Weekly Screwworm Status Update_2026-July-06

The U.S. outbreak has continued to grow, still concentrated in Texas plus one New Mexico dog case. The most defensible official Texas summary today is from TAHC: 12 Texas counties with cases and 23 Texas premises with cases, up from 10 counties and 18 premises at the June 29 update. (Texas Animal Health Commission)

CDC’s latest situation page, dated June 30, is now behind the animal-health dashboards: CDC still lists 16 domestically acquired U.S. animal cases as of June 26, but explicitly directs readers to screwworm.gov for the latest U.S. animal reports. CDC continues to report no locally acquired U.S. human cases. (CDC)

A non-official tracker that extracts the public USDA APHIS dashboard reported 32 U.S. animal cases, 13 counties, 2 states, 0 wild/feral cases, and 0 fly traps with detected NWS, with the latest confirmation on July 3. I would treat that as a useful dashboard extraction, but for publication I would still cite USDA/TAHC as the official source and describe this as “dashboard-derived.” (GenomicEpi.com)

Newly confirmed U.S. animal cases since June 29

Official written confirmations from TAHC

Dashboard-derived / supplemental line-list detail
The USDA-dashboard-derived GenomicEpi tracker lists additional confirmations after June 29: two Crockett County sheep on June 30 and one Crockett County sheep on July 3, plus the June 29 Pecos dog and June 29 Uvalde bovine. Because that tracker is not the official dashboard itself, I would use it for internal mapping and cross-checking, not as the sole published authority. (GenomicEpi.com)

Current U.S. status

The dashboard-derived line list currently summarizes 32 animal cases total: 31 in Texas and 1 in New Mexico, distributed across 13 counties in 2 states, with 0 wild/feral cases and 0 fly-trap detections reported in that extraction. (GenomicEpi.com)

U.S. case geography and host pattern

The dashboard-derived county burden currently lists the Texas case counties as: Crockett 9, Edwards 6, Terrell 4, Zavala 3, La Salle 2, Gillespie 1, Jim Hogg 1, Medina 1, Pecos 1, Sutton 1, Tom Green 1, and Uvalde 1; New Mexico remains Lea County 1. (GenomicEpi.com)

By host category, the same extracted line list reports: 17 cattle, 10 sheep, 3 goats, and 2 dogs. (GenomicEpi.com)

The most important new geography since June 29 is Pecos County, Texas, with a canine case, and further Crockett County sheep detections. TAHC’s Texas summary rising from 10 to 12 counties indicates two additional Texas counties were added to the official confirmed-case footprint since the prior update. (Texas Animal Health Commission)

U.S. human cases

No change: CDC says there have been no reports of locally acquired human infestations with NWS in the United States. CDC’s June 30 page also says the current risk to the public and animals in the U.S. is very low, and that risk is localized to areas where NWS cases have been reported. (CDC)

CDC still notes the earlier August 2025 travel-associated human case in a person who returned to the U.S. after travel to El Salvador. (CDC)

Mexico status and trend

The overall Mexico picture remains: widespread active disease with continuing northern-border concern, but not a simple “uniform northward surge.” The best recent secondary report citing SENASICA data says that, as of June 27, Mexico had 31,070 cumulative cases and 1,735 active cases in 27 states. It also reports active cases in northern border states: Tamaulipas 106, Nuevo León 79, and Coahuila 23. (La Jornada)

That suggests two simultaneous realities:

1. The parasite is still widely distributed in Mexico, including border states.
2. Active case burden is no longer concentrated only in the far south; several central and northern states now matter for U.S. risk.

USDA’s current-status page says Mexico’s map is updated Tuesdays/Thursdays, the list of cases within 100 miles is updated each business day, and the sterile-insect release polygon is adjusted based on science/modeling to maintain suppression and prevent spread. (APHIS)

Mexico’s sterile-fly capacity is now a major new development: a SENASICA-linked report says the Metapa de Domínguez, Chiapas plant began operation on June 28, is expected to produce 28 million sterile flies per week by mid-July, and gradually increase to 100 million per week by the end of 2026. (SENASICA)

Central America / Panama status

COPEG’s public page remains useful but appears less current than the U.S. and Mexico dashboards. The page I found is still showing epidemiological week 24, through June 20, 2026, with 561 new cases, 68,665 cumulative cases, and 34 weekly dispersal flights. (COPEG)

COPEG states that cases remain present in all Panamanian provinces except Guna Yala, and that regional cases have occurred in Costa Rica, Nicaragua, Honduras, Guatemala, El Salvador, Belize, and Mexico. (COPEG)

