Mexico: New World screwworm cases up 53% in one month

Cases of New World Screwworm (NWS) continue to rise in Mexico. According to government data cited by Reuters, as of August 17, 5,086 infestations in animals had been recorded, representing a 53% increase compared to July. Of that total, 649 remained active.

“This is absolutely concerning. Having a 50% increase from one month to the next, especially in the middle of extreme heat, means they still haven’t managed to control the situation,” said Neal Wilkins, CEO of the East Foundation.

The National Cattlemen’s Beef Association (NCBA) warned that “the increase in cases in Mexico shows that New World Screwworm remains a very present threat. We must move forward with all possible prevention and mitigation tools, including the announced funding for a domestic sterile fly unit and strengthened monitoring and control measures.”

The surge in cases appears to be linked to increased inspection by ranchers and the reporting of any wounds or suspicious signs of infestation. Most reports involve cattle (85%), but infestations were also detected in dogs (6%), pigs (3%), horses (3%), and sheep (2%), according to official data and the Panama–US Commission for the Eradication and Prevention of Screwworm in Animals (COPEG).

In July, Mexico’s National Service for Agri-Food Health, Safety and Quality (Senasica) confirmed a case in Ixhuatlán de Madero, Veracruz, about 600 km from the US border. This finding came two months after detections in Oaxaca and Veracruz, less than 1,100 km from the northern limit.