Investigating the spatial risk distribution of West Nile virus disease in birds and humans in southern Ontario from 2002 to 2005
2007

West Nile Virus Risk in Birds and Humans in Southern Ontario

publication 10 minutes Evidence: moderate

Author Information

Author(s): Beroll Heidi, Berke Olaf, Wilson Jeffrey, Barker Ian K

Primary Institution: University of Guelph

Hypothesis

What is the spatial risk distribution of West Nile virus disease in birds and humans in southern Ontario from 2002 to 2005?

Conclusion

The study indicates a significant relationship between the spatial pattern of West Nile virus risk in humans and birds.

Supporting Evidence

  • The annual WNv cause-specific mortality fractions in birds for 2002 to 2005 were 31.9, 22.0, 19.2 and 25.2 positive birds per 100 birds tested.
  • The annual human WNv incidence rates for 2002 to 2005 were 2.21, 0.76, 0.13 and 2.10 human cases per 100,000 population.
  • The relative risk of human WNv disease increased by the factor 1.44 with every 10 positive birds per 100 tested.

Takeaway

This study looked at how the West Nile virus affected birds and humans in southern Ontario over a few years, showing that areas with more sick birds also had more sick people.

Methodology

Choropleth maps and Poisson regression analysis were used to model the spatial risk distribution and identify disease clusters.

Potential Biases

Potential biases include public awareness affecting reporting rates and variations in testing practices among public health units.

Limitations

The study relied on voluntary reporting of dead birds, which may have led to inconsistent data collection across public health units.

Participant Demographics

The study focused on public health units in southern Ontario, Canada.

Statistical Information

P-Value

0.057

Confidence Interval

95% CI = 0.22–0.96

Statistical Significance

p<0.05

Digital Object Identifier (DOI)

10.1186/1478-7954-5-3

Want to read the original?

Access the complete publication on the publisher's website

View Original Publication