Children exposed to environmental tobacco smoke have a signficantly greater risk of dying of sudden infant death syndrome. This could either be due to the their mother's smoking during pregnancy, or the extended exposure to ETS . According to World Health Organisation estimates, children under 11, whose parents smoke at least 10 cigarettes a day, have a 40 per cent higher chance of contracting bronchitis, than children of non smoking parents. These children are also likely to get more coughs and cold and suffer acute upper and lower respiratory tract infections.