Dr. Stephen Beckett and Prof. Joshua Weitz contributed to a new study published in ISME J that measured the infected fraction of Prochlorococcus cells in the North Pacific ocean. The iPolony method suggests that less than 2% of Prochlorococcus cells in the surface ocean are infected at any time by T4- or T7-like viruses, which suggests these viruses are not a major source of mortality in this ecosystem despite being present in large numbers.