Viral epidemics have now become very common, much more common than they used to be in the past; some of them have become very famous, for example Ebola, HIV, malaria, Zika virus and bird flu. Others have been with us, with variants of the same virus, for more than a century: just think about the common flu, which killed up to fifty million people during World War I. yet other epidemics seem to have not solution, malaria being one of these. People...