Physics Department, Università degli Studi di Napoli 'Federico II', Napoli, Italy.
Consiglio Nazionale delle Ricerche (CNR), Institute Superconductors, Oxides and other Innovative Materials and Devices (SPIN), Napoli, Italy.
PLoS One. 2023 Nov 14;18(11):e0293416. doi: 10.1371/journal.pone.0293416. eCollection 2023.
We propose a deterministic epidemic model to describe the transition between two variants of the same virus, through the combination of a series of realistic mechanisms such as partial cross immunity, waning immunity for vaccinated individuals and a novel data-based algorithm to describe the average immunological status of the population. The model is validated on the evolution of Covid-19 in Italy, during the period in which the transition between Delta and Omicron variant occurred, with very satisfactory agreement with the experimental data. According to our model, if the vaccine efficacy had been equal against Delta and Omicron variant infections, the transition would have been smoothed and the epidemic would have gone extinct. This circumstance confirms the fundamental role of vaccines in combating the epidemic, and the importance of identifying vaccines capable of intercepting new variants.
我们提出了一个确定性的传染病模型，通过结合一系列现实机制，如部分交叉免疫、接种人群免疫力下降，以及一种新颖的基于数据的算法来描述人群的平均免疫状态，来描述同一病毒两种变体之间的转变。该模型在意大利新冠病毒进化期间进行了验证，在此期间，德尔塔和奥密克戎变体之间发生了转变，与实验数据非常吻合。根据我们的模型，如果疫苗对德尔塔和奥密克戎变体的感染效果相同，那么这种转变将更加平滑，疫情也将消失。这种情况证实了疫苗在对抗疫情方面的重要作用，也凸显了识别能够拦截新变体的疫苗的重要性。
