There is a simple question that the experts who study viruses do not always relish being asked. The question is this: what is it that makes one disease give you lasting immunity, while in another it is fleeting?
“That is complicated,” says Shane Crotty, from the La Jolla Institute for Immunology in California.
“That’s really difficult,” agrees Deenan Pillay, professor of virology at University College London. “You would have to speak to a geeky immunologist about that.”
Dan Davis is professor of immunology at Manchester University, author of The Beautiful Cure, a book about the immune system, and a fully accredited geeky immunologist. “This is a crucial frontier that is shortly going to be of paramount importance,” he begins rather more promisingly. And his