Varicella Infections in children ( Ref Nelson 19th Edition)

1. Dr. Avdhesh Agrawal
Registrar – Dr Atul’s Child Hospital
Varicella-Zoster Virus Infections

2.  Bushra SDPICU/ DR-6
 Yrs Female Child
 Fever
 Rash
 Malaise
 Anorexia
 Headache
 Rash- Intense Pruritic
 Difficulty in Standing
 Abnormal Gait
 Sick Look

6. Noted Points
 History of Contact
 Distribution of Rashes
 Crops of Rashes in various phases
 Systemic Symptoms subsided in 3-4 days

7. About the culprit Agent
 Virus
 NEUROTROPIC
 human herpesvirus- Alpha Herpes Virus
 virus is enveloped with double-stranded DNA
genomes
 encode more than 70 proteins

8. What does it do....?
 Varicella-zoster virus (VZV) causes primary, latent,
and recurrent infections.
 The primary infection is manifested as varicella
(chickenpox)
 Recurrent infection known as Herpes zoster / Shingles

9. Interesting Data
 USA –
 Annual Case – 40 Lakh ,
 Hospitalizations – 11000-15000
 Deaths- 100-150
 Primary Varicella – Mortality Rate- 2-3/ 100000 cases
 Lowest among 1-9 yrs of age
 Infants – 4 times risk
 Adults – 25 times risk of dying
 Mortality rate is 7-14% in untreated primary infection in immunocompromised
children
 50 % in untreated adults with pneumonia
 transmission of VZV to susceptible individuals occurs at a rate of 65-86%
 contagious 24-48 hr before the rash is evident and until vesicles are crusted
 2 Days before to 7 days/ crusting

10. Contagiousness
1-2 days
all lesions
are crusted
5 days

11. Pathogenesis
 VZV is transmitted in
 by airborne spread - oropharyngeal secretion
 through direct contact - fluid of skin lesions

12. Pathogenesis......Contd

13.  Virus is transported in a retrograde manner through
sensory axons
dorsal root ganglia throughout the spinal cord
virus establishes latent infection in the neurons and satellite
cells
Subsequent reactivation of latent virus
herpes zoster

14. Clinical Manifestation
 Varicella (Chicken pox)
 Varicella Zoster/ Herpes Zoster
 Breakthrough varicella
 Progressive varicella
 Neonatal varicella
 Congenital varicella syndrome

15. Varicella (Chickenpox)
 Acute Febrile Rash
 incubation period is 10 -21 days.
 Subclinical varicella is rare
 Prodromal symptoms
 Fever
 malaise
 anorexia
 headache
 mild abdominal pain
 Systemic Symptoms resolves within 2-4 days after onset of
rash

17.  Varicella lesions
 appear first on the scalp, face, or trunk.
 Centripetal Distribution
 The initial exanthem consists of intensely pruritic
 erythematous macules
 papular stage
 fluid-filled vesicles.
 Clouding and umbilication of the lesions begin in 24-48 hr.

18. • simultaneous presence of lesions in various
stages of evolution is characteristic of varicella
• The number of varicella lesions 10 to 1,500
• Ulcerative lesions involving the mucosa of
oropharynx and vagina

19.  vesicular lesions on the eyelids and
conjunctivae and mucosa
 The exanthem may be much more
extensive in children with skin disorders
 Hypopigmentation or hyperpigmentation
of lesion sites persists for days to weeks.
 No Scarring or marks

23. differential diagnosis
 vesicular rashes caused by other infectious agents :-
 enterovirus
 monkey pox
 rickettsial pox
 S. aureus
 drug reactions
 disseminated herpes zoster
 contact dermatitis
 insect bites
 Small Pox

24. Herpes zoster
 reactivation of latent VZV.
 uncommon in childhood
 Zoster is not caused by exposure to a patient with varicella
 The lifetime risk for herpes zoster for individuals with a
history of varicella is 10-20%
 75% of cases occurring after 45 yr of age.
 Herpes zoster is very rare in healthy children <10 yr of
age
 2nd episode of HZ 4%
 3 or more episodes are rare
 Is Herpes Zoster Infectious ......???

25. vesicular rash that usually is dermatomal in
distribution.
necrotic changes may be produced in the
associated ganglia.
The skin lesions of varicella and herpes
zoster have identical histopathology
infectious VZV is present in both.

