Seasonal and Environmental Variations in Endophthalmitis after Intravitreal Anti-vascular Endothelial Growth Factor Injection: A Six-year Review.

To evaluate seasonal and environmental variations on the incidence and outcomes of postinjection endophthalmitis. A single-center, retrospective cohort study was conducted including all patients diagnosed with post-injection endophthalmitis between 2013-2018. Associations between climate variables and endophthalmitis incidence were evaluated. Of 423,297 injections administered, seasonal distribution in spring, summer, autumn, and winter was 26%, 27%, 25%, and 22%, respectively. Of 171 cases of endophthalmitis identified, seasonal distribution over the spring, summer, autumn, and fall was 25%, 23%, 26%, and 26%, respectively. Endophthalmitis incidence was not correlated with monthly precipitation ( In contrast to previous work on postcataract endophthalmitis, seasonal and weather factors were not associated with post-injection endophthalmitis risk or bacterial species isolated. Visual outcomes at initial endophthalmitis presentation were correlated with precipitation, and worse visual outcomes were seen in patients who developed endophthalmitis in the spring.