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CHICKENPOX (VARICELLA) Sarah Fisher

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Page 1: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

CHICKENPOX (VARICELLA)Sarah Fisher

Page 2: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

What is Chickenpox?

• Highly contagious disease caused by Varicella Zoster Virus (VZV)

• On of the most commonly contracted childhood diseases

• Usually mild and not life-threatening to otherwise healthy patients• Potentially severe in infants, adults

and others with impaired immune systems

• Infections cause long-term immunity—second infections are rare

Page 3: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

History

• 1500s: Believed to have been first discovered by Giovanni Fillipo in Italy

• 1600s: English physician Richard Morton gave the disease the name “chickenpox” because he believed it was a milder version of smallpox

• 1700s: English physician William Heberden became the first physician to prove that chickenpox and smallpox were two different diseases

Page 4: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

History Cont. • 1888: Relationship between Herpes Zoster and

chickenpox was suggested• 1986: Complete DNA sequence of VZV was established• 1995: FDA approved vaccine to immunize children and

other susceptible individuals against chickenpox

Page 5: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Transmission• One of the most readily transmissible diseases• Can be spread from person to person by:

• Direct contact with fluid from the blisters• Direct contact with secretions from the respiratory tract• Handling an infected person’s clothing or bedding• Exposure to the coughing or sneezing of an infected person

(airborne)• Touching or breathing in the virus particles that come from

chickenpox blisters

• Susceptibility is universal among those not previously infected

• Greatest number of cases occur in the winter/early spring

Page 6: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Symptoms

• Symptoms usually start about two weeks after exposure • Fever, tiredness, loss of appetite, headache, an itchy rash• Rash generally starts as little red spots on the chest,

stomach or back and then spreads to the face • Infected patient may only get a few spots, a large cluster or

develop hundreds of spots during the first 3-5 days of the rash• Spots turn into clear, fluid-filled blisters and eventually turn to scabs

(2-4 days)

• Very contagious 1-2 days before rash appears and until all blisters have formed scabs

Page 7: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Complications • Not common in otherwise healthy people• People with more severe risks for complications:

• Infants• Adolescents• Adults• Pregnant women• People with weakened immune systems because of illness or

medications

• 1/400 patients need hospitalization • Approx. 90 deaths/year

Page 8: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Complications Cont. • Serious complications include:

• Dehydration• Pneumonia• Bleeding problems• Brain infection/inflammation• Bacterial infects of the skin/soft tissues• Blood stream infections (Sepsis)• Toxic shock syndrome• Bone infections• Joint infections

• Chickenpox remains latent and may recur years later as Herpes Zoster (shingles)• Risk increases with age and for those with HIV

Page 9: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Prevention

• The best way to prevent the disease is to get vaccinated—98% percent effective• Children, adolescents and

adults should have two doses• With the vaccine, it is still

possible to contract the disease but it will be much more mild with fewer blisters and a mild or no fever

• Vaccine is required for attendance in day care and schools

Page 10: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Prevention Cont.• If you have never had chickenpox, vaccinated or not, you

should stay away from any infected people • Some newborn babies, any immune-deficient child and

any susceptible persons over 14 years of age who have not been previously vaccinated may need a shot of varicella zoster immune globulin (VZIG) to try and prevent chickenpox contraction after exposure

Page 11: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Treatment• Acetaminophen can be given to reduce fever

• Aspirin should not be given because it may cause Reye syndrome

• Calamine lotion, antihistamines and oatmeal baths can be given to help reduce itching

• Acyclovir is a new drug now given to some patients within the first day after rash onset to make the symptoms milder

Page 12: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Epidemiology• Varicella is endemic in the US with seasonal fluctuation• Between 150,000-200,000 cases are reported annually to

the CDC (1998)• Highest attack rates are in children ages 509—60% of all

cases

Page 13: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Epidemiology Cont. • By adulthood, 90-95% of the US population have

antibodies to varicella • In the tropics, varicella occurs more often in adults so

immigrants from these areas are more likely to be susceptible than the rest of the population at comparable ages

Page 14: CHICKENPOX (VARICELLA) Sarah Fisher. What is Chickenpox? Highly contagious disease caused by Varicella Zoster Virus (VZV) On of the most commonly contracted

Herpes Zoster (Shingles)• Reactivation of latent varicella zoster virus (VZV)• Associated with aging, immunosuppression, in-utero

exposure to varicella, and postnatal varicella (before 18 months)

• In the immunocompromised, zoster can disseminate, causing generalized skin lesions, and central nervous system (CNS), pulmonary, and hepatic involvement