BMC Infectious Diseases

official impact factor 2.83

Open Access Research article

An individual-based network model to evaluate interventions for controlling pneumococcal transmission

Diana Karlsson1,2,3*, Andreas Jansson1, Birgitta H Normark2,3 and Patric Nilsson1

Author Affiliations

1 Molecular Biology, School of Life Sciences, University of Skövde, SE-541 28 Skövde, Sweden

2 Department of Bacteriology, Swedish Institute for Infectious Diseases Control, Karolinska Institutet, SE-171 82 Solna, Sweden

3 Department of Microbiology, Tumor Biology, and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden

For all author emails, please log on.

BMC Infectious Diseases 2008, 8:83 doi:10.1186/1471-2334-8-83

Published: 17 June 2008

Abstract

Background

Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide, but also a common colonizer of the upper respiratory tract. The emergence and spread of antibiotic resistant pneumococcal strains has threatened effective therapy. The long-term effects of measures aiming to limit pneumococcal spread are poorly understood. Computational modeling makes it possible to conduct virtual experiments that are impractical to perform in real life and thereby allows a more full understanding of pneumococcal epidemiology and control efforts.

Methods

We have developed a contact network model to evaluate the efficacy of interventions aiming to control pneumococcal transmission. Demographic data from Sweden during the mid-2000s were employed. Analyses of the model's parameters were conducted to elucidate key determinants of pneumococcal spread. Also, scenario simulations were performed to assess candidate control measures.

Results

The model made good predictions of previous findings where a correlation has been found between age and pneumococcal carriage. Of the parameters tested, group size in day-care centers was shown to be one of the most important factors for pneumococcal transmission. Consistent results were generated from the scenario simulations.

Conclusion

We recommend, based on the model predictions, that strategies to control pneumococcal disease and organism transmission should include reducing the group size in day-care centers.