26.  manifests as vesicular lesions clustered within 1 or 2
adjacent dermatomes
 rash is mild, with new lesions appearing for a few days
 Herpes zoster in children tends to be milder than
disease in adults
 It occurs more frequently & disease is more severe if-
 Children is on immunosuppressive therapy
 HIV infected children.
 postherpetic neuralgia is very unusual in children.
 Transverse myelitis with transient paralysis is a rare
complication of herpes zoster

27. Herpes zoster involving the lumbar dermatome.

29. Varicella in Vaccinated Individuals
(“Breakthrough Varicella”)
 One dose of varicella vaccine is >97% effective in
preventing severe varicella
 85% effective in preventing all disease after exposure
to wild-type VZV.
 Breakthrough disease is varicella that occurs in a
person vaccinated >42 days before rash onset and is
caused by wild-type VZV

30.  rash occurring < 14 days after vaccination was most
commonly wild-type VZV
 Rash occurring 14-42 days after vaccination was due
to either
 Wild-type VZV-------- breakthrough varicella
 vaccine strains---------vaccine-associated rash
 ????????

31.  The Breakthrough varicella rashes are
 atypical
 predominantly maculopapular
 vesicles are seen less commonly
 illness is most commonly mild with <50 lesions
 shorter duration of rash
 Less contagious
 Complications are less
 little or no fever

33. Progressive Varicella
 Progressive varicella, is a severe complication of
primary VZV infection.
 visceral organ involvement
 coagulopathy
 severe hemorrhage
 Continued new vesicular lesion development
 Severe abdominal pain

34.  appearance of hemorrhagic vesicles
 the risk for progressive varicella
 congenital cellular immune deficiency disorders
 Malignancy
 organ transplantation
 Pt. is on steroid therapy
 Unusual clinical findings
 develop a unique hyperkeratotic appearance
 continued new lesion formation for weeks or months

35. Neonatal Varicella
Infants whose mothers demonstrate varicella in the period
from 5 days prior to delivery to 2 days afterward are at
high risk for severe varicella.
 The infant acquires the infection transplacentally
 The infant's rash usually occurs toward the end of the 1st
week to the early part of the 2nd week of life
 maternal immunoglobulin G (IgG) is able to cross the
placenta if delivery occurs after 30 wk of gestation
 ?????

37.  Newborns whose mothers demonstrate varicella 5 days
before to 2 days after delivery should receive 1 vial of
VariZIG as soon as possible.
 All premature infants born <28 wk gestation to a mother
with active varicella at delivery (even if the maternal rash
has been present for >1 wk) should receive VariZIG
 intravenous immune globulin (IGIV) may provide some
protection
 the infant should be treated with acyclovir (10 mg/kg every
8 hr IV) when lesions develop.
 prognosis is good if pt. receive prompt antiviral therapy


38. Congenital Varicella Syndrome
 In Utero Transmission
 Risk of infection (No disease)
 Early part of pregnency- 25%
 Risk of CVS ( Disease)
 Before 13 wks of gestation – 0.4%
 In between 13 – 20 wks - 2%

39. CVS Manifestations
Organ/ System Manifestations
Skin Cicatricial skin scarring
LIMB Limb hypoplasia
NEUROLOGIC Microcephaly, cortical atrophy, seizures, and mental
retardation
EYE Chorioretinitis, microphthalmia, and cataracts
RENAL Hydroureter and hydronephrosis
ANS Neurogenic bladder, swallowing dysfunction, and
aspiration pneumonia

44. Diagnosis of CVS Fetopathy
 The diagnosis of VZV fetopathy is based mainly on the
 history of gestational varicella
 presence of characteristic abnormalities in the newborn
infant
 viral DNA may be detected in tissue samples by PCR.
 VZV-specific IgM antibody is detectable in the cord
blood
 Chorionic villous sampling

45. Diagnosis of varicella
 Laboratory evaluation has not been considered
necessary
 Leukopenia
 relative and absolute lymphocytosis.
 liver function tests are mildly elevated
 CSF in CNS complications
 mild lymphocytic pleocytosis
 moderate increase in protein content

46.  Rapid laboratory diagnosis
 direct fluorescence assay
 rapid culture with specific immunofluorescence staining
 PCR amplification testing
 multinucleated giant cells can be detected with
nonspecific stains Tzanck smear
 VZV IgG antibodies:- Rise > 4 fold ???
 Testing for VZV IgM antibodies is not useful

47. Treatment in Varicella
Acyclovir therapy is
Not Recommended Routinely
for treatment of
uncomplicated varicella in the otherwise
healthy child
the marginal benefit
the cost of the drug
low risk for complications of varicella.

