Public health expert worries e-cigarette panic is ruining "single biggest public health opportunity" in 120 years Researchers are working hard to determine the cause of more than 500 reported cases of lung illness affecting e-cigarette users. But even before this outbreak, e-cigarettes divided the medical community. Public Health England describes e-cigarettes as "at least 95% less harmful than tobacco cigarettes" – a claim New York University professor David Abrams agrees with. Abrams tells "CBS This Morning" Tony Dokoupil why he's concerned about what the current panic about e-cigarette safety could mean for public health.