Forest Structure and Roe Deer Abundance Predict Tick-Borne Encephalitis Risk in Italy
2009

Forest Structure and Roe Deer Abundance Predict Tick-Borne Encephalitis Risk in Italy

Sample size: 198 publication 10 minutes Evidence: moderate

Author Information

Author(s): Rizzoli Annapaola, Hauffe Heidi C., Tagliapietra Valentina, Neteler Markus, Rosà Roberto

Primary Institution: Fondazione Edmund Mach - Centro Ricerca e Innovazione, Michele all'Adige, Italy

Hypothesis

Substantial changes in land and wildlife management practices which improve habitat suitability for the principal TBE reservoir hosts (small mammals), and increase the number of non-competent tick hosts (roe deer) are among the most crucial factors driving the circulation potential of TBE virus and, consequently, the pattern of TBE emergence in humans.

Conclusion

Changes in forest structure and roe deer abundance are likely key factors affecting the risk of tick-borne encephalitis emergence in humans in northern Italy.

Supporting Evidence

  • 198 confirmed human TBE cases were reported in the study area from 1992 to 2006.
  • The mean annual incidence of TBE in TBE-positive provinces increased from 0.06 in 1992 to 0.88 in 2006.
  • Roe deer density was significantly higher in TBE-positive provinces compared to TBE-negative provinces.
  • Changes in forest structure were correlated with TBE incidence.
  • Most TBE cases were reported in males and older adults.

Takeaway

This study found that changes in forests and more deer can lead to more cases of tick-borne encephalitis, a disease spread by ticks.

Methodology

The study analyzed the correlation between TBE incidence and various factors including climatic variables, forest structure, and roe deer abundance using datasets from 1992 to 2006.

Potential Biases

Potential biases may arise from the reliance on reported clinical cases and the accuracy of historical data.

Limitations

The study is limited by the availability of historical data on forest cover and wildlife abundance.

Participant Demographics

The majority of TBE cases were male (70.3%) and the highest incidence was in patients over 50 years old.

Statistical Information

P-Value

p=0.012

Statistical Significance

p<0.05

Digital Object Identifier (DOI)

10.1371/journal.pone.0004336

Want to read the original?

Access the complete publication on the publisher's website

View Original Publication