In November, 2006, public health officials detected a substantial increase in reports of Salmonella Tennessee isolates. In February, 2007, a multistate, case-control study linked the consumption of either Peter Pan or Great Value Peanut Butter brands with infection. Subsequently the same strain of Salmonella Tennessee was isolated from unopened jars of peanut butter and from environmental samples collected from the processing plant. The product was recalled, and new illness reports declined. Unsanitary conditions at the Sylvester, Georgia, processing plant were known about since 2004. On April 5, 2007, ConAgra announced inadvertent moisture from a leaking roof and sprinkler system could have promoted bacteria growth in the plant. Great Value brand was sold at WalMart stores.