( CNN ) A sweet treat has turned potentially deadly for dozens of people in multiple states . At least seven people have died after eating caramel apples that may have been infected with Listeria monocytogenes . Some 32 people have become infected with the deadly bacterium in 11 states , according to the Centers for Disease Control and Prevention . Of those people who got sick 31 were hospitalized and seven deaths have been reported . A press release from the Centers for Disease Control and Prevention says that `` listeriosis contributed to at least three of these deaths . '' The Public Health Agency of Canada has also identified two cases of listeriosis in Canada and the samples show the same DNA fingerprints as the American cases . Listeria What you need to know . Of the people who have gotten sick , 10 were pregnant . Pregnant women are 10 times more likely to get listeriosis after eating infected food . Of the rest of the cases , three were children who were otherwise healthy , the CDC said . Symptoms of listeriosis infection include muscle aches , headache , stiff neck , confusion , loss of balance , fever and convulsions . Typically , symptoms begin three to 70 days after eating the tainted food . To date 23 of the 26 people who were interviewed about their illnesses remembered eating commercially produced , prepackaged caramel apples before they got sick . Most of the people who got sick with this outbreak saw the doctor in late October and November . Investigators are still trying to determine all the contributing factors in the case . To date caramel apple brands named in interviews include Happy Apple , Carnival and Merb 's Candies . Investigators are also looking at other companies for the source of the contamination . In the meantime , the CDC is warning consumers who may have bought caramel apples with toppings like nuts , chocolate or sprinkles not to eat them , at least not until investigators figure out the source of the contamination . Three companies -- Happy Apple Company of Washington , Missouri ; California Snack Foods , of El Monte , California ; and Merb 's Candies of St. Louis , Missouri -- have issued voluntary recalls of their caramel apples . The companies have used apples from Bidart Bros . The FDA traced the distribution of the apples eaten by eight people who got sick in the outbreak . Bidart Bros. is the only apple grower that supplied both Happy Apple Company and Merb 's Candies . On December 22 , Bidart Bros. recalled Granny Smith apples it sold in 2014 to caramel apple companies . Lab results for Listeria monocytogenes done in a joint inspection of the firm by the FDA and the California Department of Public Health turned up positive . Lab tests are ongoing . On January 6 , Bidart Bros. expanded its voluntary recall to include Gala apples shipped from the company 's Shafter , California , packing facility in 2014 . There are about 1,600 cases of listeriosis reported in the United States every year . This kind of infection kills about 260 people annually , according to the CDC .
7 people have died after eating caramel apples possibly infected with listeria . 32 people have become infected in 11 states ; listeriosis is on the CDC notifiable diseases list . Comment: