Well germ theory led to the development of the ideas of hygeine and antibiotics, so that's really the clear winner here. I'd like to give an honorable mention to vaccines -another extension- because in order for people to benefit from most medical technology, they need to get through childhood, and vaccinations against measles, smallpox, Tb etc have played a huge part in this, and continue to do so. Although
measles is still one of the two biggest childhood killers in Africa .
Perhaps we should add charitable donations/financial support as an option?