Enlarge / Red onions have been fingered as the likely culprit. (credit: Getty | Thomas Trutschel) An outbreak of Salmonella infections linked to tainted onions has mushroomed in North America. So far, the outbreak has sickened 879 people, hospitalizing 114 across 43 US states and seven Canadian provinces. The US Food and Drug Administration traced the outbreak back to red onions produced by Thomson International Inc.