Potential Biases Arising from Epidemic Dynamics in Observational Seroprotection Studies. Author(s): Kahn R, Kennedy-Shaffer L, Grad YH, Robins JM, Lipsitch M|Journal: Am J Epidemiol|PMID: 32870977| September 2020 The extent and duration of immunity following SARS-CoV-2 infection are critical outstanding questions about the epidemiology of this novel virus,…