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What is Varicella (Chickenpox)?

  • Chances are, you have had varicella (chickenpox) as a child. Varicella is a DNA virus and a member of the herpervirus group, occurring in individuals most often in the winter and early spring.
  • Primary infection results in chickenpox and recurrent infection thereafter occurs as herpes zoster (shingles).
  • Those who contact the varicella virus have lifelong immunity.
  • The primary site of infection is through the respiratory tract from airborne droplets or direct contact with the lesion.
  • Chickenpox is contagious 1-2 days before to 4-5 days after onset of rash or until lesions have formed crusts. [1]

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Varicella Symptoms

  • A rash is generally the first sign of chickenpox in children, and in teenagers or adults the first sign may be a mild fever, occuring 14-16 days (range 10-21 days) after coming into contact with the virus.
  • The pruritic (itchy) rash generally appears first on the head and then most concentrated on the trunk.
  • New crops of the rash will appear and there will be different stages of the rash present on the body.
  • Lesions also can occur on mucous membranes of the oropharynx, respiratory tract, vagina, conjunctiva, and the cornea.
  • Lesions are usually 1 to 4 mm in diameter.
  • The vesicles are superficial and delicate and contain clear fluid on an erythematous base.
  • Vesicles may rupture or become purulent before they dry and crust. [1]


  • fatigue/malaise
  • pruritis (itching)
  • low grade fever, 102F (2-3 days)


  • Adults may suffer more severely regarding the symptoms above.


  • Children with lymphoma and leukemia may develop a severe progressive form of varicella characterized by high fever, extensive vesicular eruption, and high complication rates.
  • Children infected with human immunodeficiency virus also may have severe, prolonged illness.


  • Secondary bacterial infection of skin lesions by resistant staph.
  • Pneumonia (bacterial/viral)
  • Encephalitis: 1.8 per 10,000 cases
  • Reye’s Syndrome (when parents administer aspirin to young children during acute phase of disease)
  • Hospitalizations: 2-3 per 1,000
  • Death: 1 per 60,000 cases (ages 1-14: 1 per 100,000 cases, ages 15-19: 2.7 per 100,000 cases, ages 30-49: 25.2 per 100,000 cases)

Groups at Increased Risk for Varicella Complications:

  • Persons older than 15 yrs
  • Infants younger than 1 yr
  • Immunocompromised
  • Newborns of women with rash onset within 5 days before to 2 days after delivery

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Conventional Treatment for Varicella

  • There is no specific medical treatment and the virus must run its course, generally 100% lifelong immunity thereafter.
  • Administering valacyclovir within 24-48 hours of onset of rash may lessen the symptoms of chickenpox.

In those individuals who have not received the varicella vaccine, VariZIG™ may be used to lessen the symptoms of those individuals who have been exposed:

  • Immunocompromised patients.
  • Neonates whose mothers have signs and symptoms of varicella around the time of delivery (i.e., 5 days before to 2 days after).
  • Premature infants born at >28 weeks of gestation who are exposed during the neonatal period and whose mothers do not have evidence of immunity.
  • Premature infants born at <28 weeks of gestation or who weigh <1,000 g at birth and were exposed during the neonatal period, regardless of maternal history of varicella disease or vaccination.
  • Pregnant women.
  • FDA information on VariZIG™
  • CDC Investigational Information – VariZIG™

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When is the Varicella Vaccine Given?

 12 months, 5 years

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Efficacy of the Varicella Vaccine

One dose

  • 1 dose of single-antigen varicella vaccine is—
    • 85% effective at preventing any form of varicella
    • almost 100% effective against severe varicella [11]

Two doses

  • In a pre-licensure clinical trial, 2 doses of vaccine were—
    • 98% effective at preventing any form of varicella
    • 100% effective against severe varicella
  • In post-licensure studies, 2 doses of vaccine were—
    • 88% to 98% effective at preventing all varicella [11]

In Children with HIV-infection

  • 1 dose of single-antigen varicella vaccine is—
    • 82% effective at preventing any form of varicella

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How Long Does Varicella Vaccine Protection Last?

It is not known how long a vaccinated person is protected against varicella. But, live vaccines in general provide long-lasting immunity. [11]

  • Several studies have shown that people vaccinated against varicella had antibodies for at least 10 to 20 years after vaccination. But, these studies were done before the vaccine was widely used and when infection with wild-type varicella was still very common.
  • A case-control study conducted from 1997 to 2003 showed that 1 dose of varicella vaccine was 97% effective in the first year after vaccination and 86% effective in the second year. From the second to eighth year after vaccination, the vaccine effectiveness remained stable at 81 to 86%. Most vaccinated children who developed varicella during the 8 years after vaccination had mild disease.[22]
  • A clinical trial showed that children with 2 doses of varicella vaccine were protected 10 years after being vaccinated. Fewer people had breakthrough varicella after 2 doses compared with 1 dose. The risk of breakthrough varicella did not increase over time.[23]

