Transcript Document

Chickenpox
(Varicella)
Ana Corona, FNP
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What is Chickenpox (Varicella)?
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Chickenpox is an acute
viral infectious disease
Varicella-zoster virus
(VZV)
VZV is a DNA virus
A member of Herpes virus
group.
Primary infection results
in Varicella.
Recurrent infection results
in herpes zoster (shingles).
Pathogenesis of Varicella
Day 0 – 3
•Infection of conjunctivae and/or
mucosa of the upper respiratory tract
•Viral replication in regional lymph
nodes
Day 4 – 6
•Primary Viremia
•Viral replication in liver, spleen,
and other organs
Days 10 – 12
•Secondary Viremia
Day 14
•Infection of skin and appearance of
vesicular rash
Clinical Features
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Mild prodrome (fever,
malaise) for 1-2 days
Successive crops (2-4 days)
of pruritic vesicles
Generally appear first on
head; most concentrated
on trunk
Can spread over the entire
body causing between 250
to 500 itchy blisters
Generally mild in healthy
children
What is The Chickenpox Illness
Like?
• Chickenpox most commonly causes an illness that
lasts about 5-10 days.
• Children usually miss 5 or 6 days of school or
childcare due to chickenpox.
• 1 child in 10 has a complication from chickenpox
serious enough to visit a health care provider
• Including infected skin lesions and other infections.
• Dehydration from vomiting or diarrhea
• Exacerbation of asthma
• More serious complications such as pneumonia
The Lesions
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Each lesion progresses through
a series of characteristic stages
over about a week.
Papules and vesicles develop
into pustules, which then crust
over prior to healing.
A prominent feature of
chickenpox is the development
of several crops of spots.
The peak of the illness, 3-4 days
after first appearance of the
rash, there are lesions at all
stages of development, from
new vesicles through to crusts.
Transmission: How do you get
Chickenpox?
• Acquired by inhaling virus-containing particles,
trapped in tiny droplets released into the air from
the nose or throat of an infected person.
• The virus (VZV) enters the body by infecting cells in
the respiratory tract.
• It spreads to many other parts of the body, including
the skin, where it causes the characteristic rash.
• A person with chickenpox is contagious 1-2 days
before the rash appears and until all blisters have
formed scabs.
• It takes from 10-21 days after contact with an
infected person for someone to develop chickenpox
Incubation period and prodromal
illness
• The wide range commonly quoted for the incubation
period: 7-23 days.
• Time of contact and true source of infection may be
difficult to pinpoint.
• General constitutional symptoms sometimes
precede the rash.This is called a prodrome.
• Young children generally have either no or a very
mild prodrome.
• Older children and adults: the prodrome may be
more pronounced.
• Symptoms include fever (which may precede the
rash by up to 6 days), headache, backache and sore
throat
The Stages of Chickenpox
Incubation Period
Usually (14-17 days)
Prodrome (1 – 3 days)
Vesicles
Pustules
Scabs
Recovery typically 7 days after
rash appears (ranges 5 - 35 days)
Herpes Zoster (Shingles)
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Reactivation of Varicella
Zoster Virus
Associated with:
– Aging
– Immunosuppression
– Intrauterine
exposure
– Varicella at <18
month of age
Can chickenpox be caught from
someone with Herpes Zoster
(Shingles)?
• Yes.
• The rash of shingles contains VZV particles, just like
the rash of chickenpox.
• Shingles carries a small risk of transmitting
chickenpox to someone who has not had
chickenpox before.
• An infant might acquire chickenpox by very close
contact with a grandparent with shingles
• The risk of transmission is low - because VZV is not
excreted from the throat during shingles.
Complications
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Bacterial infection of lesions
CNS manifestations
Pneumonia (rare in children)
Hospitalization: 3 per 1000 cases
Death: 1 per 60,000 cases
Groups at Increased Risk of
Complications
• Normal Adults
• Immunocompromised persons
• Newborns with maternal rash onset within
5 days before to 48 hours after delivery
Chickenpox during pregnancy may
result in:
• Congenital Varicella syndrome
• Severe Varicella syndrome
• Risk of neonatal death
Congenital Varicella Syndrome
• Results from maternal infection during
pregnancy
• Period of risk may extend through first 20
weeks of pregnancy
• Atrophy of extremity with skin scarring, low
birth weight, eye and neurologic
abnormalities
• Risk appears to be small (<2%)
Laboratory Diagnosis
• Laboratory diagnosis is not routinely required
• Useful if confirmation of the diagnosis or
determination of susceptibility is necessary
• Most frequent source of isolation is vesicular fluid
• Stained smears from vesicular scrapings (Tzanck
Smear).
• Serology Tests for Varicella IgM antibody
• ELISA and Latex Agglutination (LA) useful in
screening for varicella immunity
Can you get chickenpox more
than once?
