CO2 flagging - an improved method for the collection of questing ticks

Area of Science:

• Veterinary Entomology
• Medical Entomology
• Pathogen Surveillance

Background:

• Tick-borne pathogen studies often rely on collecting ticks from the environment.
• Efficient tick collection methods are crucial for obtaining adequate sample sizes.
• Traditional flagging methods can be enhanced to improve tick yield.

Purpose of the Study:

• To evaluate the efficacy of a novel tick collection method using a sweep flag enhanced with dispersed carbon dioxide (CO2).
• To compare the tick collection efficiency of the CO2-enhanced flag against a traditional CO2-free flag.
• To assess the impact of CO2 on the attraction of different tick species and developmental stages.

Main Methods:

• A comparative study was conducted in March-April 2011 in Cluj County, Romania.
• Two types of sweep flags were used simultaneously: one enhanced with a CO2 dispersal system and a control flag without CO2.
• Thirty sampling events were performed at each of two locations, with tick counts (species and developmental stages) recorded for each flag type.

Main Results:

• The CO2-enhanced flag captured significantly more Ixodes ricinus ticks (2411, 59%) than the CO2-free flag (1670, 41%).
• A higher proportion of Dermacentor marginatus ticks were also captured using the CO2-enhanced flag (100, 53.8%) compared to the control (86, 46.2%).
• CO2 concentrations on the enhanced flag surface ranged from 756.5 to 1135.0 ppm, with a mean of 848.9 ppm.

Conclusions:

• The CO2-enhanced sweep flag significantly improved the attraction and collection of Ixodes ricinus ticks (p<0.0001).
• The enhancement did not yield a statistically significant increase in Dermacentor marginatus tick collection.
• The findings suggest CO2 dispersal is a valuable improvement for flagging methods targeting specific tick species like I. ricinus.