In May 2025, CDC announced an investigation of Salmonella infections associated with backyard poultry. As of May 19, 2025, a total of 104 people who were infected have been reported from 35 states. Illnesses started on dates ranging from February 9, 2025, to May 3, 2025. Of 83 people with information available, 25 (30%) have been hospitalized. One death has been reported from Illinois. Salmonella Mbandaka or Salmonella Enteritidis were detected in case-patients.

Investigators in Ohio collected samples from the inside of boxes used to ship poultry from hatcheries to retail stores, including the box liner and bedding. WGS showed that the Salmonella Mbandaka found in these samples was the same strain as the one found in sick people. This sample was linked to a hatchery that was also identified by traceback data.

Based on WGS analysis, bacteria from 67 people's samples and one environmental sample had no predicted resistance; two people's samples predicted resistance to gentamicin, streptomycin, and tetracycline, while 35 people's samples predicted nonsusceptibility to ciprofloxacin.