Modelling the Seasonal Epidemics of Respiratory Syncytial Virus in Young Children

Abstract

BackgroundRespiratory syncytial virus (RSV) is a major cause of paediatric morbidity. Mathematical models can be used to characterise annual RSV seasonal epidemics and are a valuable tool to assess the impact of future vaccines.ObjectivesConstruct a mathematical model of seasonal epidemics of RSV and by fitting to a population-level RSV dataset, obtain a better understanding of RSV transmission dynamics.MethodsWe obtained an extensive dataset of weekly RSV testing data in children aged less than 2 years, 2000–2005, for a birth cohort of 245,249 children through linkage of laboratory and birth record datasets. We constructed a seasonally forced compartmental age-structured Susceptible-Exposed-Infectious-Recovered-Susceptible (SEIRS) mathematical model to fit to the seasonal curves of positive RSV detections using the Nelder-Mead method.ResultsFrom 15,830 specimens, 3,394 were positive for RSV. RSV detections exhibited a distinct biennial seasonal pattern with alternating sized peaks in winter months. Our SEIRS model accurately mimicked the observed data with alternating sized peaks using disease parameter values that remained constant across the 6 years of data. Variations in the duration of immunity and recovery periods were explored. The best fit to the data minimising the residual sum of errors was a model using estimates based on previous models in the literature for the infectious period and a slightly lower estimate for the immunity period.ConclusionsOur age-structured model based on routinely collected population laboratory data accurately captures the observed seasonal epidemic curves. The compartmental SEIRS model, based on several assumptions, now provides a validated base model. Ranges for the disease parameters in the model that could replicate the patterns in the data were identified. Areas for future model developments include fitting climatic variables to the seasonal parameter, allowing parameters to vary according to age and implementing a newborn vaccination program to predict the effect on RSV incidence.

Seasonal variability of respiratory syncytial virus infection in the Top End of the Northern Territory (2012–2014)

“…Within Australia, RSV infections in Alice Springs, Central Australia (23.7°S) occur throughout the year, but peak in winter; which is a typical Southern Australian pattern and similar to the Central Australian winter influenza season. A high burden of RSV disease in Indigenous compared to non‐Indigenous infants has been previously described .…”

Respiratory Syncytial Virus Immunization in Sakarya, Turkey

“…15 In Turkey, it is estimated that there are 30,000-45,000 hospital admissions per year due to RSV among children under five years. 7 In a study in Turkey, 376 children under two years of age were hospitalized every year in Bursa due to RSV-RTI and this figure is estimated as 18,800 for Turkey (12).…”

Systematic review on respiratory syncytial virus epidemiology in adults and the elderly in Latin America

“…Respiratory Syncytial Virus (RSV) was first identified in chimpanzees in 1955 and, shortly after, recognized as a cause of viral bronchiolitis in human infants (Hall 2001;Falsey et al, 2005;Schweitzer and Justice 2018). Since then, RSV has been widely acknowledged as a major pathogen in newborn infants and young children (Moore et al, 2014;Piedimonte and Perez 2014;Gökçe et al, 2017), being associated with severe forms of disease.…”