New World Screwworms Trigger Quarantines in Four Texas Counties

A deadly infestation of New World Screwworms has crossed the US border, triggering quarantines in multiple Texas counties.

The Texas Animal Health Commission issued orders for La Salle, Uvalde, Webb, and Zavala Counties following the spread of these flies over the last week.

Officials confirmed four cases among local livestock in Texas, alongside a separate case involving a dog in New Mexico announced on Monday.

New World Screwworms are flies that deposit hundreds of larvae directly into animal or human wounds.

These larvae hatch within hours and immediately begin consuming the victim's flesh, causing deep, painful injuries.

Without prompt treatment, these infestations often lead to severe infection and death.

The four affected counties in Texas serve over 300,000 residents and lie less than 100 miles from San Antonio.

San Antonio's greater metropolitan area is home to nearly three million people, placing a large population at risk.

The current quarantine strictly restricts the movement of all warm-blooded animals out of the designated zones.

Restricted animals include cattle, horses, goats, dogs, and other wildlife.

Residents within the zones are not restricted from leaving, though they can carry the infestation.

The Centers for Disease Control and Prevention reports more than 2,100 human infections with screwworms in Mexico and Central America this year.

This is a developing story with more details expected to emerge soon.

The US Department of Agriculture has confirmed the presence of New World Screwworms in both New Mexico and Texas.

While the quarantine stands, animals cannot leave the zone without specific permission from the Texas Animal Health Commission.

Owners must contact TAHC for an inspection before transporting livestock or pets elsewhere.

If approved, officials issue a movement certificate after checking the animals for any signs of screwworms.

The primary goal is to protect livestock, pets, and people from a potential widespread outbreak.

Such an outbreak could devastate the US meat supply in the South and potentially jump to humans.

No cases of screwworms have been found in people within the United States so far.

As of June 8, over 185,000 cases of these parasite infestations have been discovered in Mexico and Central America.

The US Department of Agriculture stated the situation is evolving and new information will emerge as investigations continue.

Officials are working closely with partners in New Mexico, Texas, and the broader region to identify and contain cases swiftly.

To protect yourself in areas where New World screwworm flies are present, the CDC recommends keeping any open wounds clean and covered.

Texas officials have ordered a strict animal quarantine across four counties. The goal is to stop deadly parasites from spreading throughout the South.

Farmers must wear loose long sleeves, pants, hats, and socks. This gear minimizes exposed skin and reduces infection risk.

Early signs of a screwworm infection include painful sores that refuse to heal. Victims may notice a foul smell, bleeding, or moving maggots near wounds, noses, mouths, eyes, or ears.

Livestock in the region faces high danger. These parasites crossed the border from Mexico. Untreated victims can die quickly.

Officials in Mexico found cases last year in Chiapas, Oaxaca, and Veracruz. These areas lie along a major migrant caravan route used for over a decade.

Researchers feared stopping the flies at the US-Mexico border might be impossible. Rising temperatures could allow infestations within two decades.

Gulf states like Texas, Florida, and Louisiana are at risk. Data suggests cattle and people could face attacks by 2055.

Before last week, New World Screwworm cases vanished from Texas sixty years ago.

The pests became a major issue in the early 1900s. Infected livestock caused roughly $1.8 billion in losses today.

Scientists eradicated the species by 1982 using a clever biological method. They sterilized male flies with radioactive gamma rays. This prevented them from breeding with females.

Female flies can lay over 300 eggs in open wounds. The eggs hatch within 24 hours. The larvae then eat the victim's living tissue.

The Texas Animal Health Commission noted a sharp rise in Central America since 2023. The spread covers Belize, Costa Rica, El Salvador, Guatemala, Honduras, and Nicaragua.

In November 2024, officials detected the parasite in a cow at a Chiapas checkpoint. Progressive northern spread in Mexico has been confirmed since that discovery.