Cryo-EM cools down swine fever.

African swine fever virus (ASFV) is among the most complex DNA viruses known. Outbreaks have killed millions of swine around the world, and there is currently no vaccine. Three recent papers report the cryo-EM structure of the complete ASFV virion, comprising a viral particle of multiple layers, and resolve the major outer-capsid protein p72 to higher resolution. Progress in these reports provides a further understanding of the structure-function relationships of large viruses and should aid in ASFV vaccine development.