SIR-SI model with a Gaussian transmission rate: Understanding the dynamics of dengue outbreaks in Lima, Peru

PLoS One. 2023 Apr 13;18(4):e0284263. doi: 10.1371/journal.pone.0284263. eCollection 2023.

Abstract

Introduction: Dengue is transmitted by the Aedes aegypti mosquito as a vector, and a recent outbreak was reported in several districts of Lima, Peru. We conducted a modeling study to explain the transmission dynamics of dengue in three of these districts according to the demographics and climatology.

Methodology: We used the weekly distribution of dengue cases in the Comas, Lurigancho, and Puente Piedra districts, as well as the temperature data to investigate the transmission dynamics. We used maximum likelihood minimization and the human susceptible-infected-recovered and vector susceptible-infected (SIR-SI) model with a Gaussian function for the infectious rate to consider external non-modeled variables.

Results/principal findings: We found that the adjusted SIR-SI model with the Gaussian transmission rate (for modelling the exogenous variables) captured the behavior of the dengue outbreak in the selected districts. The model explained that the transmission behavior had a strong dependence on the weather, cultural, and demographic variables while other variables determined the start of the outbreak.

Conclusion/significance: The experimental results showed good agreement with the data and model results when a Bayesian-Gaussian transmission rate was employed. The effect of weather was also observed, and a strong qualitative relationship was obtained between the transmission rate and computed effective reproduction number Rt.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aedes*
  • Animals
  • Bayes Theorem
  • Bivalvia*
  • Dengue Virus*
  • Dengue* / epidemiology
  • Disease Outbreaks
  • Humans
  • Mosquito Vectors
  • Peru / epidemiology

Grants and funding

This study was supported by the Universidad Tecnologica del Peru (Grant reference No. P-2020-LIM-01; grant recipient: Max Carlos Ramírez-Soto) and the PRONII - PROCIENCIA - CONACYT – FEEI, Paraguay (Grant recipient: Dr. Christian E. Schaerer and Dr. Diego H. Stalder). The funders had no role in the study design, data collection and analysis, decision to publish or the preparation of the manuscript.