Neurologic adverse events among 704,003 first-dose recipients of the BNT162b2 mRNA COVID-19 vaccine in Mexico: A nationwide descriptive study.

mRNA vaccines against SARS-CoV-2 are remarkably effective. Limited information exists about the incidence of adverse events following immunization (AEFI) with their use. We conducted a prospective observational study including data from 704,003 first-doses recipients; 6536 AEFI were reported, of whom 65.1% had at least one neurologic AEFI (non-serious 99.6%). Thirty-three serious events were reported; 17 (51.5%) were neurologic (observed frequency, 2.4/100,000 doses). At the time of writing this report, 16/17 cases had been discharged without deaths. Our data suggest that the BNT162b2 mRNA COVID-19 vaccine is safe; its individual and societal benefits outweigh the low percentage of serious neurologic AEFI. This information should help to dissipate hesitancy towards this new vaccine platform.

Psychological and Psychiatric Events Following Immunization with Five Different Vaccines against SARS-CoV-2.

BACKGROUND: Despite the high number of vaccines administered against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) worldwide, the information on the psychological/psychiatric adverse events following immunization (AEFI) with these newly developed vaccines remains scarce. OBJECTIVE: To describe the frequency of psychological/psychiatric symptoms among recipients of five different anti-SARS-CoV-2 vaccines and to explore the factors associated with their development reported in the nationwide Mexican registry of AEFI against SARS-CoV-2. METHODS: Descriptive study of all the psychological/psychiatric symptoms, including anxiety, panic attacks, insomnia, and agitation reported to the Mexican Epidemiological Surveillance System from 21 December 2020 to 27 April 2021, among adult (≥18 years old) recipients of 7,812,845 doses of BNT162b2, ChAdOx1 nCov-19, rAd26-rAd5, Ad5-nCoV, or CoronaVac. The factors associated with their development are determined by multivariate regression analysis. RESULTS: There were 19,163 AEFI reports during the study period; amongst them, 191 (1%) patients had psychological/psychiatric symptoms (median age of 41 years, interquartile range of 32-54; 149 [78%] women) for an observed incidence of 2.44 cases per 100,000 administered doses (95% confidence interval [CI] 2.12-2.82), 72.8% of psychiatric AEFIs were reported among recipients of BNT162b2. The median time from vaccination to symptom onset was 35 min (interquartile range: 10-720). Overall, the most common psychological/psychiatric symptoms were anxiety in 129 (67.5%) patients, panic attacks in 30 (15.7%), insomnia in 25 (13%), and agitation in 11 (5.7%). After adjusting for the confounding factors, the odds for developing psychological/psychiatric symptoms were higher for those concurrently reporting syncope (odds ratio [OR]: 4.73, 95% CI: 1.68-13.33); palpitations (OR: 2.47, 95% CI: 1.65-3.70), and dizziness (OR: 1.59, 95% CI: 1.10-2.28). CONCLUSION: In our population, psychological/psychiatric symptoms were extremely infrequent AEFIs. No severe psychiatric AEFIs were reported. Immunization stress-related responses might explain most of the detected cases.

Transient sensory symptoms among first-dose recipients of the BNT162b2 mRNA COVID-19 vaccine: A case-control study.

mRNA-based COVID-19 vaccines are effective; however, persistent vaccine hesitancy is partly due to a misperception of their potential adverse events. Non-specific sensory symptoms (NSSS) following immunization are thought to be mediated by stress-related responses. In this case-control study, we evaluated NSSS from a cohort of 7,812,845 BNT162b2 first-dose recipients, of whom 10,929 reported an adverse event following immunization (AEFI). We found an overall frequency of 3.4% (377 cases) or 4.8 cases per 100,000 doses administered. Anatomically, the arms (61%) and face/neck region (36.2%) were the most commonly affected sites. The control group had significantly higher rates of reactogenicity-associated symptoms, suggesting that NSSS are reactogenicity-independent; in multivariable analysis, healthcare workers reported sensory symptoms less frequently (aOR 0.54; 95% CI 0.40-0.72;p < 0.001). This is the first study describing the topography and associated factors for developing NSSS among BNT162b2 recipients. The benign nature of these symptoms may help dissipate hesitation towards this vaccine.