• Yes
• But it is uncommon to do so.
• For most people, one infection is thought to
confer lifelong immunity.
Management
• Interventions designed to minimize fever and
discomfort:
• Antipyretic medicines
• Cool baths and soothing lotions
• Chickenpox is not usually treated with a specific
antiviral compound owing to its short duration and
generally mild, uncomplicated nature.
• Antiviral medication may be appropriate for older
patients, in whom the disease tends to be more
severe.
Acyclovir Therapy
• Healthy nonpregnant persons >13 years of age
• Children >12 months with chronic cutaneous or
pulmonary disorders or on salicylate therapy
• Children receiving short intermittent or
aerosolized steroids
• IV in Immunocompromised children and adults
with viral-mediated complications
• Not recommended for post-exposure prophylaxis
What home treatments are
available for chickenpox?
• Fingernails trimmed short
• Calamine lotion and Aveeno (oatmeal) baths may
help relieve some of the itching
• Aspirin or aspirin-containing products to relieve
your child's fever are not recommended.
• The use of aspirin has been associated with
development of Reye syndrome (a severe disease
affecting all organs - most seriously affecting the
liver and brain, that may cause death).
• The use of non aspirin medications such as
acetaminophen is recommended.
Complications
• Certain groups of persons are more likely
to have more serious illness with
complications.
• These include adults, infants, adolescents
and people with weak immune systems
from either illnesses or from medications
such a long-term steroids.
What Complications Result
From Varicella?
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The most common
complications are:
Bacterial infections of
the skin and soft
tissues in children
Septicemia
Toxic Shock
Syndrome
Necrotizing Fascitis
Osteomyelitis
Bacterial pneumonia
Septic arthritis.
Complications: Continued
• Varicella is a well described risk factor for
invasive group A streptococcus infections.
• Other complications:
• Cerebellar ataxia
• Encephalitis
• Hemorrhagic complications leading to
bleeding disorders including disseminated
intravascular coagulation (DIC).
Morbidity and mortality
• Since 1999, states have been encouraged to
report chickenpox deaths to CDC.
• In 1999 and 2000, CDC received reports
that showed that deaths from chickenpox
continue to occur in healthy, unvaccinated
children and adults.
• Most of the healthy adults who died from
chickenpox contracted the disease from
their unvaccinated children.
How serious a disease is
varicella?
• Prior to the availability of varicella vaccine
there were approximately 4 million cases of
varicella a year in the U.S.
• Many health care providers are not aware
that 11,000 hospitalizations and 100 deaths
occurred every year in the United States
before varicella vaccine became available.
• The majority of deaths and complications
occurred in previously healthy individuals.
When is it necessary to go to the
doctor for treatment?
• If a fever lasts longer than 4 days or rises above 102
ºF.
• Lesions which become very red, warm, tender, or is
leaking pus may mean there is a bacterial infection.
• Lethargy
• Difficulty walking
• Stiff neck
• Severe Vomiting
• Difficulty breathing
• Severe cough.
Can chickenpox be prevented?
 Yes, chickenpox can
now be prevented by
vaccination
Varicella Vaccine
Composition
Efficacy
Live Virus (Oka-Merck
strain)
95% (range 65%-100%)
Duration of Immunity
>7 years
Schedule
1 dose (<13 years of age)
Varicella Vaccine Recommendations
• Routine vaccination at 12 to 18 months of
age
• Recommended for all susceptible children
by the 13th birthday
• Persons >13 years of age without history of
Varicella
• Two doses separated by 4 – 8 weeks
Varicella Vaccine: Post-exposure
Prophylaxis
• Varicella vaccine is recommended for use in
susceptible person after exposure to
Varicella
• 70% - 100% effective if given within 72 hours
of exposure
• Not effective if >5 days but will produce
immunity if not infected
Varicella Vaccine: Adverse Reactions
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Injection site complaints: 20%
Rash: 3% - 4%
May be maculopapular rather than vesicular
Average 5 lesions
Systemic reactions uncommon
Zoster Following Vaccination
• Most cases in children
• Risk from wild virus 4 to 5 times higher
than from vaccine virus
• Mild illness without complications
Varicella Vaccine: Contraindications
and Precautions
• Severe allergy to vaccine component or
prior dose of vaccine
• Pregnancy
• Immunosuppression
• Moderate or severe acute illness
• Recent blood product
• Immunocompromised persons should not
be vaccinated
• Vaccinate persons with humoral
immunodeficiency
Varicella Zoster Immune Globulin
(VZIG)
• May modify or prevent disease if given <96 hours
after exposure
• Indications:
– Immunocompromised persons
– Newborn of mothers with onset 5 days before to
2 days after birth
– Premature infants with postnatal exposure
– Susceptible adults and pregnant women
What problems can occur after
chickenpox vaccination?
