A two-phase dynamic contagion model for COVID-19

Abstract

In this paper, we propose a continuous-time stochastic intensity model, namely, two-phase dynamic contagion process (2P-DCP), for modelling the epidemic contagion of COVID-19 and investigating the lockdown effect based on the dynamic contagion model introduced by Dassios and Zhao [24] . It allows randomness to the infectivity of individuals rather than a constant reproduction number as assumed by standard models. Key epidemiological quantities, such as the distribution of final epidemic size and expected epidemic duration, are derived and estimated based on real data for various regions and countries. The associated time lag of the effect of intervention in each country or region is estimated. Our results are consistent with the incubation time of COVID-19 found by recent medical study. We demonstrate that our model could potentially be a valuable tool in the modeling of COVID-19. More importantly, the proposed model of 2P-DCP could also be used as an important tool in epidemiological modelling as this type of contagion models with very simple structures is adequate to describe the evolution of regional epidemic and worldwide pandemic.

COVID-19 transmission risk in Surabaya and Sidoarjo: an inhomogeneous marked Poisson point process approach

“…The analysis in this regard is able to exploit the disease spread on an individual basis and detect interaction between cases, which is not observable using aggregated data (Chen et al. 2021 ; Briz-Redón et al. 2022 ; Park et al.…”

Resemblance of the power-law scaling behavior of a non-Markovian and nonlinear point processes

“…This temporal pattern can be encoded by a list of event times or inter-event times. Numerous examples of phenomena described by event times or inter-event times include contraction of infectious diseases [4], order execution within financial markets [5], musical rhythm [6], earthquakes [7], traffic accidents [8], human heartbeat [9] or formation of queues [10]. Such phenomena are driven by various complex mechanisms with a degree of randomness and causality (e.g., earthquakes trigger aftershocks).…”

“…Unlike in the Poisson process, in the Hawkes process time increments are no longer independent. Having such embedded memory property Hawkes process has found numerous applications in finance [11] and other fields [4,8,12,13]. Recently it was shown that a certain class of nonlinear Hawkes processes can reproduce power-law distributions [14], which may appeal to practitioners dealing with complex systems exhibiting power-law distributions, such as financial markets.…”

Desafíos de la pandemia de COVID-19

“…An Fac med. 2021;82(1):3-4 mica de la transmisión del SARS-CoV-2 (7) . Sin embargo, a pesar del impacto que la pandemia también ha tenido en la actividad de la comunidad científica (8) , el esfuerzo de los investigadores y los centros académicos del mundo continúa.…”

“…Solo tomando el caso de la ciencia, se ha observado que las naciones con menor desarrollo científico y tecnológico han tenido más dificultades para enfrentar la emergencia sanitaria, tanto en las intervenciones asistenciales como en las preventivas (7,9) . En el Perú, la situación fue desesperada en los primeros momentos de la pandemia, y aunque mejoró después, muchas de las medidas implementadas corren el riesgo de ser temporales, si es que en poco tiempo no se establecen las bases de un desarrollo científico y tecnológico sostenible.…”