Safety of live attenuated influenza vaccine (LAIV) in children and adults with asthma: a systematic literature review and narrative synthesis

Introduction: Asthma is one of the most common chronic respiratory conditions worldwide and can be exacerbated by influenza. Findings from early trials demonstrated a higher risk of medically significant wheezing in otherwise healthy young children (aged 6 − 23 months) following administration of the Ann Arbor-backbone live attenuated influenza vaccine (LAIV-AA). In more recent years, several additional studies have investigated the safety of LAIV-AA in older children (2 − 17 years of age) and adults with asthma or prior wheezing, but these findings have not yet been systematically evaluated. Areas covered: We conducted a systematic literature review to assess and synthesize the evidence from all available studies on the safety of LAIV-AA in people aged 2 − 49 years with a diagnosis of asthma or recurrent wheezing. Expert opinion: Fourteen studies over 20 years, involving a total of 1.2 million participants, provided evidence that LAIV-AA was well tolerated with no safety concerns in individuals aged 2 − 49 years with a diagnosis of asthma or recurrent wheezing. These data can help inform guidelines for use of LAIV-AA in children and adults with a history of asthma or recurrent wheezing.