Pet jerky treats, mostly imported from China, are being linked to more than 1,000 deaths in dogs, more than 4,800 complaints about animal illness, and, for the first time, sickness in three people who ate the products, federal health officials said Friday, according to nbcnews.com. But Food and Drug Administration officials say they still can't identify a specific cause for the reported illnesses or deaths, despite seven years of tests and investigation.