The Centers for Disease Control and Prevention has activated a Level 3 emergency response for the New World screwworm following recent detections of the destructive parasite in livestock and other animals in southern Texas and a county in New Mexico.
A Level 3 response is the lowest tier in the CDC’s emergency response framework, the agency said in a statement.
Advertisement
Federal health officials are working alongside the U.S. Department of Agriculture and state authorities to contain the outbreak.
The declaration is an example of the Trump administration’s whole-of-government approach, Agriculture Secretary Brooke Rollins said Thursday.
“The CDC is just one more step in the right direction that allows us to deploy more resources at the federal level,” Rollins told reporters in Texas.
The USDA is tracking confirmed animal infestations through a public dashboard as officials monitor the spread of the pest.
New World screwworm primarily threatens livestock, pets, and wildlife. The parasite develops when screwworm flies lay eggs in open wounds or body openings, allowing larvae to feed on living tissue.
Advertisement
While human infections are possible, no cases have been reported in the United States, and federal officials continue to assess the risk to the public as low.
Health officials emphasized that New World screwworm is not contagious and cannot spread directly between animals, from animals to humans, or from person to person.
Instead, infections occur only through exposure to screwworm flies in affected areas, noted the CDC.
The Trump administration has been preparing for the threat for more than a year. In 2025, the USDA launched an aggressive strategy to prevent the parasite from reestablishing itself in the United States, said the agency.
The effort is being coordinated through an interagency working group led by the USDA, CDC, and Department of the Interior as part of a broader One Health initiative that recognizes the connection between human, animal, and environmental health.
The CDC has activated a Level 3 emergency response for the New World screwworm.
ABC’s Youri Benadjaoud has the details. pic.twitter.com/unXFQm7mDN
— ABC News (@ABC) June 13, 2026
Officials noted that the United States successfully eradicated New World screwworm decades ago and expressed confidence that the parasite can be eliminated again through coordinated surveillance and response efforts.
The CDC is urging healthcare providers in affected areas to remain alert for possible human cases and report any suspected infestations to state or local health authorities.
Veterinarians are also being encouraged to immediately report suspicious animal cases to state animal health officials and the USDA.
The screwworm was first eradicated in the 1960s, but it has come back before, The Hill reported.
The most recent U.S. outbreak of New World screwworm occurred in Florida between 2016 and 2017.
According to the CDC, a coordinated response involving federal, state, and local agencies successfully eradicated the parasite before it could become permanently reestablished in the country.
Health officials point to that effort as evidence that aggressive containment and eradication measures can be effective when agencies work together quickly to identify and eliminate infestations, the CDC noted.
While the United States remains free of established New World screwworm populations, the parasite continues to be endemic in several countries, including Cuba, Haiti, the Dominican Republic, and parts of South America.
Its continued presence in the Western Hemisphere has kept federal animal and public health officials on alert, particularly as increased travel and cross-border animal movement create opportunities for the pest to spread into previously unaffected areas, notes The Hill.
“New World screwworm (NWS) is a serious pest of livestock and wildlife,” the USDA noted on its website.
“USDA is leading a coordinated One Health response to combat NWS. This is not a food safety issue—the U.S. food supply remains safe,” the agency noted further.
“The current risk to animals and people in the United States is very low,” it said.
This article may contain commentary which reflects the author’s opinion.
