Massachusetts on Tuesday went further than any other state in trying to keep e-cigarettes out of consumers’ hands, with its governor declaring a public health emergency and ordering a four-month prohibition on the sale of all vaping products.

Hours later, Juul Labs, the e-cigarette company that has become synonymous with vaping, said that it had begun a restructuring plan that could result in layoffs. Division heads have been ordered to submit specific plans by Wednesday to deal with financial headwinds, according to a person familiar with the company’s strategy and finances.

The two developments are the latest in an escalating nationwide backlash against vaping, as the number of people who have developed severe lung illnesses after using vaping devices continues to climb. The latest tally, from the Centers for Disease Control and Prevention, is 530 cases, but a top C.D.C. official told a Congressional committee on Tuesday that the agency will announce more cases this week. Nine deaths from the vaping-related ailments have been reported so far.

Also on Tuesday, the California Department of Health urged state residents to refrain from all vaping “no matter the substance or source, until current investigations are complete.”