The US Department of Agriculture (USDA) warned this week that four cases of salmonella may be associated with chicken salad sold at one Costco location in Lynwood, WA.The warning is specifically for those who bought the chicken salad between August 26 and September 2. However, according to the warning, the USDA and Costco are concerned that people may have frozen the salad. So, if it's hanging out in your freezer, please toss it.There hasn't been an official recall in this case yet — from Costco or the FDA. And, for right now, the worry is localized to salads sold at that one specific Lynwood store.However, if all of this feels like déjà vu, you're not imagining it. Costco recalled its chicken salads last November after they were connected to 19 cases of E. coli infection. And in October of last year, Whole Foods also recalled its chicken salad products after a routine test turned up possible listeria contamination.