The coadministration of a COVID-19 mRNA booster vaccine with a seasonal influenza vaccine was found to be associated with a mild increase in risk for systemic adverse reactions compared with the administration of a COVID-19 mRNA booster vaccine alone, according to results of a study published in JAMA Network Open.
Data for this study were sourced from the v-safe platform, a smartphone-based active surveillance application established by the Centers for Disease Control and Prevention for US residents. In this study, researchers compared the rate of systemic adverse reactions within the first 7 days following vaccination between participants who were coadministered a COVID-19 vaccine booster with a seasonal influenza vaccine vs those who received a COVID-19 booster alone. Comparisons between groups were adjusted for patient age, sex, and week of vaccination receipt.
A total of 92,023 participants received a COVID-19 vaccine booster (Pfizer-BioNTech, n=61,390; Moderna, n=30,633) plus a seasonal influenza vaccine and 889,076 received a COVID-19 booster alone (Pfizer-BioNTech, n=466,439; Moderna, n=422,637). Of these participants, 59.4% to 63.2% were women or girls, 34.1% to 43.5% were aged between 12 and 49 years, 25.1% to 27.3% were between 50 and 64 years, 24.0% to 31.0% were between 65 and 74 years, and 5.3% to 9.2% were 75 years and older.
Among participants who received the Pfizer-BioNTech booster plus influenza vaccine vs those who received the Moderna booster plus influenza vaccine, injection site reactions occurred in 64.9% and 74.4% systemic reactions occurred in 58.9% and 68.6%, and 19.0% and 26.8% reported an impact to their health, respectively. The rates of injection site reactions (64.0% vs 71.7%), systemic reactions (58.9% vs 64.9%), and reports of health impacts (21.0% vs 25.3%) were similar compared with participants who received the Pfizer-BioNTech booster alone vs those who received the Moderna booster alone.
The researchers noted that most systemic adverse reactions were of mild to moderate severity and occurred the day after vaccination. The most common systemic reactions were fatigue, headache, and myalgia.
Compared with participants who received a COVID-19 vaccine booster alone, the risk for any systemic adverse reaction was increased among those who were coadministered either the Pfizer-BioNTech booster (adjusted odds ratio [aOR], 1.08; 95% CI, 1.06-1.10) or the Moderna booster (aOR, 1.11; 95% CI, 1.08-1.14).
Neither the coadministration of the Pfizer-BioNTech (aOR, 0.92; 95% CI, 0.84-1.01) nor Moderna (aOR, 0.94; 95% CI, 0.83-1.07) boosters was associated with an increased risk for requiring subsequent medical care.
This study was limited by potential bias due to the use self-reported data.
According to the researchers, “these results may help better characterize outcomes associated with simultaneously administered COVID-19 mRNA booster and influenza vaccines in the US population.”
Hause AM, Zhang B, Yue X, et al. Reactogenicity of simultaneous COVID-19 mRNA booster and influenza vaccination in the US. JAMA Netw Open. 2022;5(7):e2222241. doi:10.1001/jamanetworkopen.2022.22241