The species breakdown in COPEG’s week-24 data remains heavily bovine: 59,118 bovines, 3,304 canines, 2,286 swine, 1,657 equines, 1,394 sheep, 345 goats, and 326 humans, among other hosts. (COPEG)

USDA/APHIS and state control actions

USDA’s current-status page says all suspicious wounds, maggots, or infestations in animals or people should be reported immediately, and it links to the U.S. confirmed-detections dashboard. (APHIS)

USDA also says all southern ports of entry are closed to livestock trade at this time. (APHIS)

TAHC reports that federal and state partners are conducting animal and fly surveillance, epidemiological investigations, and response protocols in infested zones, while sterile-fly dispersal efforts are underway in affected areas. (Texas Animal Health Commission)

TAHC also continues its New World Screwworm Certified Inspector Program, developed with Texas A&M AgriLife, to train people in clinical identification, animal inspection, NWS treatment, and movement-certificate requirements. (Texas Animal Health Commission)

Movement restrictions

TAHC’s movement language remains important: warm-blooded animals moving outside an infested zone must contact TAHC or a NWS Certified Inspector for inspection, treatment documentation, official ID, and a movement certificate. (Texas Animal Health Commission)

TAHC’s July 1 Pecos order states that warm-blooded animals in the relevant infested zone may not move outside the zone without prior authorization, and that hides, carcasses, and animal parts capable of serving as hosts must be inspected and treated if needed before removal. (Texas Animal Health Commission)

TAHC’s July 3 Crockett-area order repeats the same movement-control structure for the modified zone including parts of Crockett, Schleicher, Sutton, Terrell, and Val Verde counties. (Texas Animal Health Commission)

Changes since June 29

The main changes are:

1. Texas official case footprint increased from 10 counties / 18 premises to 12 counties / 23 premises. (Texas Animal Health Commission)
2. Pecos County, Texas was added with a confirmed canine case detected June 30. (Texas Animal Health Commission)
3. Crockett County had additional sheep detections, including a July 3 sheep case in the official TAHC order. (Texas Animal Health Commission)
4. Uvalde County had a bovine detection on June 29, formalized in a June 30 TAHC order. (Texas Animal Health Commission)
5. CDC’s human-risk status did not worsen: no locally acquired U.S. human cases reported. (CDC)
6. Mexico’s sterile-fly production capacity changed materially, with the Chiapas plant starting operation June 28 and expected to ramp from 28 million/week by mid-July toward 100 million/week by year-end. (SENASICA)

Practical implications

For veterinarians, the case geography is no longer a narrow south Texas issue. The addition of Pecos and Uvalde, and increasing Crockett burden, means clinicians across wider areas of Texas should treat suspicious myiasis in wounds as reportable until proven otherwise.

For livestock owners, the pattern remains heavily tied to wounds in cattle, sheep, and goats. Daily inspection is especially important after calving, castration, shearing, dehorning, branding, predator injury, thorn/brush injury, tick-bite wounds, or any draining lesion.

For pet owners, the Pecos County canine case matters. Dogs are not the most common U.S. host, but the current dashboard-derived line list now shows two dog cases: one in New Mexico and one in Texas. (GenomicEpi.com)

For public health, the current U.S. message remains watchful but not alarmist: CDC says risk to people remains very low, with no locally acquired U.S. human cases. (CDC)

For entomologists, the lack of dashboard-derived wild/feral cases and lack of wild-fly trap detections, if accurate, remain important. Animal cases alone can reflect infested animals, but wild-fly detections would be stronger evidence of local fly activity. The dashboard-derived tracker reports 0 fly traps with detected NWS flies as of its July 5 extraction. (GenomicEpi.com)

Uncertainties and discrepancies

The biggest discrepancy remains case count lag. CDC’s June 30 page reports 16 U.S. animal cases as of June 26, but TAHC’s July 6 state summary reports 23 Texas premises, and the USDA-dashboard-derived tracker reports 32 animal cases as of July 3. This is best understood as a timing/data-source issue: CDC is not the current animal case dashboard. (CDC)

The second uncertainty is dashboard visibility. USDA’s official current-status page confirms the dashboard exists and describes what it captures, but the static APHIS page does not expose all row-level case data. For individual animal mapping, the dashboard itself or a faithful extraction must be checked. (APHIS)

The third uncertainty is Mexico’s real-time active-case count. I found strong recent secondary reporting citing SENASICA data through June 27, but the official SENASICA dashboard/page was not fully extractable in static text. For a formal blog post, I would manually verify Mexico’s dashboard immediately before publishing exact counts. (La Jornada)

Map generated by ChatGPT using USDA and CDC data. For full data sources, see the associated article.