Sistema FMUSP-HC: Faculdade de Medicina da Universidade de São Paulo (FMUSP) e Hospital das Clínicas da FMUSPLORIA, JenniferALBANI, Vinicius V. L.COUTINHO, Francisco A. B.COVAS, Dimas T.STRUCHINER, Claudio J.ZUBELLI, Jorge P.MASSAD, Eduardo2023-08-162023-08-162023PLOS ONE, v.18, n.5, article ID e0285466, 18p, 20231932-6203https://observatorio.fm.usp.br/handle/OPI/54811In this paper we calculate the variation of the estimated vaccine efficacy (VE) due to the time-dependent force of infection resulting from the difference between the moment the Clinical Trial (CT) begins and the peak in the outbreak intensity. Using a simple mathematical model we tested the hypothesis that the time difference between the moment the CT begins and the peak in the outbreak intensity determines substantially different values for VE. We exemplify the method with the case of the VE efficacy estimation for one of the vaccines against the new coronavirus SARS-CoV-2.engopenAccessphasetransmissionarticleCopyright PUBLIC LIBRARY SCIENCE10.1371/journal.pone.0285466Multidisciplinary Sciences