Skip to main content
Download PDF

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

Parasites & Vectors volume 5, Article number: 125 (2012) Cite this article

Abstract

Background

Most epidemiological studies on tick-borne pathogens involve collection of ticks from the environment. An efficient collection method is essential for large sample pools. Our main aim was to evaluate the efficacy of a new method, where traditional flagging was enhanced by the use of CO2 dispersed into the white flannel. The CO2 was spread through a rubber hose network inserted into the flag blanket. The research was conducted in spring, in March-April 2011 in two locations from Cluj County, Romania.

Methods

The research was conducted in March-April 2011 in two locations from Cluj County, Romania. The flag to be tested contained a fine silicone rubber hose network which dispersed the CO2 in the shaft. On each collection site n=30 samplings were performed. Each sampling consisted in the simultaneous use of both flags (with and without CO2) by two persons. The CO2 concentration level on the flag canvas surface was measured. The efficacy of the method was determined by counting comparatively the total number of ticks and separate developmental stage count.

Results

Using the CO2 improved flag, 2411 (59%) Ixodes ricinus and 100 (53.8%) Dermacentor marginatus ticks were captured, while the CO2-free flag accounted for the collection of 1670 I. ricinus (41%) and 86 (46.2%) D. marginatus ticks. The addition of CO2 prompted a concentration difference on the surface of the flag ranging between 756.5 and 1135.0 ppm with a mean value of 848.9 ppm.

Conclusion

The study showed that the CO2 enhanced sweep flag increased the ability of I. ricinus (p < 0001) but not of D. marginatus to be attracted to the flag blanket.

Background

Ticks (suborder Ixodida) are obligate blood-sucking acarines attacking a wide variety of hosts from all tetrapod vertebrate classes [1, 2]. Around 700 species of hard ticks are currently recognized as valid species [1]. Most of these species are three-host ticks (i.e. each stage detaches after engorgement) [3, 4]. Regardless of the number of hosts, each tick must find a suitable host. In three-host ticks, most of their multiannual life is not spent attached to the host but as free-living organisms. Thus, newly hatched larvae, unfed nymphs and unfed adults are in a permanent host finding state. Host detection and attachment in Ixodidae is achieved through three main alternative behavioral patterns: questing, hunting and tick-host cohabitation (nidiculous ticks) [4].

Most epidemiological studies on tick-borne pathogens involve collection of ticks from the environment [5]. Thus, an efficient collection method is essential for large datasets. Tick collection methods had been reviewed by Gray [6]. He divided these methods into four major categories: (1) flagging or dragging methods; (2) trapping using carbon dioxide baits; (3) collecting from hosts and (4) walking (i.e. on the clothes of the collectors). Despite all these methods are relative and do not estimate density (number per unit area) or absolute size (total number as measured in mark-release-recapture methods) [7], each of these has a variable efficacy depending on several factors (i.e. habitat type, tick species, developmental stage etc.). Nevertheless, all methods have been improved over the time in order to increase their efficacy [8].

One of the most important ticks species (regarding its range, abundance, and vectorial importance) in the Palearctic region, with tendency to expand its spread in Northern Europe [9, 10], is I xodes ricinus[11]. The host seeking strategy of all developmental stages in I. ricinus is questing, when ticks are typically positioned on the vegetation with their legs extended, waiting for a moving host to which they attach [12]. Though, questing is a complex behavioral process, which involves responses to stimuli like host movement, concentration of environmental carbon dioxide and increase of temperature [4]. The most commonly used method for collection of questing ticks is flagging. However, flagging stimulates only the tick sensor for movement, and leaves the other two sensorial components of questing (i.e. carbon dioxide and temperature) unexploited.

The vast majority of ecological and epidemiological studies of tick-borne pathogens involve collection of unfed ticks from the environment. In this view, our main aim was to evaluate the efficacy of a new method, where traditional flagging was enhanced by the use of dispersed CO2 into the white flannel.

Methods

Sweep and flag design

The sweep consists of a shaft and a flag. The shaft is constructed from a hollow aluminum tube, and the flag from white technical flannel. A JBL 500 g CO2 bottle with a CO2 solenoid regulator attached (both aquarium use, JBL Aquarium®, Germany) were fixed with plastic lock seals on the shaft. A silicone rubber hose was attached to the CO2 solenoid regulator; the hose was introduced through the aluminum shaft and connected to the flag. The rubber hose was pierced (to release CO2) and attached to the flag by sewing forming a network structure (Figure 1). The hose was made of bending-resistant silicone rubber with the inner diameter of 1 mm and the outer diameter of 2 mm with a wall thickness of 0.5 mm.

