Livestock, Reuters Mexico hopes to quickly resolve New World Screwworm case halting cattle exports into US By Geralyn Wichers, Lizbeth Diaz, Sarah Morland November 28, 2024 Reading Time: < 1 minute Mexican President Claudia Sheinbaum said that Mexican and U.S. officials were in contact over a case of New World screwworm (NWS) detected late last week that caused the U.S. to halt imports of Mexican cattle.