Flesh-eating screwworm cases exceed 500 in Mexico
Deadly parasite's spread among humans is accelerating
1Reemergence of the parasite
The New World screwworm (NWS) fly reappeared in Mexico in 2024. This parasite was once endemic in both Mexico and the US. The flies lay hundreds of eggs in wounds, inflamed tissues, and mucous membranes of warm-blooded animals. The resulting maggots hatch within a day and begin feeding on living flesh.
2Rising case numbers
According to Mexico's Ministry of Health July 2025 report, human cases have surpassed 500. A study published in Emerging Infectious Diseases analyzed over 200 confirmed cases between April 2025 and March 2026. The research revealed an increasing infestation rate. Six deaths were reported among the 200 cases studied.
3Lethal effects
Researchers confirmed at least one death was directly caused by fly larvae. The maggots create horrific, life-threatening wounds in various warm-blooded species, including humans. However, they're particularly devastating to livestock, causing significant agricultural losses.
4Transmission method
The parasite spreads by laying eggs in open wounds and mucous membranes. The eggs quickly develop into larvae that consume living tissue. This process causes severe pain and life-threatening infections in affected individuals, requiring immediate medical attention.
5Historical context
The New World screwworm was largely controlled during the 20th century. Its recent reemergence has alarmed health authorities. Experts link the resurgence to climate change and relaxation of control measures. The situation recalls historical outbreaks that required massive eradication efforts.
6Public health risk
The accelerating infection rate poses a serious public health threat. Rural communities and veterinarians face particularly high risks. Mexican authorities are preparing emergency response plans, but resource limitations complicate containment efforts. Preventive education campaigns are underway.
7Economic impacts
The parasite causes significant losses in livestock industries. Treatment costs for infected animals are high and often ineffective. Farmers frequently must cull affected animals, compounding economic damages. The agricultural sector fears long-term productivity declines.
8Global concerns
Experts worry about cross-border spread, particularly to southern US states. International cooperation and enhanced border controls are considered critical for containment. The situation highlights vulnerabilities in global health surveillance systems against resurgent tropical diseases.
Original article: Ars Technica - All content — Meksika'da et yiyen kurtçuk vakaları 500'ü aştı