Varicella Vaccine

Mechanism :

Varicella Virus Vaccine is a live, attenuated varicella virus vaccine. The virus was initially obtained from a child with natural varicella, then introduced into human embryonic lung cell cultures, adapted to and propagated in embryonic guinea pig cell cultures and finally propagated in human diploid cell cultures.

Indication :

Active prophylaxis for chicken pox

Contraindications :

Hypersensitivity to any component of the vaccine, in pregnant females, anaphylactic or anaphylactoid reactions to neomycin, febrile respiratory illness or other active febrile infection, patients receiving immunosuppressive therapy, individuals with blood dyscrasias, leukemia, lymphomas of any type, or other malignant neoplasms affecting the bone marrow or lymphatic systems, primary and acquired immunodeficiency states, including AIDS, and in individuals with a family history of congenital or hereditary immunodeficiency.

Dosing :

<12 months:

Not recommended.

>12 months:

Single dose of 0.5 mL SC administered; administer the second dose at 4-6 years; may administer earlier if necessary but not sooner than 3 months if immunocompetent, otherwise 2 doses at least 6 weeks apart.

Catch up vaccination:

7-12 years:

0.5 ml subcutaneously, 2 doses at least 3 months apart. Second dose is considered valid if second dose is administered at least 4 weeks after first.

>13 years:

0.5 ml subcutaneously, 2 doses at least 4 weeks apart.

Adverse Effect :

Swelling, rash, pruritus, erythema may occur. A mild chicken-pox with vesiculopapular rash and a low fever commonly occur after the first injection. Upper respiratory illness, cough, irritability/nervousness, fatigue, disturbed sleep, diarrhea, loss of appetite, vomiting, otitis, diaper rash/contact rash, headache, teething, malaise, abdominal pain, other rash, nausea, eye complaints, chills, lymphadenopathy, myalgia, lower respiratory illness, allergic reactions, stiff neck, heat rash/prickly heat, arthralgia, eczema/dry skin/dermatitis, constipation.

Interaction :

Live Vaccines: As it is a live vaccine it may be given at the same time as other live vaccines or after a minimum interval of 3 weeks. It should not be given within a period of 3 weeks before and 3 months after human immunoglobulin and blood or plasma transfusions. The vaccine should not be given to children <1-year-old, as maternal antibodies may interfere with the response. A tuberculin test should ideally be postponed until 4 weeks have elapsed since immunization.

Hepatic Dose :

No dosage adjustments are recommended.