An Unusual Presentation of Erythema Multiforme Following the Administration of Pfizer-BioNTech COVID-19 mRNA Vaccine in a Pediatric Patient.

Coronavirus disease 2019 (COVID-19) caused a global calamity that forced emergency use authorization to Pfizer-BioNTech COVID-19 (BNT162b2) vaccine. It is efficacious in preventing symptomatic severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in seronegative recipients. The safety profile is still unclear; however, commonly reported symptoms post-vaccination are fatigue, headache, muscle pain, chills, and injection-site pain. COVID-19 disease elicits, to some extent, cutaneous side effects like urticaria, morbilliform rash, and chilblain-like eruption. Vaccination against COVID-19 was reported to induce similar dermatologic manifestations, such as urticarial rash, delayed large-local reaction, local injection-site reaction, and morbilliform eruption. Erythema multiforme (EM) is a rare manifestation post-vaccination, and only a few reports implicate it as a culprit in cutaneous eruptions following the BNT162b2 vaccine. This report delineates the presentation of a healthy 14-year-old girl to a dermatology clinic who developed EM post-vaccination with the first dose of BNT162b2. New-onset EM-eruption post-vaccination with BNT162b2 had been reported previously in 14 cases, and one case reported on the flare of preexisting-EM.

Pityriasis Rosea Eruption Following the Administration of Oxford-AstraZeneca Vaccine.

The coronavirus disease 2019 (COVID-19) infection has led to accelerated development and utilization of vaccines to prevent its implications on health. One of these vaccines is a vector-based, Oxford-AstraZeneca Vaccine (AZD1222). Frequently reported side effects are related to host-immune response. While dermatologic manifestation is peculiar in nature and denotes a serious eruption that might defer future vaccination. Herein, we present a case of a medically free 37-year-old female who developed clinical and histological evidence of pityriasis rosea (PR) after administration of a second-dose vaccination of AZD1222. The first dose of vaccination was administered as Pfizer BioNTech COVID-19 mRNA (BNT162b2) vaccine. This case is unique in nature as this patient developed AZD1222-induced PR, while some reports in the literature have linked PR to the BNT162b2 vaccine. This patient continued to receive a booster vaccination with BNT162b2 with no reportable side effects.

Recovery From Central Retinal Artery Occlusion Accompanying Paracentral Acute Middle Maculopathy After COVID-19 Vaccination.

Although ocular complications following COVID-19 vaccination have been reported, particularly retinal vascular occlusion and uveitis, their definitive causal relationships remain uncertain. This report presents a case of central retinal artery occlusion (CRAO) with paracentral acute middle maculopathy (PAMM) developed one day after receiving Pfizer COVID-19 vaccine, with a favorable outcome. The patient experienced sudden vision loss in her left eye, and her vision dropped to hand motion the day after vaccination. The initial examination suggested CRAO, but optical coherence tomography (OCT) revealed PAMM. We administered intravenous d-mannitol and acetazolamide and performed ocular massage. Two days later, her corrected visual acuity improved to 0.4, and further improvement to 1.2 occurred after 16 days. To the best of our knowledge, no reports have documented CRAO with PAMM following mRNA COVID-19 vaccination. The relationship between COVID-19 vaccination and retinal vascular occlusion remains unknown, highlighting the need for further research.

A Case of Concurrent Acute Macular Neuroretinopathy and Paracentral Acute Middle Maculopathy Following Pfizer-BioNTech COVID-19 Vaccination.

We present a 65-year-old woman who developed sudden and severe vision loss in her left eye one day after the administration of the second dose of COVID vaccine. The best corrected visual acuity in this eye was 1/10. Diffuse paracentral acute middle maculopathy was detected on spectral domain optical coherence tomography (OCT). OCT angiography images revealed concurrent vascular flow defects consistent with acute macular neuroretinopathy in the deep retinal capillary plexus and choriocapillaris layers. At the end of the six-month follow-up, there was no improvement in visual acuity, and atrophy and thinning developed in all layers of the retina.

Bilateral Axillary Lymphadenopathy After COVID-19 Vaccine Presenting for Lymph Node Surgical Biopsy: A Case Report.

