Shares of Tyson Foods and other poultry processors fell on October 19, 2026, after Newcastle disease was detected at a turkey processing plant in Santa Catarina, Brazil, a major chicken-exporting region. The facility closed, and poultry movement in the area was suspended, raising investor concerns about possible global supply chain disruptions.
Tyson shares fell more than 1%. The United States imports little poultry from Brazil, but the news heightened concerns about broader poultry health risks.
Separately, a Goldman Sachs report said defensive consumer stocks such as Tyson could benefit if investors shift away from momentum stocks.