Acute unsolicited adverse events following BNT162b2 vaccine in Saudi Arabia, a real-world data

• Published in: Vaccine Vol. 40; no. 3; pp. 477 - 482
• Main Authors: Almohaya, Abdulellah M., Alsubie, Haya, Alqarni, Bader, Alzayad, Bashayer, Alghar, Ali, Alshahrani, Khalid, Barry, Mazin
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 24-01-2022; Elsevier Limited
• Subjects: Adverse events; Allergies; Anaphylaxis; Anaphylaxis - chemically induced; Anaphylaxis - epidemiology; Blood pressure; BNT162 Vaccine; Collaboration; Comorbidity; Contraindications; Coronavirus; Coronaviruses; COVID-19; COVID-19 vaccines; Demographics; Demography; Dosage; Drug dosages; Female; Humans; Immunization; Medical laboratories; mRNA; mRNA Vaccines; Nanoparticles; Nausea; Novel; Safety; SARS-CoV-2; Saudi Arabia - epidemiology; Severe acute respiratory syndrome coronavirus 2; Statistical analysis; Syncope; Vaccine; Vaccines; Viral diseases; Vital signs; Saudi Arabia; United States > US; Riyadh Saudi Arabia; COVID-19; Coronavirus; Novel; Anaphylaxis; Adverse events; AAE; Vaccine; Safety; Covid-19
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2021.12.001

•Acute adverse events after BNT162b2 vaccination in Saudi Arabia were extremely rare.•For each 10,000-dose administered, 48.4 events are estimated to occur.•Most common adverse events were dizziness, headache, nausea, and/or fatigue.•Female were significantly more likely to develop non-anaphylactic adverse events.•The vast majority of the adverse events were managed with short observation.
Acute adverse events and anaphylaxis were reported after the administration of coronavirus disease (COVID-19) mRNA vaccines. We aim to explore the nature and outcome of adverse events following BNT162B2 vaccine in a community vaccination center, Riyadh, Saudi Arabia.
Within 30 min post vaccination, all acute adverse events (AAEs) that occurred before March 31st, 2021, and in people older than 16 years were reviewed (AAE group). We used the case definition of Brighton collaboration on vaccine safety to define anaphylaxis. Patients’ demographics, comorbidities, allergy history, and outcome at disposition were collected. Observation duration after vaccination was short (<15 min) or extended (<3 h). Statistical analysis was performed to study AAEs association with the study variables and outcomes.
Out of 71,221 vaccine recipients, 144 (0.002%) had developed 345 AAEs, at a rate of 48.4 events per 10,000 dose administered. The majority of cases in AAE group were first dose recipients (93.8%) and previously healthy (59%), while the minority had a previous history of allergy (6.3%) or a laboratory-confirmed COVID-19 (4.2%). We found a significant association between female gender and the occurrence of any AAE (p-value = 0.002). Per every 10,000 doses administered, non-anaphylactic AAEs were dizziness (17.8), headache (9.7), nausea (7.1), or syncope (3.2). Only one in every ten AAEs was considered serious and resulted in an extended observation (4.8 per 10,000 doses), but only 1/144 required hospitalization for non-anaphylaxis reasons (0.1 per 10,000 doses). According to the Brighton collaboration definition of anaphylaxis, no single case of high certainty anaphylaxis was recorded. No death was documented in this cohort.
Acute adverse events due toBNT162b2 vaccinewere rare andmostlynon-seriouswith a tendency to occur more in women. Further prospectivestudieson largervaccine recipientsto evaluatethe incidenceof anaphylaxis in the Saudi population are warranted.