A recent study of ground beef-related Salmonella outbreaks found higher levels of infection among more socioeconomically vulnerable individuals.

For the study, the researchers analyzed data from the U.S. Centers for Disease Control and Prevention’s (CDC’s) Foodborne Disease Outbreak Surveillance System (FDOSS) for patients with laboratory-confirmed Salmonella infections in ground beef-associated outbreaks that occurred between 2012 and 2019. This case patient data was compared against a control dataset from CDC’s FoodNet Population Survey for 2018–2019. The FoodNet Population Survey is a periodic survey of randomly selected residents in the FoodNet surveillance area (a regionally diverse geographic area that includes approximately 15 percent of the U.S. population) that aims to estimate the disease burden from acute diarrheal illness and the frequency of exposures linked to diarrheal illness.

The researchers considered CDC’s/the U.S. Agency for Toxic Substances and Disease Registry’s (ATSDR’s) Social Vulnerability Index (SVI) when analyzing patient data.

Among case patients, the researchers found increased county-level social vulnerability and socioeconomic vulnerability to be associated with infection by Salmonella in outbreaks linked to ground beef. Case patient status was not strongly associated with the other SVI themes of household composition and disability, minority status and language, and housing type and transportation. After adjusting for other SVI themes and demographic characteristics, the odds of being linked to a ground beef-associated outbreak increased by 24 percent.

The findings help identify possible health inequities in Salmonella infections among people who eat ground beef and suggest that community-level factors like socioeconomic status are associated with increased risk of illness. Analyzing community-level social factors using tools like CDC’s/ATSDR’s SVI can help characterize underlying social determinants of illness risk among people linked to outbreaks.