Live Attenuated Nasal-Spray Flu Vaccine Safe in Kids With Asthma

By Reuters Staff

March 31, 2022

NEW YORK (Reuters Health) - School-aged children with persistent asthma can safely receive the quadrivalent live attenuated influenza vaccine (LAIV4) with no increased likelihood of asthma flare compared with the quadrivalent inactivated influenza vaccine (IIV4), new research indicates.

"These data add to the compelling safety record of LAIV in children, including those with persistent asthma," Dr. C. Buddy Creech, director of the Vanderbilt Vaccine Research Program, in Nashville, Tennessee, and colleagues write in Pediatrics.

Currently, a diagnosis of asthma or a wheezing episode in the past year is viewed as a contraindication to LAIV4 (administered as a nasal spray) for children aged 2 and 4 years of age.

Yet, it remains unclear whether LAIV may be appropriate for children aged 5 years and older with asthma, for whom there is currently a "precaution" to receiving LAIV, the researchers note.

They investigated the safety of LAIV4 over two influenza seasons in a randomized controlled trial involving 151 children aged 5 to 17 years with asthma.

Half received IIV4 (injection) and half received LAIV4 and were monitored for asthma symptoms, exacerbations, changes in peak expiratory flow rate (PEFR), and changes in the asthma control test for 42 days after vaccination.

In the per-protocol analysis of 142 children, 18 (13%) suffered an asthma exacerbation within 42 days of vaccination, with no marked difference between groups: eight of 74 (11%) in the LAIV4 group and 10 of 68 (15%) in the IIV4 group had an asthma flare, "meeting the bounds for noninferiority," the researchers report.

"When adjusted for asthma severity, LAIV4 remained noninferior to IIV4. There were no significant differences in the frequency of asthma symptoms, change in PEFR, or childhood asthma control test/asthma control test scores in the 14 days postvaccination between LAIV4 and IIV4 recipients," they report.

Adverse reactions were similar between groups, although sore throat (P=0.051) and myalgia (P<0.001) were more common in the IIV4 group.

"These data support reexamining precautions to using LAIV4 in children with asthma, which could be particularly important during influenza pandemics, at times when IIV4 supplies are limited, in situations of public/school mass vaccination clinics using LAIV, or for children with significant needle aversions," Dr. Creech and colleagues conclude.

The study was supported by the U.S. Centers for Disease Control and Prevention.

SOURCE: Pediatrics, online March 28, 2022.