Pfizer/BioNtech BNT162b2: adverse events and insights from an Australian mass vaccination clinic for COVID-19.

The Pfizer/BioNtech BNT162b2 is a major vaccine used in the Australian COVID-19 immunisation programme. We report on BNT162b2 safety in the observation period in a dedicated vaccination clinic linked to a quaternary teaching hospital. We performed a retrospective review of medical records for 57 842 vaccinations, and describe the model of care and adverse event rate at the clinic during its first 2 months of operation. A total of 243 adverse events following immunisation (0.42% of total vaccine doses) were recorded in the immediate observation period post-vaccination, which were predominantly immunisation stress-related responses. Of the 110 patients who experienced an adverse event with their first dose of the vaccine, 90% returned for their second dose of the vaccine, with 87% not reporting any further adverse reaction with the subsequent dose. Nineteen (0.03% of total doses) people were reviewed for an allergic reaction, of which 10 (53%) reported a history of prior allergies. A female predominance was present in both total adverse reactions (70%) and allergic vaccine reactions (79%). Only two patients experienced anaphylaxis (0.003% of total doses), in keeping with low rates of adverse reactions to the BNT162b2 vaccine in the current literature. Overall, the present study reinforces the safety of BNT162b2 in the Australian population, describes vaccination completion rates after adverse events and identifies predisposing factors for rare allergic reactions to the vaccine.

Halder A ，Imamura H ，Condon S ，Boroughs K ，Nilsson SC ，Anderson T ，Caterson ID ... -  《-》

Prevalence of Allergic Reactions After Pfizer-BioNTech COVID-19 Vaccination Among Adults With High Allergy Risk.

Shavit R ，Maoz-Segal R ，Iancovici-Kidon M ，Offengenden I ，Haj Yahia S ，Machnes Maayan D ，Lifshitz-Tunitsky Y ，Niznik S ，Frizinsky S ，Deutch M ，Elbaz E ，Genaim H ，Rahav G ，Levy I ，Belkin A ，Regev-Yochay G ，Afek A ，Agmon-Levin N ... -  《JAMA Network Open》

Side effects of Pfizer/BioNTech (BNT162b2) COVID-19 vaccine reported by the Birzeit University community.

The Pfizer BioNTech COVID-19 vaccine was the first to receive emergency authorization and approval from the FDA. Therefore, it is preferred by most recipients; however, many people are concerned about the vaccine's side effects. At the time of the study, December 2021, Palestine lacked a national reporting system for monitoring adverse vaccine effects. Therefore, this study investigates the post-vaccine adverse events following the Pfizer/BioNTech COVID-19 Vaccine administration in Palestine and identifies the occurrence, extent, and severity among university staff, employees, and students at Birzeit University. A questionnaire-based retrospective cross-sectional study was conducted using a university website (Ritaj), social media platforms (e.g., Facebook and Telegram), and in-person interviews. The Chi-square, Fisher's exact, and McNemar's tests were used to investigate significant relationships. Data were analyzed using SPSS version 22. In total, 1137 participants completed the questionnaire, 33.2% were males, and the mean age was 21.163 years. All participants received at least one dose of the Pfizer-BioNTech COVID-19 vaccine. Approximately one-third of participants reported no adverse effects after receiving the first, second, or third doses (34%, 33.6%, and 32.5%, respectively). The most commonly reported adverse events were fever, chills, headache, fatigue, pain and swelling at the injection site, muscle pain, and joint pain. Allergic reactions were reported by 12.7% of the participants; furthermore, participants with a history of allergy or anaphylaxis before vaccination had a significantly higher tendency for post-vaccination allergic reactions. Eight participants reported rare side effects, including 7 (0.6%) cases of thrombocytopenia and one (0.1%) case of myocarditis. Males aged less than 20 years and smokers were significantly less likely to complain of adverse events. The number of reported side effects was significantly higher after the second vaccine dose than after the first dose. Finally, participants infected with COVID-19 before vaccination was significantly associated with side effects such as fever, chills, shortness of breath, and persistent cough. In this study, the most common post- BNT162b2 Vaccination reported self-limiting side effects similar to those reported by Pfizer/BioNTech Company. However, higher rates of allergic reactions were reported in this sample. Rare side effects, such as thrombocytopenia and myocarditis, were reported by 8 participants. COVID vaccines have been developed at an accelerated pace, and vaccine safety is a top priority; therefore, standard monitoring through a national adverse event reporting system is necessary for safety assurance. Continuous monitoring and long-term studies are required to ensure vaccine safety.

Abukhalil AD ，Shatat SS ，Abushehadeh RR ，Al-Shami N ，Naseef HA ，Rabba A ... -  《BMC INFECTIOUS DISEASES》

Adverse reactions to BNT162b2 mRNA COVID-19 vaccine in medical staff with a history of allergy.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) vaccination is progressing globally. Several adverse reactions have been reported with vaccination against COVID-19. It is unknown whether adverse reactions to COVID-19 vaccination are severe in individuals with allergies. We administered the COVID-19 vaccine to the medical staff at Yamagata University Hospital from March to August 2021. Subsequently, we conducted an online questionnaire-based survey to investigate the presence of allergy and adverse reactions after vaccination and examine the association between allergy and adverse reactions after immunization. Responses were collected from 1586 to 1306 participants after the first and second administration of the BNT162b2 mRNA COVID-19 vaccine, respectively. Adverse reactions included injection site pain, injection site swelling, fever, fatigue or malaise, headache, chills, nausea, muscle pain outside the injection site, and arthralgia. The frequency of some adverse reactions and their severity were higher, and the duration of symptoms was longer in participants with allergies than in those without allergies. Although several participants visited the emergency room for treatment after the first and second vaccinations, no participant was diagnosed with anaphylaxis. This study suggests that the frequency and severity of adverse reactions after injection of BNT162b2 mRNA COVID-19 vaccine were higher in individuals with allergy; however, no severe adverse reactions such as anaphylaxis or death were observed. These results indicate that individuals with allergic histories may tolerate the BNT162b2 mRNA COVID-19 vaccine.

Inoue S ，Igarashi A ，Morikane K ，Hachiya O ，Watanabe M ，Kakehata S ，Sato S ，Ueno Y ... -  《-》

Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine - United States, December 14-23, 2020.

CDC COVID-19 Response Team ，Food and Drug Administration 《-》