Panama City
Capital and largest city of Panama.
Panama City, the capital of Panama, is home to the COPEG plant at Pacora, which was the region's only producer of sterile New World screwworm flies until a second plant opened in Mexico in June 2026.
Last refreshed: 4 October 2026
Timeline for Panama City
Mentioned in: Screwworm cases in Mexico rise fivefold
Pandemics and BiosecurityBackground
Panama City is the capital and largest city of Panama. East of it, at Pacora, stands the sterile-fly plant run by COPEG, the Panama-United States Commission for the Eradication and Prevention of screwworm. The plant opened in 2006 and can generate more than 100 million pupae a week, according to the US Department of Agriculture.
Pacora was the region's only producer of sterile screwworm flies until a second plant opened at Metapa, in Chiapas, Mexico, in June 2026. Its flies held a barrier zone at Panama's Darién Gap from 2006, and the breach of that barrier in 2023 opened the parasite's current spread north.
On one expert view, sterile-fly supply, not human medical care, is the binding constraint on that spread. Mexico recorded 575 human screwworm cases in 2026 to 18 September, five times its total for 2025.