Of cattle and humans: A narrative review on the re-emergence of the New World screwworm (Cochliomyia hominivorax) and its threat to human health.

Following more than two decades of successful elimination of the New World screwworm fly from Central and North America, new outbreaks emerged in Panama in 2023, initially affecting livestock, and rapidly spreading northward to impact not only livestock but also companion animals and humans. Forest degradation, increasing cattle density, and climate-driven shifts in the fly's distribution-particularly its recolonization of regions it historically occupied-are converging to expose critical gaps in preparedness and cross-sector coordination. In this review, we examine the drivers of screwworm re‑emergence and present current clinical and epidemiological evidence of human infection, highlighting ongoing barriers to detection and response. Building on lessons from recent zoonotic health emergencies, we propose actionable One Health recommendations aimed at tackling the re-emergence of screwworm. An effective response will require sustained political commitment and coordinated cross-border collaboration to prevent further spread, protect vulnerable populations, and ensure that this myiasis is prioritized, ending the neglect of this tropical disease.