One out of nine Koreans now smoke heat-not-burn (HNB) cigarettes, showing a viral proliferation in one of the world’s most heavily smoking countries in just 17 months since the type was introduced in Korea. 

According to data released by the Ministry of Economy and Finance on Friday, 288 million packs of cigarettes were sold last month in Korea, of which 11.3 percent, or 35 million packs, were HNM kinds. The e-cigarette share topped 11 percent now, up from 7.3 percent a year ago.