters affecting one side of the body and presenting in a form of a stripe (a belt like appearance), that is to say herpes is usually limited to an area (involvement of the upper trunk is common).

Herpes zoster is more frequently seen in adults over 50

What is chickenpox caused by?

Chickenpox (varicella) is a common shot-lived acute viral disease that affects children and adulterants (young people), it is caused by an initial infection with varicella zoster virus. chickenpox lasts few days (3-4), after recovery from chickenpox the virus is stored in the nerve cell bodies and less frequently in non neuronal satellite cells of cranial nerve, dorsal root or autonomic ganglion in the body in its latent form as a deactivated virus.

About 200,000 cases of varicella are reported annually in the united states

How do you get shingles?

In most cases, shingles is caught from other humans (sick people and VZV carriers).

How can shingles be transmitted and can shingles be spread to others?

Shingles is usually transmitted by direct contact with blistering rash.

How long are you considered contagious with shingles?

Rash usually appears 1-5 days after the tingling or burning sensations. A few days later, the rash will transform into fluid-filled blisters. About 7 -10 days after that (after three to five days ), wet blisters dry up and harden into a scab (crust over). The person is no longer contagious once the rash has crusted over.

What disease is caused by reactivation of the chickenpox virus?

In 50% of patients with latent varicella, varicella zoster virus reactivates and break out of nerve cell bodies and travels all the way down through nerve axons to cause shingles viral infection of the skin limited to a dermatome (an area of skin supplied by one spinal nerve) corresponding to the segment or region of the affected nerve. In most cases, this usually happens years after the initial chickenpox infection.

After breaking through and affecting a dermatome the virus spreads from one or more ganglia along nerves causing painful rash that usually heals within two to four weeks while nerve pain and especially the facial nerve pain, acoustic nerve pain or dorsal nerve pain may persist for months or years thereafter, a condition called post-herpetic neuralgia.

What is the incidence rate of herpes zoster?

The incidence rate of herpes zoster (shingles) is about 3.9–11.8 per year per 1,000 individuals among elderly people (especially those older than 65 years), shingles breakouts all over the world and effects all people regardless of the race, origins or cultures backgrounds.

What is the incidence rate of herpes zoster in the us?

Before the availability of the varicella vacine, the incidence rate of shingles was about 15 per year per 1,000 population in the United States (about 3.8 million cases of chickenpox occurred each year).

Symptoms and signs

What is the incubation time of shingles and how long does it take for a person to get shingles?

The incubation period of varicella zoster virus ranges from 2 to 3 days. However, in most cases, it usually ranges from 14 to 16 days.

What are the symptoms of shingles and how long does shingles last?

The earliest manifestations or symptoms of shingles are the flu like symptoms including fever, headache, and weakness or malaise followed by sensations of mild to extreme pain, itching, oversensitivity, or pins and needles, tingling, burning and numbness, these flu like symptoms last for about three weeks. Most cases of herpes zoster last 3-5 weeks.

This initial phase is followed by the appearance of skin rash on the face, eyes (involving the orbit of the eye and occurring in approximately 10–25% of all cases, it is called herpes zoster ophthalmicus), ears (causing hearing troubles and rotational dizziness or vertigo, it is called herpes zoster oticus, or ramsay hunt syndrome type ii,), pain and rash most commonly occur on the torso though shingles may affect any part of the body, the rash forms a belt like pattern and is limited to one side of the body (it does not cross the mid-line).

Rash appears similar to the first appearance of hives and changes are limited to the affected dermatome. It develops from a papule and becomes vesicular, forming small blisters filled with pus (serous exudates and blood), as the low-grade fever and general malaise continue. The vesicles fill with blood and crust over within ten days and usually the crusts fall off without leaving a trace as the skin heals, but sometimes and after severe blistering, scarring and discoloration of skin may remain permanently.

Diagnosis

How to diagnose shingles?

Visual inspection

Herpetic rash acquire a strip-like pattern and can be easily identified.

Lab tests

Diagnosis can be confirmed by real-time PCR that shows 100% sensitivity and specificity.

Treatment

How to treat shingles?

Antiviral drug treatment can reduce the severity and duration of herpes zoster if the treatment is started within 72 hours of rash appearance, the optimal course of treatment extends from seven to ten days.

What medication is used to treat shingles?

Acyclovir is the standard treatment for herpes zoster, but recently new drugs were developed like valaciclovir and famciclovir that show superior efficacy and good safety and tolerability for patients.

Acyclovir with prednisone a complex of antiviral and steroids can be used to speed up the healing process, these drugs increase the likelihood of crusting and healing of lesions by about two-three times, when compared to placebo.

What medication is used to treat shingles pain?

Topical lidocaine and nerve blocks are used to control pain.

Precaution

How to take precautions from shingles?

Zostavax a live vaccine is available in the market since 2007, it is used as a precaution method.

How to prevent the spread of shingles?

1. Avoid touching the rash
2. Avoid scratching the rash or blisters, as the fluid within the blisters can be contagious
3. Cover the rash with cool wet cloths, or cool baths. Alternatively, Cool the rash with ice packs
4. Apply calamine lotion to the rash and blisters
5. Cover the rash with loose, non-sticky, sterile bandages
6. Avoid contact with pregnant women who have never had chickenpox until your rash crusted over

References

Verified by: Dr.Diab (December 18, 2017)

Citation: Dr.Diab. (December 18, 2017). What is Herpes Zoster? Causes Symptoms and Treatment. Medcoi Journal of Medicine, 7(2). urn:medcoi:article15576.