Outbreaks of Tularemia in a Boreal Forest Region Depends on Mosquito Prevalence
Open Access
- 28 November 2011
- journal article
- research article
- Published by Oxford University Press (OUP) in The Journal of Infectious Diseases
- Vol. 205 (2), 297-304
- https://doi.org/10.1093/infdis/jir732
Abstract
Background. We aimed to evaluate the potential association of mosquito prevalence in a boreal forest area with transmission of the bacterial disease tularemia to humans, and model the annual variation of disease using local weather data. Methods. A prediction model for mosquito abundance was built using weather and mosquito catch data. Then a negative binomial regression model based on the predicted mosquito abundance and local weather data was built to predict annual numbers of humans contracting tularemia in Dalarna County, Sweden. Results. Three hundred seventy humans were diagnosed with tularemia between 1981 and 2007, 94% of them during 7 summer outbreaks. Disease transmission was concentrated along rivers in the area. The predicted mosquito abundance was correlated (0.41, P < .05) with the annual number of human cases. The predicted mosquito peaks consistently preceded the median onset time of human tularemia (temporal correlation, 0.76; P < .05). Our final predictive model included 5 environmental variables and identified 6 of the 7 outbreaks. Conclusions. This work suggests that a high prevalence of mosquitoes in late summer is a prerequisite for outbreaks of tularemia in a tularemia-endemic boreal forest area of Sweden and that environmental variables can be used as risk indicators.Keywords
This publication has 16 references indexed in Scilit:
- Transstadial Transmission ofFrancisella tularensis holarcticain Mosquitoes, SwedenEmerging Infectious Diseases, 2011
- Molecular Detection of PersistentFrancisella tularensisSubspeciesholarcticain Natural WatersInternational Journal of Microbiology, 2011
- Landscape Epidemiology of Tularemia Outbreaks in SwedenEmerging Infectious Diseases, 2009
- Molecular Epidemiology, Evolution, and Ecology of FrancisellaAnnals of the New York Academy of Sciences, 2007
- The 2000 Tularemia Outbreak: A Case-Control Study of Risk Factors in Disease-Endemic and Emergent Areas, SwedenEmerging Infectious Diseases, 2002
- Waterborne Outbreak of Tularemia Associated with Crayfish FishingEmerging Infectious Diseases, 2001
- A note on a general definition of the coefficient of determinationBiometrika, 1991
- Negative binomial and mixed Poisson regressionThe Canadian Journal of Statistics / La Revue Canadienne de Statistique, 1987
- A Biometrics Invited Paper. The Analysis and Selection of Variables in Linear RegressionPublished by JSTOR ,1976
- NATURAL NIDALITY OF TRANSMISSIBLE DISEASESThe American Journal of the Medical Sciences, 1966