Figure 1
figure 1

Sweep CO 2 flag diagram.

Full size image

The flag surface area was 0.48 m2 (80 x 60 cm) to allow unrestricted passage across all types of vegetation. Two identical flags were made; one of them with CO2 and the other without CO2 (control).

Study area

Two hilly areas were chosen: Vultureni and Faget, both in Cluj county (Figure 2), according to preliminary results of sampling for the evaluation of the presence of tick-borne pathogens in Romania (manuscript under preparation). The habitats consisted in herbaceous vegetation alternating with small shrubs, located at the edge of woods, specific areas for ticks. The climate is moderate continental, influenced by the vicinity of the Apuseni Mountains and Atlantic influences from west of the country, in autumn and winter [13]. The study was conducted in spring, between the end of March and the end of April 2011, as tick abundance is higher in Northwestern Romania in this season [14]. The GPS was used to measure the distance.

Figure 2
figure 2

Field studies location (shaded area shows the flagging surface).

Full size image

Sampling procedure

On each collection site n = 30 samplings were performed (total 60 samplings in the two sites). Each sampling consisted in the simultaneous use of both flags, (with and without CO2), on 2 m wide adjacent areas, by two persons who had interchanged the sweep every fifty meters for the homogeneity of results. After each 5 m the flags were checked for ticks. All ticks were collected regardless their species and fixed in pure ethanol. Specific identification was performed using morphological keys [15] under a binocular microscope.

Determination of carbon dioxide

The CO2 concentration level on the flag canvas surface was measured using a portable CIRAS-2 Photosynthesis System equipped with a SRC-1 Soil Respiration Chamber (PP Systems International Inc®, USA). CO2 level was determined at a single time, but from several points of the flag (n = 20) according to instruction manual and recommendations [16]. The results were expressed in ppm as compared to the standard CO2 concentration of 393.71 ppm (reference data for 24.04.2011) [16].

Statistical analysis

The efficacy of the method was determined by counting the total number of ticks and separate developmental stage count, attached to the CO2 flag compared with the control (CO2-free flag). For statistical analysis, the values were compared in CHI-SQUARE TEST [17]. A p value of <0.05 was considered statistically significant. The relative risk (RR) is a ratio of the probability of the event occurring in the exposed group versus a non-exposed group [18].

Results

A total number of 4267 of ticks belonging to two species were collected in the 60 samplings: I. ricinus (n = 4081) and Dermacentor marginatus (n = 186).

I. ricinus accounted for 4081 tick captures (adults, nymphs and larvae) were collected in the 60 samplings (Table1). Of these, 2617 (64.1%) were adults, 1422 (34.9%) nymphs and 42 (1%) larvae. Using CO2 improved flag were captured 2411 (59%) ticks and 1670 (41%) without CO2.

Table 1 Number of questing Ixodes ricinus ticks collected by flagging with and without CO 2
Full size table

The statistical analysis revealed highly statistically significant (p < 0001) difference between the two variables in adults and nymphs, in both locations and overall; for larvae, the recorded statistical differences were not significant (Table2). Carbon dioxide flagging was more effective than CO2-free flagging, with average values of RR ranging between 1.4 and 1.6 for adults and nymphs.

Table 2 Statistical significance of tick collection efficacy using flagging with and without CO 2
Full size table

The addition of CO2 prompted a difference on the surface of the flag ranging between 756.5 and 1135.0 ppm with a mean value of 848.9 ppm.

Discussion

Flagging is the most widespread tick collection method. Over time, several improvements to this method were proposed [8] and now there is many types used: double walking flagging and double walking with baited flagging [19], walking flagging with a loose-fitting and white cotton flannel garment worn [20] and strip-flag method [21].

The successful hosts attack in Ixodes species expressed as the ability to adhere to a flannel flag is influenced by many factors: light and/or shadow, radiation heat (temperature), mechanical vibration of questing substrate, host odor, and CO2 concentration [22].

Chemical mediators also known as semiochemicals are as well important for behavioral patterns in ticks. These information-bearing compounds are secreted by animals into the external environment, and when recognized they trigger a specific behavioral response such as food location, sexual partner location or escape [23]. Semiochemicals are categorized into four major categories: (1) pheromones; (2) allomones; (3) kairomones; and (4) synomones [24].

