In addition to raw jalapeño peppers, avoid eating raw serrano peppers from Mexico, warns the FDA. According to Associate Commissioner of Foods David Acheson, a key breakthrough has occurred. A serrano pepper sample and a water sample from a farm in Nuevo Leon, Mexico, which is in the northeastern state of Nuevo Leon partially bordering Texas, tested positive for the Saintpaul strain of salmonella. It was linked through the supply chain with a single contaminated jalapeño pepper found in a distribution center in McAllen, Texas. Both peppers and tomatoes, originally thought to be the source of the outbreak, are grown on the farm. The U.S. Centers for Disease Control and Prevention originally blamed tomatoes, but the number of cases kept climbing despite a warning to consumers in June to avoid eating certain types of raw tomatoes. On Wednesday, Dr. Acheson confirmed all tomatoes currently on the U.S. market are safe to eat. A Mexican Embassy spokesman in Washington wrote that Mexico has suspended exports of produce from the company as a precautionary measure, while the investigation by Mexico and the U.S. continues. Asked if the FDA is focusing on one company, spokeswoman Stephanie Kwisnek said the agency is looking at the "distribution chain, from production to consumption. We go where the science leads us." The outbreak, the largest food-borne outbreak in at least a decade, began in April, and more than 1,300 cases have been confirmed in the U.S. and Canada. In addition to the jalapeño pepper found in Texas, another contaminated jalapeño was found this week in a Colorado home, where one of the residents had been sickened with the Saintpaul strain.