Screwworm tally in United States reaches 31

Graphic and headline:  Texas Public Radio, 7/3/2026

The most recent Texas detections were two infestations in sheep in Crockett County, both confirmed June 30. 

This tracker is updated as new infestations are confirmed. Continue reading for answers to common questions about the New World screwworm, including how infestations begin, which animals are at risk and what Texans should know. 

What is the New World screwworm? 

Despite its name, the New World screwworm isn't a worm. It is the larval stage of the fly (Cochliomyia hominivorax), a parasite that feeds on the living tissue of warm-blooded animals. 

Infestations begin when an adult female screwworm fly lays eggs in an open wound or natural body opening. Within hours, the eggs hatch and the larvae begin feeding on living tissue, unlike common maggots, which feed on dead or decaying tissue. 

As the larvae burrow deeper into tissue, wounds become larger and often infected. Without treatment, infestations can be fatal.

Related posts:

June 16-30, 2026

Contemplating the spread of screwworm in the United States.  (6/22)

Eradication of screwworm becomes undone during Trump regime of sycophantic cabinet secretaries like Brooke Rollins @USDA.  (6/17)

Falling down on the job:  Brooke Rollins creates a disaster zone @USDA.  (6/16)\

June 1-15, 2026

Apparently, incompetent Agriculture Secretary Brooke Rollins spends too much time posing with chickens.  (6/15)
Donald Trump fumbles the ball in the effort to halt the spread of screwworm.  (6/14)

Screwworm update from The Texas Tribune.  (6/13)

Screwworm spreads in Texas while Trump fiddles and Brooke Rollins poses.  (6/8)

Texas screwworm:  Disaster in the office of Secretary of Agriculture Brooke Rollins.  (6/6)

Screwworm  has arrived in United States under the unwatchful eyes of Donald Trump and Brooke Rollins.  (6/8)

Jan-May 2026

Not suitable for reading on a full stomach.  (5/7)

New World Screwworm hitchhikes its way to the U.S.-Mexico border.  (4/29)

The fact that experts have to tell ranchers report, don't hide it is probably not a good sign.  (4/29)

Screwworm detected in Mexico less than 50 miles from United States border.  (1/21)

2025

New World screwworm:  Next stop, Laredo Texas.  (9/28)

New World screwworm double vision.  (8/8)

New World screwworm, not yet in United States, is already screwing us at the meat counter.  (7/31)

Are we ready for the New World screwworm?  (7/30)

In the news:  New World Screwworm.  (5/13)