1689. Safety of Live Attenuated Influenza Vaccine Versus Inactivated Influenza Vaccine in Asthmatic Children
Session: Oral Abstract Session: Vaccines in the Young and Vulnerable
Friday, October 28, 2016: 3:00 PM
Room: 388-390
Background: The Advisory Committee on Immunization Practices has cautioned against use of live, attenuated influenza vaccine (LAIV) in children with asthma, yet limited data on LAIV safety in such children exists. We investigated whether LAIV compared with inactivated influenza vaccine (IIV) is associated with increased asthma exacerbation in children with pre-existing asthma.

Methods: We identified all IIV and LAIV immunizations between July 1, 2007 and March 31, 2014 among Kaiser Permanente Northern California members aged 2 to <18 years with a history of asthma. We categorized children by asthma severity at time of immunization: “active, persistent”; “active, not-persistent”; “remote history”. We defined asthma exacerbation as a hospitalization or ED visit which received a principal diagnosis of asthma. In children with remote history of asthma, we also analyzed chart-confirmed outpatient exacerbations. Using a case-centered approach, we calculated the odds of being vaccinated in the exposure interval (1 to ≤ 14 days) and the odds of being vaccinated in the comparison interval (29 to ≤42 days) prior to the asthma exacerbation, separately for LAIV and IIV, and calculated the ratio of those odds (OR). We also examined whether the OR differed between children receiving LAIV and those receiving IIV (“difference-in differences”).

Results: Among 387,633 immunizations, 85% were IIV and 15% were LAIV. Children getting LAIV vs. IIV were less likely to have active, persistent, asthma (25% vs. 44%), and more likely to have remote history of asthma (47% vs. 28%). Among IIV-vaccinated asthmatic children, the OR of an asthma exacerbation was 0.97 (95% CI: 0.82 to 1.15). Among LAIV-vaccinated asthmatic children the OR was 0.38 (95% CI: 0.17 to 0.90). In the difference-in-differences analysis, LAIV versus IIV was associated with a decreased risk of asthma exacerbations (OR: 0.40, CI: 0.17 to 0.95). Analyzing outpatient exacerbations found no differences between the vaccines.

Conclusion: Among children and adolescents with a history of asthma, we found no evidence that LAIV was associated with an increased risk of asthma exacerbations regardless of severity. This study suggests that concerns about administering LAIV to children with asthma may not be warranted.

G.Thomas Ray, MBA1, Ned Lewis, MPH1, Kristin Goddard, MPH1, Pat Ross, BA1, Frank Destefano, MD, MPH2, Jonathan Duffy, MD2, Roger Baxter, MD, FIDSA1 and Nicola P. Klein, MD, PhD1, (1)Kaiser Permanente Vaccine Study Center, Oakland, CA, (2)Immunization Safety Office, Centers for Disease Control and Prevention, Atlanta, GA


G. T. Ray, Pfizer: Analyst working with Grant Investigator , Research support
Merck: Analyst working with Grant Investigator , Research support

N. Lewis, None

K. Goddard, None

P. Ross, None

F. Destefano, None

J. Duffy, None

R. Baxter, GSK: Grant Investigator , Research grant
Sanofi Pasteur: Grant Investigator , Research grant
MedImmune: Grant Investigator , Research grant
Protein Sciences: Grant Investigator , Research grant

N. P. Klein, GlaxoSmithKline: Grant Investigator , Research grant
Merck & Co: Grant Investigator , Research grant
Pfizer: Grant Investigator , Research grant
Sanofi Pasteur: Grant Investigator , Research grant
MedImmune: Grant Investigator , Research grant
Novartis (now GSK): Grant Investigator , Research grant
Protein Science: Grant Investigator , Research grant

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