Dec 24, 2008

Chicken Pox

Chickenpox
(Varicella)
Definition
Chickenpox is a highly contagious viral infection. It produces a widespread itchy rash. Chickenpox can cause serious complications when contracted by adults, newborns, or people with suppressed immune systems.
Chickenpox

Causes
Chickenpox is caused by the varicella zoster virus (VZV). It spreads from person to person via:
• Airborne droplets of moisture containing the VZV virus
• Direct contact with fluid from a chickenpox rash
Chickenpox is contagious 1-2 days before the rash erupts. However, it is most contagious just after the rash has broken out. It remains contagious until all of the blisters have crusted.
Risk Factors
A risk factor is something that increases your chance of getting a disease or condition.
Risk factors include:
• Close contact with an infected person (unless you've been vaccinated against or have already had chickenpox)
• Age: less than three years old with peak incidence between 5-9 years old
• Immune deficient state (leukemia, transplantation)
• Time of year (late winter, early spring)
Symptoms
Adults have more severe symptoms than children. Symptoms usually break out 10-21 days after contact.
Initial symptoms include:
1. Mild headache
2. Moderate fever
3. General feeling of malaise
Within 1-2 days after the initial symptoms, a rash develops. The rash consists of small, flat, red spots. The spots become raised and form a round, itchy, fluid-filled blister. The blisters develop in clusters, with new clusters forming over 5-6 days.
The rash usually develops on the skin above the waist, including the scalp. The rash may also appear on the eyelids, in the mouth, upper airway, voice box, or on the genitals. The rash typically crusts over by day six or seven and disappears within three weeks.
Diagnosis
The doctor will ask about your symptoms and medical history, and perform a physical exam. Diagnosis is usually made on the basis of age and the rash. Blood and laboratory tests to identify the VZV virus are rarely necessary.
Treatment
In most people, chickenpox is mild and will naturally run its course. In these cases, treatment focuses on relieving the symptoms.
To Reduce Itching
• Wet compresses on the skin
• Nonprescription anti-itch creams or lotions
• Oatmeal baths
• Oral antihistamines
Note: Aspirin should not be given to children, adolescents, and young adults with chickenpox because of the increased risk of Reye's syndrome.
Antibiotics
Since a virus causes chickenpox, antibiotics are not curative. They may be prescribed, however, if the rash becomes infected with bacteria.
Antiviral Medication
There are several antiviral drugs (acyclovir, valacyclovir, famciclovir) which may shorten the course and reduce the severity of infection. They are often used in:
• Adolescents and adults as well as those individuals with compromised immune systems. Moreover, these drugs are used in those individuals with chronic skin or lung diseases and those on aspirin or steroids.
Special Needs
Varicella-zoster immune globulin is often given immediately after exposure to VZV to newborns and people with compromised immune systems.
Prevention
If you have not had chickenpox and have never been vaccinated, avoid contact with anyone who has it.
Several US government agencies and medical groups recommend that all children be routinely vaccinated with an active varicella vaccine at 12-18 months of age and that all susceptible children receive the vaccine before their 13th birthday. Older children and adults should receive two vaccines 4-8 weeks apart if they are not known to have had chickenpox in the past.