The coronavirus disease 2019 (COVID-19) pandemic ravaged China, made its way to Thailand and Japan, and ultimately spread across the globe. Despite all efforts to contain the virus, hundreds of millions of positive cases and millions of deaths have been reported worldwide. Due to the vastness and severity of this virus, there was a desperate need for a vaccine, quickly. The COVID-19 vaccination was created urgently under emergency use authorization (EUA) by the US Food and Drug Administration (FDA) in less than one year, a process typically taking over 10 years. With this expedited creation time, there is also a shortened time frame for clinical trials, which is commonly used to evaluate for effectiveness and identify any potential side effects or adverse reactions to the created vaccine. We will discuss some potential side effects of receiving the Pfizer-BioNTech COVID-19 mRNA vaccination. In this case report, we discuss one individual who received two doses of the Pfizer-BioNTech COVID-19 mRNA vaccine and experienced a previous unreported adverse side effect of non-self-remitting bilateral axillary lymphadenopathy. This reaction was not originally seen during the clinical trial phase of the vaccine creation, which caused this individual to obtain a full medical workup including ultrasound, computed tomography (CT) scans, and blood work and ultimately needing surgical intervention to have the axillary lymphadenopathy excised. We aim to shed light on a new, undocumented adverse reaction that should be included in physicians' differential diagnoses in individuals after receiving the COVID-19 vaccine, particularly the Pfizer-BioNTech COVID-19 mRNA vaccination. This information could help future patients avoid unnecessary extensive medical workups, surgical procedures, being exposed to anesthesia, or having the burden of additional unwarranted healthcare costs.

Comparison of Immunogenicity and Reactogenicity of Five Primary Series of COVID-19 Vaccine Regimens against Circulating SARS-CoV-2 Variants of Concern among Healthy Thai Populations.

To compare immunogenicity and reactogenicity of five COVID-19 vaccine regimens against wild-type SARS-CoV-2 and variants of concern (VoCs) among Thai populations, a prospective cohort study was conducted among healthy participants aged ≥18 years who had never been infected with COVID-19 and were scheduled to get one of the five primary series of COVID-19 vaccine regimens, including CoronaVac/CoronaVac, AZD1222/AZD1222, CoronaVac/AZD1222, AZD1222/BNT162b2, and BNT162b2/BNT162b2. Anti-receptor binding domain (anti-RBD-WT) IgG and neutralizing antibody (NAb-WT) against wild-type SARS-CoV-2 were measured at pre-prime, post-prime, and post-boost visits. NAb against VoCs (NAb-Alpha, NAb-Beta, NAb-Delta, and NAb-Omicron) were assessed at the post-boost visit. Adverse events (AEs) following vaccination were recorded. A total of 901 participants (CoronaVac/CoronaVac: 332, AZD1222/AZD1222: 221, CoronaVac/AZD1222: 110, AZD1222/BNT162b2: 128, and BNT162b2/BNT162b2: 110) were enrolled. Anti-RBD-WT IgG and NAb-WT levels increased substantially after each vaccine dose. At the post-boost visit, BNT162b2/BNT162b2 induced the highest GMC of anti-RBD-WT IgG level (1698 BAU/mL), whereas AZD1222/BNT162b2 induced the highest median NAb-WT level (99% inhibition). NAb levels against VoCs, particularly the Omicron strain, were markedly attenuated for all vaccine regimens (p < 0.001). Overall, no serious AEs following vaccination were observed. All five primary series of COVID-19 vaccine regimens were well-tolerated and elicited robust antibody responses against wild-type SARS-CoV-2 but had attenuated responses against VoCs, particularly the Omicron strain, among healthy Thai populations.

A comparison of the effect on pain management of two non-pharmacological methods used during administration of Pfizer-BioNTech COVID-19 vaccine (BNT162b2): A randomized controlled study.

AIMS: This study was conducted with the aim of examining the effect on pain intensity of the vibration technique applied at the injection site and squeezing a stress ball during the administration of Pfizer-BioNTech COVID-19 vaccination. METHODS: This was a randomized controlled single-blind experimental study. The study included 120 adults who were randomly selected between July and November 2022. One experimental group (n = 40) received local vibration by means of a Buzzy® device, and the other (n = 40) were given a stress ball to squeeze. Routine vaccination procedure was performed with the control group (n = 40). The level of pain felt during the vaccination procedure was assessed on a visual analog scale. RESULTS: The pain score of individuals during the vaccination procedure was found to be significantly lower in the vibration group than in the control group (P = .005) and the stress ball group (P = .036), but there was no significant difference between the control and stress ball groups (P = .851). Also, it was found that the variables of gender, age and body mass index did not affect the average pain intensity of individuals during the vaccination procedure. CONCLUSIONS: It was found that local vibration applied by means of the Buzzy® device was effective in reducing the levels of pain relating to administration of the Pfizer-BioNTech COVID-19 vaccination. Nurses should think of the application of vibration as a choice in the management of pain relating to Pfizer-BioNTech COVID-19 vaccination.

