Definición actual(1) de "inmunidad de grupo" de la O. M. S.: "concept used for vaccination, in which a population can be protected from a certain virus if a threshold of vaccination is reached". Sin embargo, en octubre(2) decía: "when a population is immune either through vaccination or immunity developed through previous infection". (1)
www.who.int/news-room/q-a-detail/coronavirus-disease-covid-19-serology (2)
web.archive.org/web/20201022012953/https://www.who.int/news-room/q-a-d 
