Response and Clearance of Viral DNA Following Administration of Live Attenuated Varicella Vaccine.

Study Overview
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Brief Summary
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Varicella zoster virus (VZV) can lead to significant morbidity and mortality in transplant recipients. Current recommendations suggest a 4 week waiting period between vaccination and transplantation and consideration of booster immunizations if antibody response does not reach target levels. This four week waiting period can result in delayed transplant, rejection of an optimal organ, or missed opportunity to vaccinate. However, these recommendations are not evidence based. This is a prospective study to look at the immune response to varicella vaccine in children with chronic liver disease. Investigators will evaluate: the time at which VZV DNA becomes undetectable in blood and saliva by PCR after vaccination in children with chronic liver disease and the difference in humoral and cell mediated immune response to varicella immunization between children with chronic liver disease and healthy children.

Official Title
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Response and Clearance of Viral DNA Following Administration of Live Attenuated Varicella Vaccine in Children With Liver Disease

Conditions
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Varicella, Transplants

Intervention / Treatment
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* Biological: varicella vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 6 months to 21 years no history of varicella, zoster or prior varicella vaccination Exclusion Criteria: acute liver failure liver transplant anticipated within 28 days prior history of receiving blood products or immunoglobulin within 5 months prior to vaccination fever pregnancy immunocompromised status receiving immunosuppressive meds

Ages Eligible for Study
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Minimum Age: 6 Months
Maximum Age: 21 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Healthy Controls<br>Healthy Children ages 6 months-21 years who have not received varicella vaccine and who do not have prior varicella or zoster will receive Varivax. We will then measure 1) markers of humoral immunity at baseline and 4 weeks post vaccination and 2) markers of cell mediated immunity at baseline, 1 week, and 4 weeks post vaccination | Biological: varicella vaccine<br> <br> |
| Children with Chronic Liver Disease<br>Children with chronic liver disease ages 6 months-21 years who have not received varicella vaccine and who do not have prior varicella or zoster will receive Varivax. We will then measure 1) varicella DNA in the blood and saliva at enrollment, 1 week, 2 weeks, 3 weeks, 4 weeks post vaccination 2)markers of humoral immunity at baseline and 4 weeks post vaccination and 3) markers of cell mediated immunity at baseline, 1 week, and 4 weeks post vaccination | Biological: varicella vaccine<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| clearance of viral DNA |  | 4 weeks | 
| humoral response |  | 4 weeks | 
| cell mediated response |  | 4 weeks |