Carbon dioxide acts like an attractant kairomone for ticks [25]. Experimentally, it acted as an attracting agent causing almost immediate activation in the soft ticks Ornithodoros coriaceus quiescent ticks [25]. Adults of Dermacentor andersoni respond also very well to stimulation with carbon dioxide. Garcia, 1965, described a system based on release of CO2 for the collection of D. andersoni. The system involved a piece of dry ice placed on a wire mesh platform in the desired area. The results indicate that the CO2 method is more sensitive for detection of adult ticks than is the conventional flagging technique [26]. Carbon dioxide (dry ice) trapping method was demonstrated to be effective in the collection of some tick species: I. ricinus[5], Amblyomma americanum[27–29] and A. hebraeum[30]. Our method is important in Europe as it enhances the capture of I. ricinus, the main vector of Borrelia burgdorferi s.l. and the tick-borne encephalitis (TBE) virus [31].

Our results are consistent with those cited above. The number of adults and nymphs of I. ricinus collected was significantly increased using CO2 enhanced blanket comparing with flagging without CO2. The lower number of larvae collected can be explained by the months of sampling, March-April, when larvae may be not fully active and by the quality of blanket, made by technical flannel, material which may not have reached the lower levels of the vegetation where larvae sit to quest.

These data show that the responsiveness to CO2 is enhanced during host-seeking periods of the life cycle and reduced at other times [32]. However, others [29] did not establish significant differences between flagging method with a strip blanket and CO2 traps or rabbits scent baits. The response time of ticks to host attachment was shown to be dependent on the tick species and CO2 concentration in the environment [33]. In Amblyomma maculatum A. americanum and Dermacentor variabilis, the groups preconditioned with low ambient CO2 (422 ppm) always produced response times of longer duration than ticks preconditioned to high ambient CO2 (956 ppm) [34].

The lack of statistical significance for D. marginatus between the two collecting methods compared in the present study might be caused by the major differences in the sample size. The small total number of D. marginatus collected (regardless the method used) can be explained by the typical area of this species which prefers biotopes characterized by xerophilic plant communities: dry pasture shrub communities, grazing black locust forests (Robinietum), forest-steppe or grikes (Quercetum pubescentis and Cometo Quercetum), margins of oak forests and bushy ridges between the fields and field paths [35]. Our study area is characterized by deforested hills and covered with low vegetation; predominant species in forest areas are hornbeam, birch, poplar, hazel, elm, ash and maple. Although D. marginatus is almost as widespread in Romania as I. ricinus, [36], the population density is significantly lower in most of the sampled localities [37]. Regarding seasonality, in Eastern Europe, D. marginatus is most numerous in February and March [38] and most of our sampling was done in April.

Flagging technique seems to work better for other species: Ixodes dammini[27], I. pacificus D. occidentalis and D. variabilis[32], I. rubicundus[39] or I. ricinus[40]. Four different methods of surveying were tested for D. variabilis and I. banksi and it was shown that the most successful was flagging, compared with carbon dioxide trapping, nest boxes and collection from hosts [41].

Concerning the temperature, I. persulcatus is a more cold-resistant tick than I. ricinus and it is more successful both in adhering to the flag and in remaining attached to it at two ranges: 6–10°C and 17–22°C [42]. In general a greater percentage of I. rubicundus displayed an appetence response at lower (12, 17 and 21°C) than at high (30°C) temperatures [39]. It is known that all life stages of I. ricinus are equipped to sense shifts in light intensity. This allows I. ricinus to use onset of darkness to trigger mobility when desiccation risk is reduced in nature [43]. The nymphs are stimulated to walk horizontally by humidity and host scent. When the atmosphere is sufficiently wet they are likely to walk towards odor secreted by host skin [44, 45]. The larvae of I. hirsti seem to be more sensitive to shade and heat, while they were unresponsive to CO2 concentration and host odor [46]. Radiation heat and shadowing caused the greatest percentage of I. rubicundus to display an appetence response; shadowing and radiation heat had the least effect on R. punctatus[22]. A single mechanical perturbation of the substratum caused a mean of 50% of I. rubicundus to display an appetence response. Constant mechanical perturbation resulted in a progressive decrease in the proportion of ticks reacting [22]. Host scent is known to initiate questing behavior in I. persulcatus I. ricinus and I. crenulatus. Both I. ricinus and I. crenulatus respond strongly to sheep wool [47, 48].

