The number of vaping-related lung injury cases jumped to 805 and the number of deaths to 12, but the specific causes of the illnesses are undetermined, the Centers for Disease Control and Prevention reported Thursday.

The CDC report, from 46 states and one territory as of Tuesday, was an increase from last week when the tally was 530 vaping-related lung cases and seven deaths.

The confirmed deaths include two in California, two in Kansas and one each in Florida, Georgia, Illinois, Indiana, Minnesota, Mississippi, Missouri and Oregon. The Mississippi death was announced by state officials Thursday.

The latest survey found that 72% of the lung injury cases involved males and 16% were from users under 18 years of age.

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The Food and Drug Administration said last week that it launched a criminal probe into the spike in vaping-related illnesses.The inquiry will focus on the products, where they were purchased and how they were used.

"We do not yet know the specific cause of these lung injuries," the CDC said in a statement. "The investigation has not identified any specific e-cigarette or vaping product (devices, liquids, refill pods, and/or cartridges) or substance that is linked to all cases."

The CDC recommended that any user with concerns about health risks should consider refraining from using e-cigarettes or vaping products.

Regardless of the latest investigation, the CDC said, anyone using an e-cigarette or vaping product should not buy any vaping products off the street or modify or add any substances to the products that are not intended by the manufacturer.

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The latest figures come amid upheaval in the industry. Juul Labs, the vaping giant, replaced its CEO on Wednesday with an executive from Big Tobacco. The company announced it will suspend all TV, print and digital ads, along with some of its lobbying efforts.

In Washington, Rep. Raja Krishnamoorthi, D-Ill., chairman of the House Oversight subcommittee on economic and consumer policy, wrote to four e-cigarette companies to "strongly" request they follow Juul's lead to stop all print, broadcast and digital advertising of their products in the USA.

The letter was sent to Fontem Ventures, Japan Tobacco International, Reynolds American and NJOY. Fontem Ventures said in a statement that it supports initiatives to prevent youth access to its products, and Reynolds American said it is giving the letter “careful consideration.” Reuters reported. The other two companies did not immediately respond to requests for comment.

Ned Sharpless, acting commissioner for the FDA, said under questioning by the House energy and commerce subcommittee on Wednesday that in retrospect, the FDA "should have begun regulating these devices sooner."

Sharpless pledged that the agency would speed up its time in examining e-cigarette-related applications. "We're going to catch up," he said.

Vermont Gov. Phil Scott is exploring whether the state should institute a ban on the sale of vaping products, as New York, Massachusetts and Rhode Island have.

"The governor is concerned about the health impacts of vaping products, particularly on Vermont's youth," said Rebecca Kelley, his communication director, the Bennington Banner reported Thursday.

This week, Massachusetts Gov. Charlie Baker ordered a four-month statewide ban on the sale of flavored and unflavored vaping products bought online and in retail stores. Wednesday, Rhode Island Gov. Gina Raimondo, in an executive order, banned the sale of flavored electronic nicotine-delivery system products.

New York Gov. Andrew Cuomo proposed a ban on the sale of flavored electronic cigarettes Sept. 15.

As some states move to ban all e-cigarette products, Walmart announced it discontinued sales of vaping products.

Contributing: The Associated Press