小编摘要：为了引起国际社会对烟草危害人类健康的重视，世界卫生组织1987年11月建议将每年的4月7日定为“世界无烟日（World No-Tobacco Day）”，并于1988年开始执行。自1989年起，世界无烟日改为每年的5月31日。
Every year, Americans observe the Great American Smoke Out, a day set aside to encourage smokers to go without a cigarette for one day. Suddenly giving up a habit is referred to as "going cold turkey." In Knoxville, Tennessee, smokers on one anniversary could trade in their cigarettes for a real cold turkey.
One day events like The Great American Smoke Out or World No Tobacco Day usually get publicity, but it was impossible to scientifically determine their effectiveness.
The Google search engine changed all of that. Joanna Cohen heads the Global Tobacco Initiative at Johns Hopkins School of Public Health.
"Today with the tools of Google News and being able to analyze Internet search queries, you can actually pinpoint the effects of actual days," noted Cohen. The researchers picked several countries in Latin America for their study. Among the reasons: Spanish is the main language so the researchers were able to examine the impact of World No Tobacco Day in many countries with only one language.
What they found was encouraging for health officials who are trying to get people to quit smoking.
"If you look at people searching for how to quit smoking which would be the logical next step - awareness and then interest in cessation - we see on average about 40 percent increase in all those countries in all years from 2000 onward," said John Ayers, the study's lead author who spoke to VOA via Skype.
The researchers say these spikes in interest on how to quit smoking could have potentially large health implications.
"What our study shows is that World No Tobacco Day is having a significant impact on raising interest in and awareness of cessation in these developing countries," added Ayers.
The researchers say this information will help the health ministries in countries around the world because if they know that their citizens are interested in information on how to stop smoking, the ministries can provide better online information on World No Tobacco Day to help people kick the smoking habit.