Flesh-eating screwworms feast on humans in Mexico; human cases top 500
Six deaths reported among screwworm cases, one directly attributed to the flies.
The New World screwworm is not a headline from a horror script. It is a biological fact that has re-established itself in Mexico with a quiet, methodical efficiency. The numbers from the country's health ministry are stark: more than 500 human cases since the fly's return in 2024, with the pace of infestation accelerating through the most recent surveillance window.
A study in Emerging Infectious Diseases examined over 200 confirmed cases from April 2025 to March 2026. Six deaths were recorded, and at least one was directly caused by the maggots themselves. The distinction matters. In a disease outbreak, indirect mortality is common. A direct kill by the parasite is a different kind of signal.
The fly's biology is brutally simple. It lays eggs in wounds, mucous membranes, and orifices. The larvae hatch within a day and begin consuming living tissue. The mechanism is the same for humans and livestock, but the economic weight falls hardest on the cattle industry. That is where the real pressure builds.
For anyone tracking labor markets or supply chains, this is not a distant health bulletin. A screwworm outbreak in a major livestock-producing region moves through the economy in predictable ways. Quarantines, culling, and treatment costs ripple outward. The human case count is the visible symptom; the agricultural disruption is the structural consequence.
The study's finding that the infestation pace is increasing is the detail that deserves attention. It suggests the containment measures in place are not yet matching the fly's reproductive capacity. Until that gap closes, the numbers will keep climbing, and the costs will keep compounding.