While SIT programs effectively pushed NWS populations southward from the United States to Mexico and, finally, to a buffer region at the border between Panama and Colombia, there has been an alarming resurgence of the NWS northward into Central America and southern Mexico, beginning in 2022. On June 3rd, 2026, the first NWS case in Texas (USA) in 60 years was identified from a bovine calf, and as of July 1st, the number of confirmed cases in Texas has risen to 30 with detections in cattle, goats, and sheep, spanning eight counties and extending 150 miles due north from the Texas-Mexico border at Laredo.
At the peak of the SIT program to eradicate NWS (1950s –1980s), seminal research was conducted to define NWS biology and ecology, much of which was published in ESA journals. This special collection, “Re-invasion of the New World Screwworm in Central and North America,” is being presented jointly by the Journal of Medical Entomology and the Journal of Economic Entomology to feature reviews and research that intend to address the challenges of re-eradicating NWS. Are there new techniques and technologies available that can advance eradication strategies or ensure that SIT remains successful? Are there updated tools for assessing risks given the differences in landscape and climate since NWS was last in Central and North America? What strategies can we adopt from South American countries where NWS is endemic? Most importantly, what knowledge gaps still exist that require exploration to refine eradication approaches? It is our hope that this collection will spark opportunities for our scientific community to collectively address the threat of NWS to companion animals, livestock, and wildlife.
All the papers in the collection are freely available to read and download. This page will continually be updated as more papers are accepted and published.
Featured photo courtesy of Dr. Sohath Zamira Yusseff-Vanegas.
Re-invasion of the New World Screwworm in Central and North America: Past Experiences and Moving Forward
Other Recently Published Papers in the ESA Journals: