With the first U.S. case of flesh-eating screwworm infection in Maryland, Americans now face a biosecurity threat that exposes dangerous gaps in border health surveillance.

Story Highlights

• A rare human case of myiasis from New World screwworm is confirmed in Maryland after travel to Central America during an ongoing regional outbreak.
• The Central American screwworm outbreak is devastating livestock, threatening food security, and showing signs of cross-border spread.
• Experts warn that lapses in surveillance and porous borders heighten zoonotic risks to both humans and U.S. agriculture.
• Renewed scrutiny falls on government biosecurity, eradication efforts, and the need to protect American farmers and public health.

Rare Human Infection Raises Alarm Amid Regional Livestock Crisis

Health authorities have confirmed that a Maryland resident contracted myiasis—an infection caused by flesh-eating screwworm larvae—after returning from Central America. This marks the first U.S. human case in decades and comes as a severe screwworm outbreak continues to ravage livestock throughout Central America and Mexico. The introduction of this parasite into the U.S. not only threatens individual health but could have catastrophic implications for the nation’s cattle industry if not contained rapidly.

The patient with the first human infestation of travel-associated New World screwworm in the United States has recovered from the flesh-eating parasite, and there was no sign of transmission to other people or animals, the Maryland Department of Health said on Monday.… pic.twitter.com/SfVRghzlqP

— Yahoo News (@YahooNews) August 26, 2025

The New World screwworm, a parasitic fly native to the Americas, was once eradicated from the U.S. through aggressive sterile insect campaigns and vigilant surveillance. However, recent lapses in oversight—possibly worsened by climate change and increased movement of people and animals—have allowed the pest to re-emerge in Central America and southern Mexico. These regions, with their extensive but under-resourced livestock sectors, are now experiencing significant animal deaths and economic hardship.

Watch: Rare human New World screwworm case confirmed in Maryland

Cross-Border Spread: Risks to U.S. Agriculture and Public Health

Authorities are especially concerned about how easily zoonotic threats like screwworm can cross borders, particularly in an era of global travel and trade. The infection risk is no longer confined to livestock; it now directly threatens Americans who travel or live near affected zones. While the immediate case was linked to travel, sustained outbreaks abroad increase the likelihood of accidental reintroduction via animals, travelers, or even illegal crossings. Such scenarios could devastate rural communities and force costly government eradication campaigns, all while testing the limits of the nation’s public health infrastructure.

Government agencies such as the CDC and the Pan American Health Organization have issued alerts to clinicians and veterinarians, urging heightened surveillance and rapid reporting of suspected cases. In response, containment and eradication programs are being reinforced, but critics warn that years of bureaucratic complacency and underfunding have left America exposed.

The Path Forward: American Resilience Tested

The rarity and seriousness of human myiasis demand prompt medical attention and public education. The current outbreak has exposed critical weaknesses in surveillance, animal health systems, and policy coordination—weaknesses that, if left unaddressed, could erode confidence in America’s ability to defend its borders and protect its citizens. This case is a stark reminder that biosecurity is inseparable from national security, requiring vigilance, common sense, and unwavering defense of the American way of life.

As containment efforts intensify, the screwworm episode serves as a warning: threats to American health and industry can arise swiftly from beyond our borders, and only through steadfast commitment to robust surveillance and rural resilience can the nation remain secure. With the stakes clear, policymakers face renewed pressure to close loopholes that invite biosecurity lapses, ensuring that American agriculture and public health are never again left vulnerable to preventable foreign threats.

Sources:

CDC: Clinical overview and outbreak updates
ABC News: Human case detection and outbreak context