1. Two more Texas counties detect New World Screwworm
By Stephanie Soucheray
CIDRAP News
July 21, 2026
Two more Texas counties near the US-Mexico border have detected New World Screwworm (NWS) in animals, according to a new update yesterday from the United States Department of Agriculture. Both Schleicher and Starr counties documented the infection in sheep and cattle, respectively. The US has now detected infections from the parasitic fly in 41 animals since June 1. All but one detection has been in Texas, with a single detection recorded in New Mexico.
2. Study Validates More Trap Options to Detect New World Screwworm Flies [edited]
By Andrew Porterfield
EntomolgyToday.org
July 21, 2026
Pesticides have not been overly effective against the fly, and containment has been achieved by isolation of livestock hosts of the fly larvae and sterile insect technique (SIT), in which massive numbers of sterilized male flies are introduced into the population. Since females only breed once in their lifetimes, when they mate with sterile male flies, their eggs do not produce offspring. Historically, SIT has worked very well in controlling fly outbreaks. However, because of the very short lifecycle between egg laying and pupation, immediate identification and host animal isolation are essential.
The recent resurgence of the fly has called for better early identification of the fly, usually done through luring and trapping the insect. Recently, a research team from Uruguay and Brazil assessed the capabilities of three available fly traps: the commonly used vertical sticky trap (VST) and two versions of an Nzi trap (named for the Swahili word for "fly"). They found that all three traps worked equally well, and the Nzi traps had the advantage of preserving insect morphology for further identification. The results of their study were published last week in the Journal of Medical Entomology are included in a new, in-progress special collection of New World screwworm research in the Journal of Medical Entomology and the Journal of Economic Entomology.
Led by Pablo Parodi, Ph.D., entomologist at the Uruguay National Institute for Agricultural Research, the researchers baited all three types of traps with the commonly used fly bait Swormlure-4 and set them in four types of sampling sites (forest edge, pastures, near bodies of water, and near livestock corrals), all in northern Uruguay. The traps were set during all four seasons of the year.
In total, 96 blowflies were collected, and 15 of them were identified as C. hominivorax. Seven flies were collected by the standard Nzi trap, five by the modified Nzi trap, and three by the VST trap. The difference was not statistically significant, which means all three trap types were equally capable of trapping the screwworm fly. "One of the most notable findings was that the Nzi and Nzi-modified traps accounted for nearly 50 percent of the total C. hominivorax captures," Parodi says. "Furthermore, a significant advantage was that Nzi traps yielded well-preserved specimens, avoiding the severe morphological degradation caused by the entomological glue on the VSTs."
3. Study: Omeprazole Linked to Modest Increase in EIPH; Two Washington Horses Test Positive for EIA
Study: Omeprazole Linked to Modest Increase in EIPH
The study found no link between omeprazole and fractures or atrial fibrillation.
By Eric Mitchell
BloodHorse.com
July 20, 2026
The cumulative effects of the equine gastric ulcer treatment and preventative omeprazole has been linked to a modest increase in incidences of exercise-induced pulmonary hemorrhaging, according to study published this month in the Journal of the American Veterinary Medical Association.
"Cumulative omeprazole dose in the preceding 30 days was associated with an increased hazard of EIPH detection," stated the discussion of the study reviewing Hong Kong race records from two different seasons. "Although the estimated strength of the association was not strong, the estimated population attributable fraction of approximately 11% suggests that a modest proportion of the EIPH incidence rate may be attributable to omeprazole exposure under a causal interpretation.
Annapolis
"Clinically effective omeprazole doses for equine gastric ulcer syndrome vary according to lesion type and treatment conditions, as well as the formulation. In Thoroughbred racehorses, doses as low as 1 mg/kg once daily of enteric-coated omeprazole have been reported to be as effective as 4 mg/kg once daily for treatment of squamous ulceration when administered before exercise after a brief fast," the discussion continued, noting that in this study the average daily dose was approximately 2 mg/kg/day in a horse weighing 480-500 kilograms (1,060-1,100 pounds).