48. Oral Acyclovir Theraphy
 Oral acyclovir in
 children >12 mo of age with
 chronic cutaneous or pulmonary disorders
 Pt. Is on corticosteroid therapy
 individuals receiving long-term salicylate therapy
 Possibly Secondary cases among household contacts ??
 Nonpregnant individuals > 13 years of age
 Dose – 20mg/Kg/ Dose QID for 5 days
 Within 24 Hours of onset of exenthem

49. Intravenous Acyclovir therapy
 Varicella with severe disease/ complicated cases
 pneumonia
 severe hepatitis
 thrombocytopenia
 encephalitis
 varicella in immunocompromised patients
 Dose:- IV acyclovir (10 mg/Kg/ Dose or 500 mg/m2 every 8 hr
IV) continued for 7–10 days
 To be given even after > 72 Hours of Rash onset
 Other molecules
 famciclovir
 Valacyclovir
 Acyclovir-resistant VZV:- intravenous foscarnet
( 120 mg/kg/day TDS for upto 3 Wks)

50. Treatment in Herpes Zoster
 uncomplicated HZ in children - antiviral agent may not always be necessary
 herpes zoster in immunocompromised
 Acyclovir (500 mg/m2 or 10 mg/kg every 8 hr IV).
Adults-
 Acyclovir 800 mg 5 times a day for 5 days
 Famciclovir 500 mg TDS for 7 days
 Valacyclovir 1000 mg TDS for 7 days
 Use of corticosteroids in the treatment of herpes zoster in children is not
recommended but can be given in elderly to improve quality of life.

51. Complications
 more common in immunocompromised patients
 In healthy child, mild varicella hepatitis is relatively
common
 Mild thrombocytopenia occurs in 1-2%
 Other Complications
 Bacterial Infections
 Encephalitis and Cerebellar Ataxia
 Pneumonia
 Nephritis and Nephrotic Syndrome
 HUS
 Arthritis
 Mycocarditis
 Pericarditiis
 Pancreatitis and Orchitis

52. Bacterial Infections
 Secondary bacterial infections of the skin
 group A streptococci and S. aureus
 occur in up to 5% of children
 impetigo
 cellulitis
 lymphadenitis
 subcutaneous abscesses.
 manifestation of secondary bacterial infection
 erythema of the base of a new vesicle.
 Recrudescence of fever 3-4 days after the initial exanthem

53.  Other invasive complications
 varicella gangrenosa
 bacterial sepsis
 pneumonia
 arthritis
 osteomyelitis
 cellulitis
 necrotizing fasciitis
 toxic shock syndrome

54. Encephalitis and Cerebellar Ataxia
 morbidity from CNS complications is highest among
patients < 5 yr
 Nuchal rigidity
 altered consciousness
 seizures
 gait disturbance
 nystagmus, and slurred speech
 Neurologic symptoms usually begin 2-6 days after the
onset of the rash.
 Clinical recovery is rapid and is usually complete in
24-72 hrs

55. Pneumonia
 Respiratory symptoms, which may include
 cough
 dyspnea
 cyanosis
 pleuritic chest pain
 hemoptysis

56. EVIDENCE OF IMMUNITY TO
VARICELLA
Evidence of immunity to varicella consists of any of the
following:
Documentation of age-appropriate vaccination with a
varicella vaccine:
• Preschool-aged children (i.e., aged >12 mo): 1 dose
• School-aged children, adolescents, and adults: 2 doses
Lab evidence of immunity or laboratory confirmation of
disease
Diagnosis or verification of a history of varicella disease/
herpes zoster by a health-care provider

57. Post exposure Prophylaxis
Vaccine:- given to healthy children within 3-5 days after exposure (
ASAP)
High-titer anti-VZV immune globulin is recommended
- immunocompromised children
- pregnant women without evidence of immunity
- newborns exposed to varicella
- Close contact b/w susceptible high risk patient and patient of HZ
- 1 vial / 125 Units .....per 10 Kg
- Max 625 Units
New Borns :
 < 28 wks gestation, exposed to varicella, regardless of maternal
immunity
 >28 wks gestation, exposed to varicella, no evidence of maternal
immunity
Adults – IG G titre to be done before anti VZV IG

58. Take Home Msgs
 Identification of Disease
 Laboratory Investigations
 Treatment and Supportive t/t
 Early identification of complications and management
 Post exposure prophylaxis counselling
 Syp Acyclovir 400mg/ 5ml , Zovirex 200 Rs
 Tab Acyclovir 200 400 600 800 (146/ 5 Tab)
 Inj Acyclovir , 250 mg , 246 Rs
 Vaccine Rs 1700

59. Thanks….