Syncope With Sinus Arrest Following a Single Dose of a COVID-19 Vaccine.

Vaccines against the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) are of paramount importance in combating the current coronavirus disease 2019 (COVID-19) pandemic. Syncopal episodes following routine vaccinations are well-reported; however, only a few cases of syncope following SARS-CoV-2 vaccines exist in the literature. This is a case report of a 21-year-old female patient who developed recurrent syncopal attacks over three months that started one day after receiving the first dose of the Pfizer-BioNTech COVID-19 vaccine (Pfizer, New York City; BioNTech, Mainz, Germany). Holter monitoring during successive episodes showed progressive bradycardia followed by a prolonged sinus arrest. The patient eventually required pacemaker placement that resulted in the total resolution of her symptoms. Further studies are required to investigate a possible correlation and the mechanisms involved.

Polyarteritis Nodosa Following mRNA-1273 COVID-19 Vaccination: Case Study and Review of Immunological Mechanisms.

Numerous post-vaccine complications have been reported secondary to the COVID-19 vaccine. Many of these complications are believed to be due to a hyperactive immune system. A 59-year-old woman developed diffuse abdominal pain two days after receiving the mRNA-1273 COVID-19 vaccine (Moderna). A computerized tomography (CT) angiogram of the abdomen and pelvis revealed the presence of numerous vascular irregularities in the celiac axis, bilateral renal arteries, and inferior mesenteric artery consistent with polyarteritis nodosa (PAN), a medium-vessel vasculitis. The patient was managed with intravenous methylprednisolone 500 mg daily for three days and was then placed on oral methotrexate (MTX) 12.5 mg daily for immunosuppressive maintenance treatment. Until now, a limited number of cases of polyarteritis nodosa secondary to the COVID-19 vaccine have been reported. Major mechanisms of post-vaccine autoimmunity are molecular mimicry and autoantibody production. Although rare adverse events from COVID-19 vaccination are possible, there remains an immense benefit to vaccination in preventing COVID-19-related morbidity and mortality.

New-onset retroperitoneal fibrosis following COVID-19 mRNA vaccination: Coincidental or vaccine-induced phenomenon?

The Pfizer-BioNTech mRNA vaccine is a US Food and Drug Administration-approved coronavirus disease 2019 (COVID-19) vaccine. Although it is reported to be safe and effective, immune dysregulation leading to autoimmunity has become an area of concern. Retroperitoneal fibrosis (RPF) is an immune-mediated fibroinflammatory disease characterized by the deposition of fibrous tissues, primarily around the abdominal aorta and iliac arteries. Herein, we report a case of RPF following Pfizer BioNTech COVID-19 mRNA vaccination. To the best of our knowledge, there have been no published reports on RPF after COVID-19 mRNA vaccination. A 58-year-old woman with no history of autoimmune diseases presented with acute onset of epigastric pain 5 weeks after the second dose of the Pfizer-BioNTech vaccine. She had been diagnosed with stage I breast cancer 9 years ago and was in complete remission on admission. Abdominal computed tomography showed preaortic soft-tissue infiltration around the origin of the superior mesenteric artery but no evidence of breast cancer recurrence. Considering the temporal relationship between current symptoms and vaccination and the absence of other possible causes, she was diagnosed with RPF secondary to Pfizer-BioNTech vaccine-induced autoimmunity. This case may raise awareness of the possibility of RPF development following COVID-19 mRNA vaccination.

Suspected COVID-19 mRNA Vaccine-Induced Postural Orthostatic Tachycardia Syndrome.

We present a case of a 15-year-old South Asian male who developed suspected postural orthostatic tachycardia syndrome (POTS) two weeks after receiving the Pfizer-BioNTech coronavirus disease 2019 (COVID-19) vaccine booster, which was successfully managed with low-dose fludrocortisone and ivabradine. Clinicians should be aware of the Pfizer-BioNTech COVID-19 vaccine being implicated with the onset of POTS.

The association between COVID-19 vaccination and idiopathic sudden sensorineural hearing loss, clinical manifestation and outcomes.

