Four ways to respond to vaccine sceptics — and maybe even convince them

For most of the 20th century, more than 60,000 people died in the US from polio, diphtheria and small pox each year. In 2016, the American death toll from these diseases was zero. Around the globe, two to three million deaths from these diseases and others, including measles, rubella and tetanus, are prevented each year.These remarkable statistics are a triumph of medicine and the single most effective public health measure in history: global vaccination programmes.