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CDC Assigns Infants First Priority for MMR Vaccination During Shortage

Kate Traynor

The continued national shortage of measles, mumps, and rubella (MMR) virus vaccine live has prompted the Centers for Disease Control and Prevention (CDC) to recommend deferring the administration of some doses of the product.

In a notice published in the March 8 Morbidity and Mortality Weekly Report (MMWR), CDC's Advisory Committee on Immunization Practices (ACIP) asked health care providers to assess whether they have enough MMR vaccine to cover their patients' first and second childhood doses. If supplies are inadequate, ACIP recommends deferring the second dose, which is usually administered between four and six years of age.

The first childhood MMR vaccine, which is normally given between age 12 and 15 months, should be administered on schedule to protect against measles, the report noted.

The MMWR notice also expanded on a recent recommendation from ACIP to defer the administration of varicella vaccine to infants. ACIP's latest recommendation for varicella vaccination is to administer the first dose to children at 18–24 months of age instead of during their first year.

If varicella vaccine supplies continue to dwindle, ACIP recommends prioritizing vaccination as follows:

  • Health care workers, family contacts of people with an immune deficiency, children 13 years or older, and people at high risk for complications from chickenpox should be first in line to receive the existing vaccine doses. 
  • Next in priority are children ages 5–12 years who are susceptible to the varicella virus, especially school-age children and adolescents age 11 or 12. 
  • Lowest in priority are children ages 2–4 years, although some states may recommend vaccination for children in a child-care center or other setting that puts them at increased risk for varicella-related complications.

Ongoing shortages of other immunization products—diphtheria and tetanus toxoids and pertussis vaccine adsorbed; tetanus toxoid; and pneumococcal vaccine—have similarly led ACIP to recommend temporary alterations to the recommended childhood vaccination schedule. CDC continues to stress that health care providers must keep track of deferred vaccine doses so that patients can be vaccinated when the shortages resolve.