(Editor's Note: On June 29, the AAFP published a statement supporting the interim recommendation from the CDC's Advisory Committee on Immunization Practices to not use live attenuated influenza vaccine during the 2016-17 flu season.)
During the first day of its June 22-23 meeting, the CDC's Advisory Committee on Immunization Practices (ACIP) voted to recommend that live attenuated influenza vaccine (LAIV; FluMist), which is licensed for use in people ages 2-49 years, should not be used during the 2016-17 flu season.
Their decision was based on data showing that the effectiveness of LAIV from 2013 through 2016 was poor and/or lower than expected, according to a CDC media statement.(www.cdc.gov)
In late May, the U.S. Influenza Vaccine Effectiveness Network released preliminary study data on the effectiveness of LAIV in children ages 2-17 during the 2015-16 influenza season that showed the estimated vaccine effectiveness (VE) against any flu virus was 3 percent (with a 95 percent confidence interval [CI] of -49 percent to 37 percent).
"This 3 percent estimate means no protective benefit could be measured," said the media statement. "In comparison, inactivated influenza vaccine (IIV) had a VE estimate of 63 percent (with a 95 percent CI of 52 percent to 72 percent) against any flu virus among children 2 years through 17 years."
- During the first day of its June 23-24 meeting, the CDC's Advisory Committee on Immunization Practices voted to recommend that live attenuated influenza vaccine (LAIV; FluMist) should not be used during the 2016-17 flu season.
- In late May, the U.S. Influenza Vaccine Effectiveness Network released preliminary data on the effectiveness of LAIV in children ages 2-17 during the 2015-16 influenza season that indicated the estimated effectiveness of the vaccine against any flu virus was 3 percent.
- The CDC said it would work with manufacturers this summer to ensure the supply of inactivated influenza vaccine for the 2016-17 season will be adequate to meet increased demand.
The agency said other non-CDC studies also supported this conclusion that LAIV was far less effective than IIV this past flu season. In addition, these data bolster data from the 2013-14 and 2014-15(www.cdc.gov) flu seasons that also showed poor and/or lower than expected VE for LAIV.
AAFP liaison to the ACIP Margot Savoy, M.D., M.P.H., of Wilmington, Del., told AAFP News it was especially concerning that LAIV lacked effectiveness in providing protection against the influenza A (H1N1) virus, given that the vaccine's target population (children ages 2-8) "coincides with the population most susceptible to severe morbidity and mortality if infected with H1N1."
The ACIP followed up its overall recommendation against use of LAIV with a vote to specifically recommend that the Vaccines for Children program also should not provide LAIV this upcoming flu season.
Implications of ACIP Decision
From an evidence-based medicine perspective, Savoy said this decision is clearly the right thing to do.
"However," she acknowledged, "it does come with some programmatic concerns, which were discussed during the meeting."
Vaccine manufacturers have projected that as many as 176 million doses of flu vaccine in all forms would be available in the United States during the 2016-2017 season. MedImmune, a subsidiary of AstraZeneca and manufacturer of the FluMist vaccine since 2003, had projected it would supply as many as 14 million doses of the nasal spray product this coming season, or about 8 percent of the total U.S. supply.
In a June 23 news release,(www.astrazeneca.com) AstraZeneca said U.S. sales of FluMist Quadrivalent in fiscal year 2015 totaled $206 million. The company also noted it is working with the CDC to better understand the agency's latest data "to help ensure eligible patients continue to receive the vaccine in future seasons."
The ACIP's vote on FluMist could have implications for family physicians who have already preordered their influenza vaccine supply for the 2016-17 season. This is especially true for physicians who planned to administer LAIV to children; data from recent seasons suggest the nasal spray vaccine accounts for about one-third of all flu vaccines given to children.
"You should not use the LAIV you preordered for anyone (adults or children), which is potentially an issue for a bunch of docs," Savoy cautioned. "This vote leaves no room for using LAIV in any population, making that vaccine supply unusable."
In fact, Savoy said, ACIP members discussed the fact that even with needle-phobic, vaccine-hesitant patients, LAIV still could not -- in good conscience -- be recommended.
"Though some influenza coverage is preferable to no coverage at all, LAIV was not actually providing the coverage benefit, and so providing it was simply not appropriate," she said. Instead, she added, "Consider using smaller needles or other distraction techniques during administration for those needle-shy patients."
As for whether the vaccine's manufacturer would make allowances for those who preordered the vaccine, "It was not clear at the time of the meeting if MedImmune would be offering to release physicians from their contractual obligations to purchase LAIV or allowing them to swap the vaccine at no cost for IIV products."
She added that the CDC said it would work with manufacturers this summer to ensure the supply of IIV is adequate to meet the increased demand caused by the absence of LAIV.
According to Savoy, family physician Jamie Loehr, M.D., of Ithaca, N.Y., served as the AAFP liaison on the Influenza Workgroup that reviewed the data on LAIV and presented this recommendation to the ACIP for a vote.
Recent History of LAIV Recommendations
In 2014, the ACIP actually recommended preferential use of LAIV over IIV in healthy children ages 2-8 when the vaccine was immediately available based on data from multiple influenza seasons that suggested FluMist offered better protection for this age group.
Then in 2015, the ACIP chose not to renew its preferential recommendation for LAIV over IIV after additional data failed to confirm the superior effectiveness of LAIV that had been observed in earlier studies.
Savoy said the proposed language "LAIV should not be used in any setting" will now be sent to CDC Director Thomas Frieden, M.D., M.P.H., for final approval. The complete annual recommendations on prevention and control of influenza with vaccines will be published in a CDC Morbidity and Mortality Weekly Report in late summer or early fall.
According to AAFP Senior Vice President for Health of the Public and Interprofessional Activities Julie Wood, M.D., the Academy will follow this issue closely and advise members about influenza vaccine supply issues as the ACIP recommendation is finalized and implemented.
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