The outbreak began with a July recall of 7 million pounds of meat

A 10th person has died after eating Boar's Head deli meat tainted with listeria, according to an update by the Centers for Disease Control and Prevention (CDC). Fifty-nine others got so sick they had to be hospitalized.

The CDC said the latest victim was from New York. Boar's Head Provisions issued a recall in July for 7 million pounds of deli meat it said could be contaminated with listeria.

Though the recall was issued two months ago, the CDC expressed concern that some of the listeria-tainted products could still pose a threat. The agency notes that some of the meat has a "sell-by" date that extends into October. It also notes that listeria symptoms might not appear for 10 weeks after exposure.

"Everyone should check their homes for any remaining recalled Boar's Head products since they can have long a shelf-life," the CDC said in an update. "Look for 'EST. 12612' or 'P-12612' inside the USDA mark of inspection on the product labels."

The CDC said the listeria outbreak linked to deli meat is the largest since the 2011 outbreak linked to tainted cantaloupe.

The source of the outbreak

The source of the current outbreak was not hard to find. It was traced to a Boar's Head processing plant in Virginia that the Food Safety and Inspection Service (FSIS) had cited multiple times for unsanitary conditions.

FSIS inspectors reported 69 cases of noncompliance at the plant over the last 12 months, including "the presence of mold, insects, liquid dripping from ceilings and meat and fat residue on walls, floors and equipment."

"The years of inspection reports leave little doubt that the Boar's Head plant's food safety plan must have been non-existent, " said food safety attorney, Bill Marler. "It is hard to wrap your head around how food could be produced in these conditions by this company and under the gaze of FSIS inspectors."

Boar's Head said it is appointing a new chief safety officer who will report directly to the company's CEO. It also said it would set up a new safety council made up of independent industry experts.