Entire-blanket flagging is a better sampling method for I. ricinus comparing with others variants of flagging or dragging. Significantly more nymphs and adults were caught by the entire-blanket versus strip-blanket flagging [49]. Flagging was 1.5–1.7 times as effective as dragging; impregnation of the cloths with different substances, like host odor, increased the efficacy by 2.4 (dragging) to 2.8 (flagging) times [39]. From several types of material used (i.e. cotton, woolen flannel, “molleton” - soft thick cotton, and toweling - spongecloth), the last was the best cloth type to optimize the number of ticks collected [36]. However, dry-ice-baited tick-traps is more effective for ticks with increased mobility, like A. americanum[27].

Our enhanced technique that combines, for the first time, classical flagging and carbon dioxide trapping methods improved significantly the ability of I. ricinus to adhere to flag blanket. By introducing CO2 in the white blanket we tried to simulate the time approach of a host to the tick. Sudden increase of the CO2 concentration in the air stimulates its vivacity and questing position, increasing the chance of attachment of ticks to the flag.

Conclusion

The study showed that the CO2 enhanced sweep flag increased the ability of I. ricinus (p < 0001) but not of D. marginatus to be attracted to the flag blanket.

References

  1. Guglielmone AA, Robbins RG, Apanaskevisch DA, Petney TN, Estrada-Pena A, Horak IG, Shao RF, Barker SC: The Argasidae, Ixodidae and Nuttalliellidae (Acari: Ixodida) of the world: a list of valid species name. Zootaxa. 2010, 2528: 1-28.

    Google Scholar 

  2. Keirans JE: Systematics of the Ixodida (Argasidae, Ixodidae, Nuttalliellidae): An overview and some problems. Tick Vector Biology, Medical and Veterinary Aspects. Edited by: Fivaz B, Petney T, Horak I. 1992, Springer Verlag, Berlin, 1-21.

    Chapter  Google Scholar 

  3. Oliver JH: Biology and systematics of ticks (Acari: Ixodida). Annu Rev Ecol Syst. 1989, 20: 397-430. 10.1146/annurev.es.20.110189.002145.

    Article  Google Scholar 

  4. Petney NT, Robbins RG, Guglielmone AA, Apanaskevich DA, Estrada-Peña A, Horak IG, Shao R: A Look at the World of Ticks. Progress in Parasitology. Edited by: Mehlhorn H. 2011, Springer Verlag, Berlin, 283-296.

    Chapter  Google Scholar 

  5. Capelli G, Ravagnan S, Montarsi F, Ciocchetta S, Cazzin S, Porcellato E, Babiker AM, Cassini R, Salviato A, Cattoli G, Otranto D: Occurrence and identification of risk areas of Ixodes ricinus-borne pathogens: a costeffectiveness analysis in north-eastern Italy. Parasite Vector. 2012, 5: 61-10.1186/1756-3305-5-61.

    Article  Google Scholar 

  6. Gray JS: A carbon dioxide trap for prolonged sampling of Ixodes ricinus L. populations. Exp Appl Acarol. 1985, 1: 35-44. 10.1007/BF01262198.

    Article  CAS  PubMed  Google Scholar 

  7. Braks M, Van der Giessen J, Kretzschmar M, Van Pelt W, Scholte EJ, Reusken C, Zeller H, Van Bortel W, Sprong H: Towards an integrated approach in surveillance of vector-borne diseases in Europe. Parasite Vector. 2011, 4: 192-10.1186/1756-3305-4-192.

    Article  Google Scholar 

  8. Carroll JF, Schmidtmann ET: Tick sweep: modification of the tick drag-flag method for sampling nymphs of the deer tick (Acari: Ixodidae). J Med Entomol. 1992, 29 (2): 352-355.

    Article  CAS  PubMed  Google Scholar 

  9. Jore S, Viljugrein H, Hofshagen M, Brun-Hansen H, Kristoffersen AB, Nygård K, Brun E, Ottesen P, Sævik BK, Ytrehus B: Multi-source analysis reveals latitudinal and altitudinal shifts in range of Ixodes ricinus at its northern distribution limit. Parasite Vector. 2011, 4: 84-10.1186/1756-3305-4-84.

