Officials from the US and Mexico signed a cooperative agreement on Tuesday in a bid to combat the spread of food-borne bacteria across the border between the countries. The agreement was signed by the Secretary of the US Department of Health and Human Services, Tommy Thompson, US Department of Agriculture (USDA) under-secretary William T. Hawks, the Mexican Secretary of Health, Dr Julio Frenk, and Javier Trujillo, director-in-chief of Mexico's National Service for Protection, Food Safety and Quality of Agricultural Products.