Varicella (Chicken Pox) Vaccine

Purpose

To prevent nosocomial transmission of varicella (chicken pox) by immunizing susceptible employees.

General Information

  1. Varicella is a common childhood disease; in the United States approximately 5% of adults remain susceptible.
  2. Varicella is transmitted by the airborne route and is very infectious; nosocomial transmission has been frequently documented.
  3. Varicella does not generally cause severe complications in healthy children, but adults and immunocompromised individuals are at risk for significant complications.
  4. The vaccine is a preparation of live attenuated varicella virus indicated for individuals 12 mos. and older.
  5. Clinical trials done for vaccine testing have demonstrated varicella protective antibodies in over 90% of healthy children who were vaccinated.
  6. Duration of protection is currently unknown; two doses 4-8 weeks apart should be used in individuals 13 years and older.
  7. Because it is a live virus, VARIVAX should not be given to immunocompromised, immunodepressed and immunodeficient people. It is also contraindicated for pregnant women (pregnancy should be avoided for three months after vaccination) and individuals with active, untreated tuberculosis or febrile illness.
  8. Vaccine recipients should avoid close contact with high risk (immunocompromised and newborn) people for three weeks after vaccination.
  9. Vaccine should not be administered to people with history of hypersensitivity to gelatin or neomycin.
  10. Salicylates should be avoided for 6 weeks after vaccination because of the association of Reye's syndrome with salicylate use and natural varicella infection.
  11. Immune globulin of any kind or blood should not be administered within 5 mos. prior to vaccination and for 2 mos. following vaccination. Body substance exposures should be treated according to protocol and varicella vaccination delayed, if possible.
  12. VARIVAX can be administered concomitantly with MMR and DT vaccines.
  13. The efficacy of the vaccine preventing infection or clinical disease after exposure is unknown; vaccine will be administered for that purpose only after consultation with U-M OHS medical director.
  14. The most common side effects are redness and tenderness at injection site, fever and varicella-like rash.
  15. If a vaccine recipient develops a rash within four weeks of administration, (s)he should be off work for 3 days following appearance of rash. Investigation into contacts will not be conducted.

Procedure

  1. All new employees and volunteers will be assessed for history of chicken pox disease or vaccination.
  2. If the individual denies history of disease, vaccination, or is unsure, a varicella titer is drawn. Draw blood in Corvac tube and send to U-M OHS via courier with microbioloby requisition marked for VZV IgG. Call U-M OHS at (734) 764-8021 if you need to obtain microbiology lab requisitions for your site.
  3. Results of the titer or history of disease is documented on activity sheet.
  4. If the titer is negative (less than 1:8), an appointment for vaccination will be made for the employee and the employee will be notified by letter of the appointment.
  5. Employees will be informed at the time of the blood draw that they will not be specifically informed of positive results but will receive a letter if the titer is negative.
  6. If an employee receives a notice that (s)he is non-immune for chicken pox, they should call U-M OHS at (734) 764-8021 to make arrangements to receive the vaccine.
  7. Volunteers with negative titers will be informed of results in writing with recommendation for vaccination or avoidance of exposure.

Vaccine Administration

  1. A consent form must be signed prior to administration. Employee is given the Vaccine Information Statement (VIS). A VIS must be given out prior to administration of the vaccine, and it must be given out each time the vaccine is given. Lot number and injection site are documented on the consent form. Pregnancy should be ruled out by history and LMP.
  2. Employee is advised to look for and report any rash that occurs within four weeks after vaccine administration. If a rash develops, the employee should report to U-M Occupational Health Services. If the rash is felt to be due to the vaccine, the employee is advised to be off work for 2-3 days following appearance of rash. Contact investigation will not be conducted.
  3. Employee is advised to avoid close contact with high risk individuals for three weeks after vaccination.
  4. The vaccine must be stored in a freezer that maintains a temperature of -15 Celsius.
  5. The vaccine should be reconstituted only with the diluent supplied with the vaccine. The diluent is stored at room temperature or in the refrigerator.
  6. To reconstitute, withdraw 0.7 ml of diluent into a syringe and add to the vial of lyophilized vaccine.
  7. Gently agitate to mix thoroughly.
  8. Withdraw the contents into a syringe, change the needle and inject the total volume (approx. 0.5 ml) subcutaneously, preferable into the deltoid area.
  9. Vaccine must be used within 30 minutes of reconstitution.
  10. Employee is given an appointment in 4-8 weeks for second dose.
  11. Vaccination is recorded on consent form and sent to U-M Occupational Health Services.