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Ingredients in the Varicella Vaccine

  • The live virus
  • Sucrose (sugar)
  • Saline solution
  • Gelatin MSG— 0.5 milligrams
  • Potassium
  • Residual components of the Merck human embryonic diploid cells, including DNA and proteins from the cells EDTA (a chemical used in a variety of products) in trace amounts
  • Neomycin (an antibiotic used to keep the cell cultures sterile) in trace amounts
  • Trace quantities of cow fetus serum

If you would like specific information regarding each ingredient, including studies: Vaccine Ingredients
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Varicella FDA Package Inserts

(Please read the “Contraindications/Warnings/Precautions/Adverse Reactions” VERY carefully inside each FDA Package Insert)


From FDA Package Insert for ProQuad:

Administration of ProQuad (dose 1) to children 12 to 23 months old who have not been previously vaccinated against measles, mumps, rubella, or varicella, nor had a history of the wild-type infections, is associated with higher rates of fever and febrile seizures at 5 to 12 days after vaccination when compared to children vaccinated with M-M-R® II and VARIVAX® (Varicella Only Vaccine) administered separately. [9] Back to Top

Controversy and the Varicella Vaccine

  • The varicella vaccine was studied on 10,000 children and 1,600 teens and adults for safety. [14-21]
  • VARIVAX Package Insert, PLEASE NOTE:

Risk of Vaccine Virus Transmission-

“Post-marketing experience suggests that transmission of vaccine virus may occur rarely between healthy vaccinees who develop a varicella-like rash and healthy susceptible contacts. Transmission of vaccine virus from a mother who did not develop a varicella-like rash to her newborn infant has been reported.  Due to the concern for transmission of vaccine virus, vaccine recipients should attempt to avoid whenever possible close association with susceptible high-risk individuals for up to six weeks following vaccination with VARIVAX.

Susceptible high-risk individuals include:

  1. Immunocompromised individuals
  2. Pregnant women without documented history of varicella or laboratory evidence of prior infection
  3. Newborn infants of mothers without documented history of varicella or laboratory evidence of prior infection and all newborn infants born at <28 weeks gestation regardless of maternal varicella immunity.
  •  DO NOT vaccinate your child(ren) with the chickenpox vaccine if you are PREGNANT or have a NEWBORN due to viral shedding!!!!
  • “[The vaccine] has not been evaluated for its carcinogenic or mutagenic potential, or its potential to impair fertility.” ~ (Varicella Vaccine Information Statement)
  • The death rate for those contracting varicella is 25 times higher in adults than in young children (25 per 100,000).  The duration of the vaccine lasts 10 years before having to be reinoculated, however acquiring the chickenpox virus naturally gives lifelong immunity.  Since the introduction of the vaccine, adults will now have to continue getting vaccinated all through life since the vaccine duration only lasts up to 10 yrs.  Chickenpox used to be a “childhood” illness, but unfortunately there may be a rise in adult chickenpox in the near future.

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Varicella Vaccine Reactions

Signs to look for include:

  • Injection site reactions occur in 20 percent of kids and one-third of teens and adults.
  • Fever is expected in 15 percent of people, and a mild chickenpox-like rash can occur in about 4 percent one to four weeks after the shot.
  • Systemic reactions, such as body aches, general ill feeling, irritability, fatigue, intestinal symptoms, or headache, occur in about 85 percent of people after the first dose and 66 percent after the second. [3,8]

Known Severe Reactions:

  • Pneumonitis, a severe inflammatory reaction in the lungs occurs in 1:100- 1:1,000 individuals.
  • Seizures from fever side effect: 1:1,000.

Postmarketing Surveillance:

(adverse reactions that have been reported by the public since the introduction of the vaccine)

Varivax FDA Package Insert (frozen):

  • Body as a Whole:  Anaphylaxis (including anaphylactic shock) and related phenomena such as angioneurotic edema, facial edema, and peripheral edema.
  • Eye Disorders:  Necrotizing retinitis (in immunocompromised individuals).
  • Hemic and Lymphatic System:  Aplastic anemia; thrombocytopenia (including idiopathic thrombocytopenic purpura (ITP)).
  • Infections and Infestations:  Varicella (vaccine strain).
  • Nervous/Psychiatric:  Encephalitis; cerebrovascular accident; transverse myelitis; Guillain-Barré syndrome; Bell’s palsy; ataxia; non-febrile seizures; aseptic meningitis; dizziness; paresthesia.
  • Respiratory:  Pharyngitis; pneumonia/pneumonitis.
  • Skin:  Stevens-Johnson syndrome; erythema multiforme; Henoch-Schönlein purpura; secondary bacterial infections of skin and soft tissue, including impetigo and cellulitis; herpes zoster. [8]