PURPOSE: Previous data demonstrated an increased incidence of Idiopathic Sensorineural Hearing Loss (ISSNHL) in 2021 compared to 2019-2020, suggesting an association with the anti-COVID-19 vaccine. We aimed to assess our center's incidence and compare the clinical manifestations and outcomes of vaccinated vs. unvaccinated patients. METHODS: A retrospective chart review of all patients diagnosed with ISSNHL during 2021 was conducted and compared to patients who presented in 2018-2020. Patient demographics, audiometry features, vaccination status, and prognosis were evaluated. RESULTS: Throughout 2021, 51 patients were diagnosed with ISSNHL, compared with 31 during 2020, 38 in 2019, and 41 in 2018, demonstrating a 64%, 34%, and 24% increase, respectively. Among patients who presented in 2021, 13 (25.4%) received the anti-COVID-19 vaccine within 30 days before their presentation, and 4 received it within 96 h. Most presented after receiving the second or third dose. Patient characteristics, audiometry features, and prognosis did not significantly differ between vaccinated and unvaccinated patients. CONCLUSIONS: A marked incline was seen in the 2021 ISSNHL incidence at our medical center, of which 25% of cases were within a month post-anti-COVID-19 vaccination. No significant difference was found in clinical manifestations and outcomes between vaccinated and nonvaccinated patients. While other justifications could be sought, an association cannot be ruled out, and further research is needed.

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

BACKGROUND: 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. METHOD: 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. RESULTS: 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. CONCLUSION: 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.

The Adverse Reactions of Pfizer BioNTech COVID-19 Vaccine Booster Dose are Mild and Similar to the Second Dose Responses: A Retrospective Cross-Sectional Study.

Background: Like other vaccines, Pfizer BioNTech's COVID-19 vaccine efficacy against SARS-CoV-2 virus infections begins to decline within a few months after the 2nd dose. On August 12, 2021, the FDA allowed additional Pfizer BioNTch's COVID-19 vaccine dose (3rd or booster dose) for individuals with weakened immunity. This study aimed to evaluate the short-term adverse reactions (ADRs) of the 2nd and the 3rd doses of the Pfizer BioNTech COVID-19 vaccine. Methods: Information for this study was collected by Google Form questionnaire (online survey). The results included responses from 442 people, the majority from Saudi Arabia. Results: The most common local ADRs following the 3rd dose were injection site pain, injection site hypersensitivity, and axillary lymph node swelling. The most common systemic ADRs were fatigue, muscle pain, bone pain, headache, and fever less than 38ºC. Less common systemic ADRs were shivering, fever more than 38ºC, nasal congestion and rhinorrhea, arrhythmia, cough, abdominal pain, chest tightness, nausea, diarrhea, vomiting, and tachypnea. Rare systemic ADRs were constipation, dizziness and vertigo, lack of concentration, sore throat, excessive hair loss, dysmenorrhea and heavy menstruation, and Bell's palsy. Severe allergic reactions were reported by 2.6% of participants after the 2nd dose, compared with none after the 3rd dose. Nasal congestion and runny nose are more frequent after the 3rd dose. The ADRs of the 2nd and 3rd doses were significantly more prevalent in females. 12% of participants reported ADRs lasting more than one week after the 3rd dose compared to 5% after the 2nd dose. People ≤ 60 years were more affected by the vaccine ADRs. Conclusion: Most of the ADRs reported after the 3rd vaccine dose were consistent with the Pfizer vaccine information sheet and similar to the 2nd dose ADRs.

Serious adverse events of special interest following mRNA COVID-19 vaccination in randomized trials in adults.

