On 12 December 2017, Professor Stephen Hawking delivered a keynote speech at an event in Cambridge to mark the one billion treatments Sightsavers and partners have delivered to people affected by neglected tropical diseases (NTDs). In his speech, Professor Hawking highlighted the work and legacy of his father, Dr Frank Hawking who, in the 1950s, was one of the first people to conduct research into and develop treatment for an NTD known as lymphatic filariasis (LF). The preventative chemotherapy drug diethylcarbamazine (DEC) which he developed, is still widely used today.