Tobacco epidemic disproportionately affect low and middle-income countries, where more than 80% of the world’s smokers now live

For Jasmin Bueno, aged seven, and her brother Aaron, aged six, there is little that can make swallowing chemo-profilactic pills any less bitter. But the tablets they stoically gulp down daily during the next six months are the best protection they can get from contracting tuberculosis.

Teenagers are twice as likely to try smoking and alcohol after playing popular video games, experts have warned.