    Article  Google Scholar 

  10. Jaenson TG, Jaenson DG, Eisen L, Petersson E, Lindgren E: Changes in the geographical distribution and abundance of the tick Ixodes ricinus during the past 30 years in Sweden. Parasite Vector. 2012, 5: 8-10.1186/1756-3305-5-8.

    Article  Google Scholar 

  11. Estrada-Peña A: Geostatistics as predictive tools to estimate Ixodes ricinus (Acari: Ixodidae) habitat suitability in the western Palearctic from AVHRR satellite imagery. Exp Appl Acarol. 1999, 23: 337-349. 10.1023/A:1006179318393.

    Article  Google Scholar 

  12. Randolph SE: Tick ecology: processes and patterns behind the epidemiological risk posed by ixodid ticks as vectors. Parasitol. 2004, 129: S37-S65. 10.1017/S0031182004004925.

    Article  Google Scholar 

  13. Trusca V, Alecu M: Romania General Facts. Romania’s Third National Communication on Climate Change under the United Nations Framework Convention on Climate Change. 2005, Grue & Hornstrup, Holstebro, 21-65.

    Google Scholar 

  14. Chiţimia L: [Ecology of Ixodidae in Southwestern Romania] [in Romanian]. PhD Thesis. 2006, Universitatea de Ştiinţe Agricole şi Medicină Veterinară a Banatului, Timişoara, 283-

    Google Scholar 

  15. Feider Z: [Fauna of the Popular Republic of Romania. Volume 5/2. Acaromorpha, Suprafamily Ixodoidea] [in Romanian]. 1965, Editura Academiei Republicii Populare Române, Bucureşti

    Google Scholar 

  16. Conway T, Tans P: NOAA/ESRL. www.esrl.noaa.gov/gmd/ccgg/trends/. Accessed 30 november 2011

  17. Snedecor GW, Cochran WG: Statistical Methods. 1989, Iowa State University Press, Ames, 8

    Google Scholar 

  18. Localio AR, Margolis DJ, Berlin JA: Relative risks and confidence intervals were easily computed indirectly from multivariable logistic regression. J Clin Epidemiol. 2007, 60 (9): 874-882. 10.1016/j.jclinepi.2006.12.001.

    Article  PubMed  Google Scholar 

  19. Fernández-Ruvalcaba M, Jesus F, De La Torre P, Cordoba-Juarez G, García-Vazquez Z, Rosario-Cruz R, Saltijeral-Oaxaca J: Animal bait effect on the recovery of Boophilus microplus larvae from experimentally infested grass in Morelos, Mexico. Parasitol Latinoam. 2003, 58: 54-58.

    Article  Google Scholar 

  20. Chapman ES, Siegle TE: A novel method for tick retrieval reveals northern migration of Amblyomma americanum into Pike County, IL, USA. Int J Acarol. 2000, 26 (4): 391-393. 10.1080/01647950008684215.

    Article  Google Scholar 

  21. Gray JS, Lohan G: The development of a sampling method for the tick Ixodes ricinus and its use in a redwater fever area. Ann Appl Biol. 1982, 101 (3): 421-427. 10.1111/j.1744-7348.1982.tb00842.x.

    Article  Google Scholar 

  22. Fourie LJ, Snyman A, Kok DJ, Horak IG, Van Zyl JM: The appetence behaviour of two South African paralysis-inducing ixodid ticks. Exp Appl Acarol. 1993, 17: 921-930. 10.1007/BF02328069.

    Article  CAS  PubMed  Google Scholar 

  23. Sonenshine DE: Pheromones and other semiochemicals of ticks and their use in tick control. Parasitology. 2004, 129: S405-S425. 10.1017/S003118200400486X.

    Article  CAS  PubMed  Google Scholar 

  24. Evenden ML, Judd GJR, Borden JH: A synomone imparting distinct sex pheromone communication channels for Choristonuera rosaceana (Harris) and Pandemis limitata (Robinson) (Lepidoptera: Tortricidae). Chemoecology. 1999, 9: 73-80. 10.1007/s000490050036.

    Article  CAS  Google Scholar 

  25. Garcia R: Carbon dioxide as an attractant for certain ticks (Acarina: Argasidae and Ixodidae). Ann Entomol Soc Am. 1962, 55 (5): 605-606.

