Clinical Insights and Case Analysis of Disorders Attributed to Cicadas in the Emergency Department

In 2024 the United States experienced a rare co-emergence of two periodical cicada broods (XIII and XIX), along with annual cicadas. Although not inherently dangerous, cicadas have been linked to allergic reactions and unintentional injuries. The public health impact of this extraordinary event is poorly understood. In this study we aimed to characterize emergency department (ED) and urgent care (UC) visits associated with the 2024 cicada emergence.

We conducted a retrospective chart review across ED and UC sites in a large healthcare system in the Midwest and Southeast that coincides with the ranges of the periodical cicada broods, from April 1-July 31, 2024. Electronic health records were searched for "cicada" and common variants. Two emergency physicians in each region reviewed identified records. Data extracted included demographics, diagnoses, visit characteristics, diagnostics, treatments, and outcomes.

Of 1,304,743 total visits, 68 mentioned "cicada" or a variant; 42 were confirmed as cicada related. Patient ages ranged from 7 weeks to 87 years of age (median 38 years). Trauma was the most common cicada-related presentation (33), followed by falls (21), blunt trauma (6), vehicular/bicycle accidents (3), and other mechanisms. Additional cases involved allergic reactions (3), environmental exposure (2), and neurologic symptoms (2). Imaging was common: 57% had radiographs and 43% computed tomography. Seven patients sustained fractures; one required laceration repair, and six were admitted.

While the overall health system impact was limited, cicada-related visits revealed important patterns of injury. Findings support the need for public education and preparedness during future mass insect events.