Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic <it>Escherichia coli </it>(VTEC) infection in Finland
<p>Abstract</p> <p>Background</p> <p>Verotoxigenic <it>E. coli </it>(VTEC) is the cause of severe gastrointestinal infection especially among infants. Between 10 and 20 cases are reported annually to the National Infectious Disease Register (NIDR) in Finland...
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| Format: | Article |
| Language: | English |
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BMC
2011-10-01
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| Series: | BMC Infectious Diseases |
| Online Access: | http://www.biomedcentral.com/1471-2334/11/275 |
| _version_ | 1818061235704299520 |
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| author | Jalava Katri Ollgren Jukka Eklund Marjut Siitonen Anja Kuusi Markku |
| author_facet | Jalava Katri Ollgren Jukka Eklund Marjut Siitonen Anja Kuusi Markku |
| author_sort | Jalava Katri |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>Verotoxigenic <it>E. coli </it>(VTEC) is the cause of severe gastrointestinal infection especially among infants. Between 10 and 20 cases are reported annually to the National Infectious Disease Register (NIDR) in Finland. The aim of this study was to identify explanatory variables for VTEC infections reported to the NIDR in Finland between 1997 and 2006. We applied a hurdle model, applicable for a dataset with an excess of zeros.</p> <p>Methods</p> <p>We enrolled 131 domestically acquired primary cases of VTEC between 1997 and 2006 from routine surveillance data. The isolated strains were characterized by virulence type, serogroup, phage type and pulsed-field gel electrophoresis. By applying a two-part Bayesian hurdle model to infectious disease surveillance data, we were able to create a model in which the covariates were associated with the probability for occurrence of the cases in the logistic regression part and the magnitude of covariate changes in the Poisson regression part if cases do occur. The model also included spatial correlations between neighbouring municipalities.</p> <p>Results</p> <p>The average annual incidence rate was 4.8 cases per million inhabitants based on the cases as reported to the NIDR. Of the 131 cases, 74 VTEC O157 and 58 non-O157 strains were isolated (one person had dual infections). The number of bulls per human population and the proportion of the population with a higher education were associated with an increased occurrence and incidence of human VTEC infections in 70 (17%) of 416 of Finnish municipalities. In addition, the proportion of fresh water per area, the proportion of cultivated land per area and the proportion of low income households with children were associated with increased incidence of VTEC infections.</p> <p>Conclusions</p> <p>With hurdle models we were able to distinguish between risk factors for the occurrence of the disease and the incidence of the disease for data characterised by an excess of zeros. The density of bulls and the proportion of the population with higher education were significant both for occurrence and incidence, while the proportion of fresh water, cultivated land, and the proportion of low income households with children were significant for the incidence of the disease.</p> |
| first_indexed | 2024-12-10T13:45:06Z |
| format | Article |
| id | doaj.art-7706be20ea8c4635b06d7480b31fc044 |
| institution | Directory Open Access Journal |
| issn | 1471-2334 |
| language | English |
| last_indexed | 2024-12-10T13:45:06Z |
| publishDate | 2011-10-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Infectious Diseases |
| spelling | doaj.art-7706be20ea8c4635b06d7480b31fc0442022-12-22T01:46:27ZengBMCBMC Infectious Diseases1471-23342011-10-0111127510.1186/1471-2334-11-275Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic <it>Escherichia coli </it>(VTEC) infection in FinlandJalava KatriOllgren JukkaEklund MarjutSiitonen AnjaKuusi Markku<p>Abstract</p> <p>Background</p> <p>Verotoxigenic <it>E. coli </it>(VTEC) is the cause of severe gastrointestinal infection especially among infants. Between 10 and 20 cases are reported annually to the National Infectious Disease Register (NIDR) in Finland. The aim of this study was to identify explanatory variables for VTEC infections reported to the NIDR in Finland between 1997 and 2006. We applied a hurdle model, applicable for a dataset with an excess of zeros.</p> <p>Methods</p> <p>We enrolled 131 domestically acquired primary cases of VTEC between 1997 and 2006 from routine surveillance data. The isolated strains were characterized by virulence type, serogroup, phage type and pulsed-field gel electrophoresis. By applying a two-part Bayesian hurdle model to infectious disease surveillance data, we were able to create a model in which the covariates were associated with the probability for occurrence of the cases in the logistic regression part and the magnitude of covariate changes in the Poisson regression part if cases do occur. The model also included spatial correlations between neighbouring municipalities.</p> <p>Results</p> <p>The average annual incidence rate was 4.8 cases per million inhabitants based on the cases as reported to the NIDR. Of the 131 cases, 74 VTEC O157 and 58 non-O157 strains were isolated (one person had dual infections). The number of bulls per human population and the proportion of the population with a higher education were associated with an increased occurrence and incidence of human VTEC infections in 70 (17%) of 416 of Finnish municipalities. In addition, the proportion of fresh water per area, the proportion of cultivated land per area and the proportion of low income households with children were associated with increased incidence of VTEC infections.</p> <p>Conclusions</p> <p>With hurdle models we were able to distinguish between risk factors for the occurrence of the disease and the incidence of the disease for data characterised by an excess of zeros. The density of bulls and the proportion of the population with higher education were significant both for occurrence and incidence, while the proportion of fresh water, cultivated land, and the proportion of low income households with children were significant for the incidence of the disease.</p>http://www.biomedcentral.com/1471-2334/11/275 |
| spellingShingle | Jalava Katri Ollgren Jukka Eklund Marjut Siitonen Anja Kuusi Markku Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic <it>Escherichia coli </it>(VTEC) infection in Finland BMC Infectious Diseases |
| title | Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic <it>Escherichia coli </it>(VTEC) infection in Finland |
| title_full | Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic <it>Escherichia coli </it>(VTEC) infection in Finland |
| title_fullStr | Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic <it>Escherichia coli </it>(VTEC) infection in Finland |
| title_full_unstemmed | Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic <it>Escherichia coli </it>(VTEC) infection in Finland |
| title_short | Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic <it>Escherichia coli </it>(VTEC) infection in Finland |
| title_sort | agricultural socioeconomic and environmental variables as risks for human verotoxigenic it escherichia coli it vtec infection in finland |
| url | http://www.biomedcentral.com/1471-2334/11/275 |
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