An Anglo-American team of researchers has devised a new computational method for quantifying Epstein-Barr virus (EBV) directly from human genome sequences and used this to identify 22 genes that link higher levels of the virus to a range of chronic diseases. The new method sets the scene for further exploration of biobank DNA sequence data to gain greater understanding of the nature and the role of the human virome, the 10(13) – largely unstudied – viral particles that coexist in humans.