    Article  CAS  Google Scholar 

  26. Garcia R: Collection of Dermacentor andersoni (stiles) with carbon dioxide and its application in studies of Colorado tick fever virus. Am J Trop Med Hyg. 1965, 14 (6): 1090-1093.

    Google Scholar 

  27. Ginsberg HS, Ewing CP: Comparison of flagging, walking, trapping, and collecting from hosts as sampling methods for northern deer ticks, Ixodes dammini, and lone-star ticks, Amblyomma americanum (Acari: Ixodidae). Exp Appl Acarol. 1989, 7: 313-322. 10.1007/BF01197925.

    Article  CAS  PubMed  Google Scholar 

  28. Kinzer DR, Presley SM, Hair JA: Comparative efficiency of flagging and carbon dioxide-baited sticky traps for collecting the lone star tick, Amblyomma americanum (Acarina: Ixodidae). J Med Entomol. 1990, 27 (5): 750-755.

    Article  CAS  PubMed  Google Scholar 

  29. Schulze TL, Jordan RA, Hung RW: Biases associated with several sampling methods used to estimate abundance of Ixodes scapularis and Amblyomma americanum (Acari: Ixodidae). J Med Entomol. 1997, 34 (6): 615-623.

    Article  CAS  PubMed  Google Scholar 

  30. Anderson RB, Scrimgeour GJ, Kaufman WR: Responses of the tick, Amblyomma hebraeum (Acari: Ixodidae), to carbon dioxide. Exp Appl Acarol. 1998, 22: 667-681. 10.1023/A:1006006721358.

    Article  Google Scholar 

  31. Dautel H, Kahl O: Ticks (Acari: Ixodoidea) and their medical importance in the urban environment. Proceedings of the Third International Conference on Urban Pests: 19–22 July 1999. Edited by: Robinson WH, Rettich F, Rambo GW. 1999, , Prague, 73-82.

    Google Scholar 

  32. Li X, Dunley JE: Optimal sampling and spatial distribution of Ixodes pacificus, Dermacentor occidentalis and Dermacentor variabilis ticks (Acari: Ixodidae). Exp Appl Acarol. 1998, 22: 233-248. 10.1023/A:1006018432064.

    Article  CAS  PubMed  Google Scholar 

  33. Gray JS: Studies on the larval activity of the tick Ixodes ricinus L. in Co. Wicklow, Ireland. Exp Appl Acarol. 1985, 1: 307-316. 10.1007/BF01201570.

    Article  CAS  PubMed  Google Scholar 

  34. Holscher KH, Gearhart HL, Barker RW: Electrophysiological responses of three tick species to carbon dioxide in the laboratory and field. Ann Entomol Soc Am. 1980, 73 (3): 288-292.

    Article  Google Scholar 

  35. Nosek J: The ecology, bionomics, behaviour and public health importance of Dermacentor marginatus and D. reticulatus ticks. Wiad Parazyt. 1972, XVIII (4-5-6): 721-725.

    Google Scholar 

  36. Mihalca AD, Dumitrache MO, Magdaş C, Gherman CM, Domşa C, Mircean V, Ghira IV, Pocora V, Ionescu DT, Sikó Barabási S, Cozma V, Sándor AD: Synopsis of the hard ticks (Acari: Ixodidae) of Romania with update on host associations and geographical distribution. Exp Appl Acarol. 2012, 10.1007/s10493-012-9566-5.

    Google Scholar 

  37. Mihalca AD, Gherman CM, Magdas V, Dumitrache MO, Győrke A, Sándor AD, Domşa C, Oltean M, Mircean V, Mărcuţan DI, D’Amico G, Păduraru AO, Cozma V: Ixodes ricinus is the dominant questing tick in forest habitats in Romania: the results from a countrywide dragging campaign. Exp Appl Acarol. 2012, 10.1007/s10493-012-9568-3.

    Google Scholar 

  38. Hornok S: Allochronic seasonal peak activities of Dermacentor and Haemaphysalis spp. under continental climate in Hungary. Vet Parasitol. 2009, 163: 366-369. 10.1016/j.vetpar.2009.03.048.

    Article  PubMed  Google Scholar 

  39. Fourie LJ, Van Der Lingen F, Kok DJ: Improvement of field sampling methods for adult Karoo paralysis ticks, Ixodes rubicundus (Acari: Ixodidae), through addition of host odour. Exp Appl Acarol. 1995, 19: 93-101. 10.1007/BF00052549.

