In a recent report released by the CDC, a panel of health experts revealed that early safety findings from v-safe (a voluntary smartphone-based U.S. safety surveillance system established by the CDC to monitor adverse events after COVID-19 vaccination) and the Vaccine Adverse Event Reporting System (VAERS) for bivalent booster doses administered to individuals aged 12 years and older during the first 7 weeks of vaccine availability are comparable to those previously described for monovalent vaccine booster vaccines.

Additionally, the adverse events reported after a bivalent booster dose seem to be consistent with those reported after a monovalent booster and are less common and less serious than health impacts correlated with COVID-19 illness.

Data revealed that during August 31, 2022, to October 23, 2022, 211,959 v-safe registrants aged 12 years and older reported receiving an age-appropriate bivalent booster dose, including 1,464 (0.7%) who were aged 12 to 17 years; 68,592 (32.4%) who were aged 18 to 49 years; 59,209 (27.9%) who were aged 50 to 64 years; and 82.694 (39.0%) who were aged 65 years and older.

Most registrants indicated that a bivalent booster dose was their fourth (96,241; 45.4%) or fifth (106,423; 50.2%) COVID-19 vaccine dose; 122,953 (58.0%) received a Pfizer-BioNTech bivalent booster dose; and 89,065 (42.0%) received a Moderna bivalent booster dose. More than one-third (84,450; 39.8%) of registrants reported receiving at least one other vaccination at the same visit as bivalent booster vaccination; 83,005 (98.3%) received influenza vaccine.

In the week after receiving the bivalent booster dose, the frequency of local injection-site reaction reports ranged from 49.7% among adults aged 65 years and older to 72.9% among adults aged 18 to 49 years. The prevalence of reported systemic reactions ranged from 43.5% among adults aged 65 years and older to 67.9% among adults aged 18 to 49 years. The most frequently reported reactions among these age groups after bivalent booster dose vaccination were injection-site pain (range: 45.0%-70.5%), fatigue (30.0%-53.1%), headache (19.7%-42.8%), myalgia (20.3%-41.3%), and fever (10.2%-26.3%).

Reported incapacity to complete normal daily activities ranged from 10.6% among adults aged 65 years and older to 19.8% among adults aged 18 to 49 years. Receipt of medical care was reported by 0.8% of registrants; most received care via telehealth (0.3%) or clinic (0.3%) appointment. Hospitalization was reported by 55 (0.03%) registrants.

Most VAERS reports (5,291; 95.5%) were classified as nonserious, including 2,762 (94.3%) after Pfizer-BioNTech and 2,530 (96.8%) after Moderna bivalent booster vaccination. The most commonly reported events among nonserious reports were headache (628; 11.9%), fatigue (575; 10.9%), fever (561; 10.6%), pain (524; 9.9%); and chills (459; 8.7%).

Among 251 VAERS reports classified as serious, five were reports of myocarditis, four were reports of pericarditis, and 20 were reports of COVID-19 disease. The age range of those who experienced myocarditis or pericarditis was 12 to 78 years and 46 to 78 years, respectively. Thirty-six deaths were reported; median age of decedents was 71 years (range: 46-98 years). For the four reports of death with sufficient information for review at the time of this report, cause of death included cardiac arrest, dementia, metastatic prostate cancer, and myocardial infarction. The CDC has requested medical and vital records for the remaining decedents.

The panel wrote, “Health care providers and patients can be reassured that adverse events reported after a bivalent booster dose are consistent with those reported after monovalent doses. Health impacts after COVID-19 vaccination are less frequent and less severe than those associated with COVID-19 illness. CDC and FDA will continue to monitor vaccine safety and will provide updates as needed to help guide COVID-19 vaccination recommendations. “

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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