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The Bottom Line and the Varicella Vaccine

  • If you decide to vaccinate for varicella, studies have shown that one dose may work as well as the  two doses recommended if the first dose is given at 18 months of age, instead of the recommended 12 months.
  • If your child catches chickenpox, valicyclovir, the medication, may be used to lessen the symptoms.
  • If your teenager or an adult catches the chickenpox, valicyclovir may be used to lessen the symptoms.
  • Even if a teenager has never shown symptoms of chickenpox, they may have a blood test drawn to see if they had been around the virus enough to have built up immunity.
  • If you decide to vaccinate for varicella, DO NOT opt for the ProQuad vaccine (both MMR and Varicella combined), as this vaccine is associated with higher rates of febrile seizures and fever.
  • Do NOT vaccinate your child(ren) for varicella if you are pregnant.
  • “A study of 115,000 children in two health maintenance organizations during 1995–1999 found that children who received varicella vaccine less than 30 days after MMR vaccination had a 2.5–fold increased risk of breakthrough varicella compared with those who received varicella vaccine before, simultaneously with, or more than 30 days after MMR.” [1] This means it may be best to vaccinate for varicella more than 30 days post the MMR vaccine.

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Who should NOT get the Varicella vaccine. [CDC] Back to Top


  1. Epidemiology and Prevention of Vaccine-Preventable Diseases, 12th Edition (The Pink Book) (CDC) (web version)
  2. What Your Doctor May Not Tell You About(TM) Children’s Vaccinations
  3. The Vaccine Book: Making the Right Decision for Your Child (Sears Parenting Library)
  4. Make an Informed Vaccine Decision for the Health of Your Child: A Parent’s Guide to Childhood Shots
  5. Vaccinations: A Thoughtful Parent’s Guide: How to Make Safe, Sensible Decisions about the Risks, Benefits, and Alternatives
  6. Vaccine Epidemic: How Corporate Greed, Biased Science, and Coercive Government Threaten Our Human Rights, Our Health, and Our Children
  7. How to Raise a Healthy Child in Spite of Your Doctor
  8. Merck VARIVAX package insert
  9. Merck ProQuad package insert
  10. Vaccine Ingredient Summary (CDC)
  13. Federal Vaccine Compensation Statistics (US Department of Health and Human Services)
  14. Weibel, R.E.; et al.: Live Attenuated Varicella Virus Vaccine. Efficacy Trial in Healthy Children. N Engl J Med. 310(22): 1409-1415, 1984. 
  15. Arbeter, A.M.; et al.: Varicella Vaccine Trials in Healthy Children. A Summary of Comparative and Follow-up Studies. Am J Dis Child. 138: 434-438, 1984. 
  16. Weibel, R.E.; et al.: Live Oka/Merck Varicella Vaccine in Healthy Children. Further Clinical and Laboratory Assessment. JAMA. 254(17): 2435-2439, 1985.
  17. Chartrand, D.M.; et al.: New Varicella Vaccine Production Lots in Healthy Children and Adolescents. Abstracts of the 1988 Inter-Science Conference Antimicrobial Agents and Chemotherapy: 237(Abstract #731).
  18. Johnson, C.E.; et al.: Live Attenuated Varicella Vaccine in Healthy 12- to 24-Month-Old Children. Pediatrics. 81(4): 512-518, 1988.
  19. Gershon, A.A.; et al.: Immunization of Healthy Adults with Live Attenuated Varicella Vaccine. J Infect Dis. 158(1): 132-137, 1988.
  20. Gershon, A.A.; et al.: Live Attenuated Varicella Vaccine: Protection in Healthy Adults Compared with Leukemic Children. J Infect Dis. 161: 661-666, 1990.
  21. White, C.J.; et al.: Varicella Vaccine (VARIVAX) in Healthy Children and Adolescents: Results From Clinical Trials, 1987 to 1989. Pediatrics. 87(5): 604-610, 1991.
  22. Vázquez M, LaRussa PS, Gershon AA, Niccolai LM, Muehlenbein CE, Steinberg SP, Shapiro ED. Effectiveness over time of varicella vaccine. JAMA. 2004 Feb 18;291(7):851-5.
  23. Kuter B, Matthews H, Shinefield H, Black S, Dennehy P, Watson B, et al. Ten year follow-up of healthy children who received one or two injections of varicella vaccine. Pediatr Infect Dis J. 2004;23:132–7.

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Reviewed/Updated: 07/19
Content Created: 03/14

Vaccine Strategy Guide - Dr. Green Mom
Dr. Green Mom

Dr. Mayer is a naturopathic medical doctor and an expert in nutrition and wellness as it relates to pediatrics and families. Her passion for prevention of disease as cure fueled her desire to immerse herself into specializing in adult onset chronic conditions, as well as childhood chronic illness.

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