    Article  CAS  PubMed  Google Scholar 

  40. Vassallo M, Pichon B, Cabaret J, Figureau C, Perez-Eid C: Methodology for sampling questing nymphs of Ixodes Ricinus (Acari: Ixodidae), the principal vector of lyme disease in Europe. J Med Entomol. 2000, 37 (3): 335-339. 10.1603/0022-2585(2000)037[0335:MFSQNO]2.0.CO;2.

    Article  CAS  PubMed  Google Scholar 

  41. Keaney P: The Effectiveness Of Various Trapping Techniques In Collecting Ixodes scapularis and Other Species of Ticks. 1994

    Google Scholar 

  42. Uspensky I: Ability of successful attack in two species of ixodid ticks (Acari Ixodidae) as a manifestation of their aggressiveness. Exp Appl Acarol. 1993, 17: 673-683. 10.1007/BF00058507.

    Article  CAS  PubMed  Google Scholar 

  43. Perret JL, Guerin PM, Diehl PA, Vlimant M, Gern L: Darkness induces mobility, and saturation deficit limits questing duration, in the tick Ixodes ricinus. J Exp Biol. 2003, 206: 1809-1815. 10.1242/jeb.00345.

    Article  PubMed  Google Scholar 

  44. Crooks E, Randolph SE: Walking by Ixodes ricinus ticks: intrinsic and extrinsic factors determine the attraction of moisture or host odour. J Exp Biol. 2006, 209: 2138-2142. 10.1242/jeb.02238.

    Article  PubMed  Google Scholar 

  45. Greenfield BPJ: Environmental parameters affecting tick (Ixodes ricinus) distribution during the summer season in Richmond Park, London. Bioscience Horizons. 2011, 0 (0): 1-9.

    Google Scholar 

  46. Oorebeek M, Sharrad T, Kleindorfer S: What attracts larval Ixodes hirsti (Acari: Ixodidae) to their host?. Parasitol Res. 2009, 104: 623-628. 10.1007/s00436-008-1238-3.

    Article  PubMed  Google Scholar 

  47. Lees AD: The behaviour and physiology of ticks. Acarol. 1969, 11 (3): 397-410.

    CAS  Google Scholar 

  48. Elizarov YA, Vasewta AA: A distant orientation of blood-sucking ixodid ticks to the host’s attractant factors. (in Russian). Parazit Sb. 1976, 10: 136-141.

    Google Scholar 

  49. Tack W, Madder M, De Frenne P, Vanhellemont M, Gruwez R, Verheyen K: The effects of sampling method and vegetation type on the estimated abundance of Ixodes ricinus ticks in forests. Exp Appl Acarol. 2011, 54: 285-292. 10.1007/s10493-011-9444-6.

    Article  PubMed  Google Scholar 

Download references

Acknowledgements

This research was financed by project PCCE 7/2010 by CNCSIS.

Author information

Authors and Affiliations

  1. Department of Parasitology and Parasitic Diseases, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, Calea Mănăştur 3-5, Cluj-Napoca, 400372, Romania

    Călin M Gherman, Andrei D Mihalca, Mirabela O Dumitrache, Adriana Györke & Vasile Cozma

  2. Department of Plant and Environmental Protection, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, Calea Mănăştur 3-5, Cluj-Napoca, 400372, Romania

    Ioan Oroian & Mignon Sandor

Authors
  1. Călin M Gherman
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Andrei D Mihalca
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Mirabela O Dumitrache
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Adriana Györke
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Ioan Oroian
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Mignon Sandor
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Vasile Cozma
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Andrei D Mihalca.

Additional information

Competing interests

The authors declare that they have no competing interests.

Authors’ contributions

GCM wrote the manuscript, performed flagging. MAD concept idea, performed the flagging. DMO identified the ticks. GA statistical analysis. OI measurement of CO2. SM measurement of CO2. CV team coordinator. All authors read and approved the final manuscript.

Authors’ original submitted files for images

Rights and permissions

Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution License ( https://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

Gherman, C.M., Mihalca, A.D., Dumitrache, M.O. et al. CO2 flagging - an improved method for the collection of questing ticks. Parasites Vectors 5, 125 (2012). https://doi.org/10.1186/1756-3305-5-125

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/1756-3305-5-125

Keywords

Parasites & Vectors

ISSN: 1756-3305

Contact us