Human Myiasis Resulting from Reemergence of Cochliomyia hominivorax Screwworm, Mexico, 2025-2026.

After its elimination from Mexico in 2003, myiasis caused by New World screwworm (NWS), Cochliomyia hominivorax, has recently reemerged as a public and animal health concern. We conducted a retrospective study of human New World screwworm myiasis cases reported through Mexico's national surveillance system during April 13, 2025-March 14, 2026. Of 204 cases in official surveillance summaries, 202 had sufficient information for case-level clinical and epidemiologic analysis. Cases were concentrated in southern Mexico, particularly Chiapas, followed by Yucatán, Oaxaca, and Quintana Roo. Most (71.8%) cases occurred in men; mean patient age was 61.1 years. Lower limbs (55.0%) were the most frequently reported anatomic location, and 76.7% of patients had >1 concurrent condition. Six deaths were reported among patients with NWS myiasis; at the time of reporting, 1 death was attributed directly to NWS myiasis. Our findings support proactive clinical detection and integrated One Health surveillance along the expected northward spread of NWS.