INTRODUCTION: In 2020, prior to COVID-19 vaccine rollout, the Brighton Collaboration created a priority list, endorsed by the World Health Organization, of potential adverse events relevant to COVID-19 vaccines. We adapted the Brighton Collaboration list to evaluate serious adverse events of special interest observed in mRNA COVID-19 vaccine trials. METHODS: Secondary analysis of serious adverse events reported in the placebo-controlled, phase III randomized clinical trials of Pfizer and Moderna mRNA COVID-19 vaccines in adults (NCT04368728 and NCT04470427), focusing analysis on Brighton Collaboration adverse events of special interest. RESULTS: Pfizer and Moderna mRNA COVID-19 vaccines were associated with an excess risk of serious adverse events of special interest of 10.1 and 15.1 per 10,000 vaccinated over placebo baselines of 17.6 and 42.2 (95 % CI -0.4 to 20.6 and -3.6 to 33.8), respectively. Combined, the mRNA vaccines were associated with an excess risk of serious adverse events of special interest of 12.5 per 10,000 vaccinated (95 % CI 2.1 to 22.9); risk ratio 1.43 (95 % CI 1.07 to 1.92). The Pfizer trial exhibited a 36 % higher risk of serious adverse events in the vaccine group; risk difference 18.0 per 10,000 vaccinated (95 % CI 1.2 to 34.9); risk ratio 1.36 (95 % CI 1.02 to 1.83). The Moderna trial exhibited a 6 % higher risk of serious adverse events in the vaccine group: risk difference 7.1 per 10,000 (95 % CI -23.2 to 37.4); risk ratio 1.06 (95 % CI 0.84 to 1.33). Combined, there was a 16 % higher risk of serious adverse events in mRNA vaccine recipients: risk difference 13.2 (95 % CI -3.2 to 29.6); risk ratio 1.16 (95 % CI 0.97 to 1.39). DISCUSSION: The excess risk of serious adverse events found in our study points to the need for formal harm-benefit analyses, particularly those that are stratified according to risk of serious COVID-19 outcomes. These analyses will require public release of participant level datasets.

Severe Rhabdomyolysis Complicated With Acute Kidney Injury Required Renal Replacement Therapy After Pfizer COVID-19 Vaccine  .

The adverse effects of coronavirus disease 2019 (COVID-19) vaccines are somewhat common but rarely life-threatening. Diagnosing life-threatening vaccine-related adverse effects is heavily dependent on history taking and ruling out the other possible causes. Vaccine-related complications vary, so awareness of possible complications can lead to efficient management. We present the case of a 58-year-old woman with a history of schizophrenia who received the COVID-19 Pfizer vaccine and developed severe rhabdomyolysis. She required renal replacement therapy and fully recovered with possible transient autoimmune activity. This case highlights the importance of early awareness of adverse effects following vaccine administration and careful history taking and monitoring to avoid life-threatening conditions.

Generalized Papulovesicular Eruption as a Side Effect of the Pfizer-BioNTech COVID-19 Vaccine.

COVID-19 is inflicted by SARS-CoV-2 and resulted in a global health crisis that necessitated the urgency of vaccine development to prevent its spreading among the public. Pfizer-BioNTech COVID-19 is one of the emergency use authorized (EUA) vaccines. This vaccine is efficacious against the SARS-CoV-2 virus; nonetheless, recipients have frequently reported side effects. Recipients of this vaccine experienced miscellaneous side effects like fatigue and headache. However, cutaneous eruptions of varying degrees of severity and involvements have been manifesting post-vaccination. Dermatological eruptions following vaccination against COVID-19 disease are poorly recognized. Dermatological manifestations triggered post-vaccination differ in the clinical context and patient's demographic features. The only constant factor is various clinical and histopathological relations to establish the diagnosis of cutaneous eruption post-vaccination. Herein, we report a case of an 18-year-old male with T-cell acute lymphocytic lymphoma (ALL) in remission since August 2018 and other comorbidities. After the administration of the first dose of the Pfizer-BioNTech COVID-19 vaccine, the patient developed pruritic eczematous eruption presenting as grouped erythematous-violaceous papulovesicular lesions with fine scales over his upper and lower extremities. These eruptions started two days after the administration of the vaccine. This eruption became generalized 21 days after receiving the second dose of the Pfizer-BioNTech COVID-19 vaccine. Clinical suspicion of the drug-induced vesicular eruption was suspected; thus, a biopsy was obtained and showed erosions and mixed inflammatory cell infiltrate. From a clinical and histopathological correlation, vesicular eruption following vaccination with Pfizer-BioNTech COVID-19 was confirmed. Nevertheless, other diagnoses cannot be ruled out, but from the clinical-histopathological association, the vaccine-inflicted eruption is the likely culprit. Reports are crucial to understanding the nature of such dermatological manifestation after emerging diseases and counteractions like vaccinations. The dermatological manifestations are vaguely recognized; thus, by reporting on the cases similar to the case in this report, more data will be available to understand the nature and underlying cause of such eruptions.

A Three-Case Series of Thrombotic Deaths in Patients over 50 with Comorbidities Temporally after modRNA COVID-19 Vaccination.

