Ticks in the wrong boxes: assessing error in blanket-drag studies due to occasional sampling

Particle and Fibre Toxicology

Andrew DM Dobson¹ 

[1] School of Biological and Environmental Sciences, University of Stirling, Cottrell Building, FK9 4LA, Stirling, UK

关键词: Disease risk;    Error;    Bias;    Blanket-dragging;    Sampling;    Ticks;   

Others  :  823655
DOI  :  10.1186/1756-3305-6-344

 received in 2013-11-11, accepted in 2013-12-06,  发布年份 2013

【 摘 要 】

Background

The risk posed by ticks as vectors of disease is typically assessed by blanket-drag sampling of host-seeking individuals. Comparisons of peak abundance between plots – either in order to establish their relative risk or to identify environmental correlates – are often carried out by sampling on one or two occasions during the period of assumed peak tick activity.

Methods

This paper simulates this practice by ‘re-sampling’ from model datasets derived from an empirical field study. Re-sample dates for each plot are guided by either the previous year’s peak at the plot, or the previous year’s peak at a similar, nearby plot. Results from single, double and three-weekly sampling regimes are compared.

Results

Sampling on single dates within a two-month window of assumed peak activity has the potential to introduce profound errors; sampling on two dates (double sampling) offers greater precision, but three-weekly sampling is the least biased.

Conclusions

The common practice of sampling for the abundance of host-seeking ticks on single dates in each plot-year should be strenuously avoided; it is recommended that field acarologists employ regular sampling throughout the year at intervals no greater than three weeks, for a variety of epidemiological studies.

【 授权许可】

   
2013 Dobson; licensee BioMed Central Ltd.

【 图 表 】

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