Retinal artery occlusion following CoronaVac injection in a 45-year-old Filipino.

Background: While complex public health challenges and the emergence of variants have impeded responses to the COVID pandemic, vaccines continue to represent a crucial tool in mitigating the risk of morbidity and mortality. Safety issues weigh heavily upon both the utility and acceptability of every vaccine. Reports of sight-threatening events are scarce. Case description: We report the case of a hypertensive 45-year-old Filipino who noted unilateral (right eye) blurring of vision within 48 hours of his first dose of CoronaVac (Sinovac, China), an inactivated SARS-CoV-2/COVID-19 vaccine, with macular retinal arterial occlusion noted on day 21 post-inoculation. Further work-up revealed abnormal glycemic, metabolic, inflammatory, and bleeding parameters. Vision improved from counting fingers to 20/100 at week 6 with no interventions. Conclusion: A potential association between retinal vasoocclusion and inoculation with CoronaVac in our patient is supported by the temporal sequence of events, multiple mechanisms put forward in other cases, and reports of vascular adverse reactions in large country-level trials. It is mitigated by the profound infrequency of such events and the potentially substantial risk for ocular ischemic events imparted by the patient's baseline clinical background. Continued understanding of vaccine adverse reactions, however rare, is important not only for individual patient safety. This is helpful in ensuring the utility of current vaccines and in preserving the acceptability of vaccines through and beyond the current pandemic.