• Soreness, redness, or swelling at injection site is the
most common side effect, occurring about 20% of
the time.
• A very mild rash or several small bumps can result
in about 1% to 4% of vaccine recipients.
• It may be possible for someone who gets a rash
from chickenpox vaccine to give vaccine strain
chickenpox to another person.
• The vaccine may cause a mild fever 2 weeks after
vaccination.
• Seizures usually caused by fever may occur in less
than 1 in 1000 vaccine recipients.
Have serious reactions ever
occurred from the chickenpox
vaccine?
• After distribution of the first 10 million
doses of the vaccine, reports of serious
adverse events after vaccination
• Seizures, encephalitis, pneumonia, ataxia
and anaphylaxis have been very rare,
occurring approximately 1 for every 50,000
doses given
What should I do if there is a
serious reaction after chickenpox
vaccination?
• Call health care provider or 911 right away.
• Write down what happened and the date
and time it happened.
• Ask your health care provider or health
department to file a Vaccine Adverse Event
Report Form or you can call (800) 822-7967
(toll-free).
Vaccine Birth Defects
• There is a theoretical risk that when
administered one month prior to, or during,
pregnancy, the vaccine may cause birth
defects similar to those that can occur from
natural chickenpox:
• Limb abnormalities
• Abnormal brain development
• Mental Retardation
• Scarring of the skin and eye abnormalities
Why not allow children to acquire natural infection
and offer vaccine only to susceptible adolescents
and adults?
• Approximately 60% of hospitalizations and
40% of deaths due to varicella occur in
children less than 10 years of age.
• The majority of this morbidity is
preventable by vaccination.
Continued
• Children miss an average of 5-6 days of
school when they have varicella
• Caregivers miss 3-4 days of work to care for
their sick children.
• The majority of adults who acquire varicella
and persons at high risk for severe disease
who are not eligible for vaccination,
contract the disease from unvaccinated
children.
Evaluation of Patient Education
Materials
Usefulness
Provide useful
information
Prevention
Readability
Easy to read 5th – 6th
grade reading level
Availability
Easy access from medical
office, DHS
Cost
Free
No cost
Evaluation of Community Resources
Services offered
Information on preventive
measures
Immunizations
Population served
Unimmunized population
against chickenpox
Accessibility of services
Immunization Clinics
Easy access
Payment for services
Free Immunizations
Community Resources
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Keepkidshealthy.com:
http://visit.referralware.com/2/FreeOffer.jsp
Information on Shingles: CDC:
http://www.cdc.gov/nip/diseases/varicella/faqs-gen-shingles.htm
Varicella Vaccination in Pregnancy Registry: 1 (800) 986-8999
Varicella Vaccine Information: 1 (800) 9VARIVAX
Information on acyclovir therapy
http://www.aap.org/family/chckpox.htm
Prevention of Varicella: Updated Recommendations of the Advisory
Committee on Immunization Practices (ACIP)
http://www.cdc.gov/epo/mmwr/preview/mmwrhtml/rr4806a1.htm
Immunization Action Coalition: www.immunize.org
Merck: www.chickenpoxinfo.com
National Immunization Program website: http://www.cdc.gov/nip
Vaccine Adverse Event Report (800) 822-7967
Los Angeles County Department of Health Services Clinics: 313 N.
Figueroa St. Los Angeles, CA 90012: [email protected]
Question
1. A 6-year-old boy receiving prednisolone 2 mg/kg
for asthma comes to the clinic the day he develops
varicella rash. Which of the following is the
required treatment?
A:Varicella-zoster immune globulin (VZIG)
B: Acyclovir
C:Varicella vaccine
D: All of the above
E: None of the above
Answer
The correct answer is B:
• VZIG and vaccine are effective if given
within 3-4 days of exposure but are
ineffective once the varicella rash has
appeared.
• Children on systemic steroids are at high
risk for complications and should receive
acyclovir
Quiz: True or False?
2. Varicella spread can be prevented by
isolating all children with Varicella rash.
ANSWER
• False: The disease is infectious 2 days
before the rash appears.
• Children also may acquire the disease
from adults with herpes zoster
References
1. Atkinson, W. Wolfe, C. & Humiston, S. (2000).
Epidemiology and prevention of vaccinepreventable diseases (6th ed.). Centers for Disease
Control and Prevention.
2. Centers for Disease Control and Prevention:
http://www.cdc.gov
3. Immunization Action Coalition:
www.immunize.org
4. Merck, (1999). Chickenpox: A disease worth
preventing. Merck & Co., Inc.
5. Varicella from Pediatrics:
http://author.emedicine.com/PED/topic2385.htm
Any Questions?