Mexico's Cattle Worm Outbreak Reaches 77 Cases in Chihuahua, 644 in Guanajuato

The cattle worm (Gusano Barrenador del Ganado) outbreak in Mexico has expanded to 77 confirmed cases in the state of Chihuahua as of 4 August, affecting 23 municipalities. The most affected municipalities are Coronado (16 cases) and Matamoros (9 cases). Authorities have released roughly 10 million sterile flies to curb the parasite by mating with wild females, preventing further reproduction. Federal, state and municipal protocols for prevention, surveillance and eradication remain active, including livestock inspections and wound reporting.

In the central state of Guanajuato, a total of 644 cases have been recorded since the start of the national outbreak, with 100 cases currently active. The municipalities with the highest active counts are Xichú (25), San Diego de la Unión (19) and San Luis de la Paz (14). Nationwide, SENASICA reports 36,348 cumulative cases and 1,905 active cases across species, the majority in bovines. Ongoing measures include continued sterile‑fly releases and heightened epidemiological monitoring to prevent further spread.