"However, these data do not identify a cumulative dose threshold that can be considered free of EIPH risk," the discussion stated.
Two Washington Horses Test Positive for EIA
EDCC Health Watch
TheHorse.com
July 20, 2026
Two horses at a private facility in Okanogan County, Washington, recently tested positive for equine infectious anemia (EIA). All 18 horses at the facility were tested for EIA and piroplasmosis due to an epidemiological link to an EIA-positive facility in Pierce County, Washington. The two positive horses were euthanized, and the other 16 horses will remain under quarantine until their 60-day retest.
Full text: https://thehorse.com/1146104/2-washington-horses-test-positive-for-eia/
4. Swine Respiratory Disease susceptibility surveillance: Advancing stewardship and health outcomes [webinar]
National Hog Farmer
July 16, 2026
Good stewardship starts with smart choices. That's especially important when it comes to selecting the right antibiotic treatment for swine respiratory disease. Get the latest update on antimicrobial susceptibility surveillance trends and understand how 20+ years of monitoring is strengthening our understanding of responsible antibiotic use across the industry. The webinar will also reinforce best practices that promote responsible use principles and improve health outcomes.
Date: Aug 20, 2026 Time: 12:00 pm CDT Duration: 1 Hr
Access webinar at this link:
https://www.nationalhogfarmer.com/livestock-management/swine-respiratory-disease-susceptibility-surveillance-advancing-stewardship-and-health-outcomes
5. Screwworms: Rep. Harder Announces New Bill to Protect Valley Livestock from Flesh-Eating Maggots [edited]
Harder Press Release
ContraCostaNews.com
July 18, 2026
STOCKTON - Today, Rep. Josh Harder (CA-09) announced new bipartisan legislation to protect Valley livestock and agriculture communities from a growing outbreak of flesh-eating insects. Harder's Protecting America's Herds Act invests in early detection and prevention of New World Screwworm flies to control the outbreak and ultimately keep these parasites out of the [California Central] Valley.
How Harder's bipartisan bill gets the screwworm outbreak under control:
Early Detection and Prevention - Deploys inspectors and trains producers on identification, treatment, prevention, and case reporting.
Priority Risk Funding - Fast-tracks funding to the states and communities at the highest risk of screwworm introduction or spread.
Interagency Coordination - Enhanced coordination with U.S. Department of Agriculture, Animal and Plant Health Inspection Service, veterinarians, and state animal health officials.
The Protecting America's Herds Act is endorsed by the National Cattlemen's Beef Association, the Public Lands Council, and the American Sheep Industry.
6. Recordings Available: FMD Vaccination and SMS, SBS Plan Updates
Preventalytics
July 21, 2026
If you missed the webinars, the recordings are now available on the USDA VS NTEP NADPRP YouTube channel. Thanks for your interest!
"What U.S. Livestock Producers Need to Know About FMD Vaccine" (63 mins) from July 1: https://youtu.be/odCKJJZY36g
Presenters:
Danelle Bickett-Weddle, DVM, MPH, PhD, DACVPM; Preventalytics, LLC and Consultant to National Milk Producers Federation (NMPF)
Jennifer Steele, DVM, PhD; Manager of the North American FMD Vaccine Bank (NAFMDVB) and the National Animal Vaccines and Veterinary Countermeasures Bank (NAVVCB), USDA APHIS VS
Justin Smith, DVM; Kansas Department of Agriculture Animal Health Commissioner
"SMS Plan, SBS Plan, Websites, Resource Updates" (45 mins) from June 25: https://youtu.be/cksHZYEpIC8
Presenters:
Miquela Hanselman, MPH, Senior Director of Regulatory Affairs, National Milk Producers Federation (NMPF) - Part 1
Danelle Bickett-Weddle, DVM, MPH, PhD, DACVPM; Preventalytics, LLC and Consultant to National Milk Producers Federation (NMPF) - Part 1
Julia Herman, DVM, MS DACVPM, Beef Cattle Specialist Veterinarian, National Cattlemen's Beef Association - Part 2