blog posts Suppression of COVID-19 peaks reflect time-dependent social activity, not herd immunity Apr 14, 2021 9:00 am by Ariana ManglavitiResearch Share on Facebook Tweet Email Images Researchers showed that a temporary state of collective immunity - 'transient collective immunity' - emerged during early, fast-paced stages of the epidemic. But subsequent surges continued to appear because of changing social behaviors. Share on Facebook Tweet Email