Live-Live Rule Explanation

Why does MCIR say that this patient/student is overdue/incomplete for MMR or Varicella? It looks to me like he/she should be complete.

It could be the “Live-Live Rule.” Certain vaccines (MMR, Varicella, and Influenza Intranasal) are considered live-virus vaccines. Such vaccines must either be given on the same date, or separated by at least 28 days. Otherwise, the second vaccine will not produce a proper immune response, and it will be considered an invalid dose. The 4-day grace period can be applied to any value in Table 1 of the ACIP General Recommendations. Therefore it can be applied to the interval between two doses of the same live vaccine (e.g., MMR doses 1 & 2 or varicella doses 1 & 2). However, it does not apply to the interval between the doses of two different live vaccines (e.g., MMR & varicella), which should be separated by 28 days. ACIP General Recommendations (see page 6) (2/13/03) More Information.”

For more information, contact your Local Health Department.