Coronavirus disease 2019 (COVID-19) is the most dramatic pandemic of the new millennium; to counteract it, specific vaccines have been launched in record time under emergency use authorization or conditional marketing authorization by virtue of a favorable risk/benefit balance. Among the various technological platforms, there is that exploiting a nucleoside-modified messenger RNA (modRNA), such as Comirnaty®, and that which is adenoviral vector-based. In the ongoing pharmacovigilance, the product information of the latter has been updated about the risk of thrombotic thrombocytopenia, venous thromboembolism without thrombocytopenia and immune thrombocytopenia without thrombosis. However, from an in-depth literature review, the same adverse events can rarely occur with modRNA vaccines too. In support of this, we here report a three-case series of thrombotic deaths in patients over 50 with comorbidities temporally after Comirnaty®, investigated by means of post-mortem histopathology and immunohistochemistry. In two out of three cases, the cause of death is traced back to pulmonary microthromboses rich in activated platelets, quite similar morphologically to those described in patients who died from severe COVID-19. Even if remote in the face of millions of administered doses, clinicians should be aware of the possible thrombotic risk also after Comirnaty®, in order to avoid a misdiagnosis with potentially lethal consequences. Since COVID-19 vaccines are inoculated in subjects to be protected, maximum attention must be paid to their safety, and prophylactic measures to increase it are always welcome. In light of the evidence, the product information of modRNA COVID-19 vaccines should be updated about the thrombotic risk, as happened for adenoviral vector-based vaccines.

Branch Retinal Artery Occlusions, Paracentral Acute Middle Maculopathy and Acute Macular Neuroretinopathy After COVID-19 Vaccinations.

Purpose: Potential retinal adverse events after COVID-19 vaccinations reported previously include paracentral acute middle maculopathy (PAMM), acute macular neuroretinopathy (AMN), and central serous chorioretinopathy. We report four cases of branch retinal artery occlusion (BRAO), one case of PAMM, and one case of AMN that occurred after administration of the Pfizer-BioNTech COVID-19 vaccine. Patients and Methods: We retrospectively reviewed the medical records of six patients who presented to Yame General Hospital or Oita University Hospital from July through October 2021. Results: Four patients (2 males) presented with visual field defects associated with BRAO, one male patient with PAMM, and one female patient with AMN after receiving the Pfizer-BioNTech COVID-19 vaccine. The mean age was 59.3 years; the mean best-corrected visual acuity was 20/21. The mean time from the last vaccination to the onset of visual field defect was 22.8 days. Five patients had received two doses of the vaccine and one patient one dose. Patients' medical history included diabetes mellitus in case 2, hypertension in cases 2, 3 and 6, and Alport syndrome and end-stage renal disease in case 6 for which the patient was undergoing regular hemodialysis. Conclusion: Although rare, retinal adverse events may occur after COVID-19 vaccinations. Further studies with a larger sample size should determine whether these retinal abnormalities are causally associated with COVID-19 vaccinations or just coincidental. Potential risks of BRAO/PAMM/AMN after COVID-19 vaccinations must be carefully weighed against the substantial benefit of COVID-19 vaccinations.

Neurological Conditions Following COVID-19 Vaccinations: Chance or Association?

Coronavirus disease 2019 (COVID-19) has been labeled a global pandemic with the first reported case of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurring in Wuhan, China in December 2019. To combat the alarming, increasing rate of those affected by the virus, vaccine development ensued. As mass vaccination initiatives against COVID-19 ensued, adverse reactions began emerging. This non-consecutive, population-based case series focuses on four vaccine-associated neurological adverse events across the central and peripheral nervous system detailing the diagnosis, treatment and subsequent follow-up management. These four patients presented to public and private hospitals in Trinidad and Tobago with new-onset neurological diseases soon after their first doses of a COVID-19 vaccine: two after the Pfizer-BioNTech vaccine (one case of new-onset seizures and one case of longitudinally extensive transverse myelitis) and two after the ChAdOx1 nCoV-19 vaccine (one case of Guillain-Barre syndrome and one case of meningitis-retention syndrome). The background incidence rates of neurological conditions in the population and the large numbers of persons being vaccinated means that some of these conditions will appear in the post-vaccination window by chance. Hence, establishing causal links is difficult. The close temporal relationship between vaccination and the presenting symptoms, the biological plausibility, and the extensive diagnostic workup to exclude other causes fulfill criteria provided by the World Health Organization for causality assessment of an adverse event following immunization on an individual level. On this basis, it was determined that these adverse events were likely due to the vaccines. However, establishing causal links on a population level requires large epidemiological studies and cannot be done on individual case reports alone. While physicians should be cognizant of even these rare adverse events of vaccines, it should be reiterated that the overall safety profile of vaccines is well established.