Texas has detected a flesh-eating parasite in livestock after 60 years
Texas officials announced they have detected the New World screwworm in livestock, the first evidence of the parasite in that state in decades.
Texas officials announced they have detected the New World screwworm in livestock, the first evidence of the parasite in that state in decades. This
Read Full Story at NPR Health →Why This Matters
The reemergence of the New World screwworm in Texas after six decades is more than a livestock health crisis—it signals a potential breakdown in regional biosecurity that could threaten both agricultural economies and public health. The parasite, which burrows into living tissue to feed, poses a direct economic threat to the state’s $20 billion cattle industry, while also raising concerns about zoonotic spillover risks into human populations.
Background Context
Once prevalent across the southern U.S., the screwworm was eradicated in the 1960s through a massive sterile male release program—a biological control strategy that remains one of the most successful pest eradication efforts in history. Its resurgence suggests either a lapse in surveillance or an environmental shift that allowed the parasite to re-establish, possibly exacerbated by climate-related factors or cross-border migration of infected wildlife.
What Happens Next
Texas will likely ramp up aerial releases of sterile male flies to disrupt breeding cycles, a tactic that proved decisive in past outbreaks. However, the delay in detection raises questions about whether funding cuts to agricultural surveillance programs have weakened early warning systems. Meanwhile, ranchers may face temporary quarantines, economic losses from infested livestock, and increased veterinary costs.
Bigger Picture
This incident reflects a growing challenge in global pest management: the erosion of eradication gains in an era of climate variability, reduced public health budgets, and increasing cross-border movement of people and animals. It also underscores the fragility of biological control systems, which rely on sustained, long-term investment to prevent resurgence.
