A mass occurrence of the European pigeon tick Argas reflexus (Acari, Argasidae) in Gdańsk Joanna N. Izdebska 1, Sławomira Fryderyk 1, Bartłomiej Kentzer 2 1 Laboratory of Parasitology and General Zoology, Department of Invertebrate Zoology, University of Gdańsk, Piłsudskiego 46, 81-378 Gdynia, Poland; e-mail: izdebska@ocean.ug.gda.pl 2 Museum of Amber - a branch of the Gdansk History Museum, Foregate Complex of the Dluga street, Targ Węglowy 26, 80-836 Gdańsk, Poland Abstract Argas reflexus (Acari, Argasidae), the European pigeon tick, is the Argasidae species most frequently found in Poland. Information on its occurrence is relatively sparse, however, having been reported from only a few localities, mainly in central and southern Poland. In the north of the country it has only been found once before, at Gdańsk-Wrzeszcz. The article reports a mass occurrence of these soft ticks in a recently renovated, listed building in the Old Town of Gdańsk in autumn and winter 2006. For lack of their typical host (Feral Pigeon), the ticks attacked humans, frequently causing allergic reactions. As a result, pest control treatments were undertaken with a variety of biocides and repellents, including powerful acaricides. Incidents of this kind may become more frequent as a result of the widespread use of devices to prevent pigeons from settling in and on residential and public buildings. Introduction Argas reflexus (Fabricius, 1794) (European pigeon tick) (Fig. 1, 2) is a soft tick living in West, South and Central Europe (Fillipova 1966, Buczek 1993, Khoury and Maroli 2004; Siuda and Siuda 2005). Of the three Argasidae (Acari, Ixodida) species recorded in Poland it is the one most frequently mentioned in the Polish subject literature (e.g., Siuda 1993). Nonetheless, information on its occurrence is rather scarce. It has been recorded at a fairly small number of localities, mostly in the central and southern parts of the country, and on one occasion in the north, at Gdańsk-Wrzeszcz (Wegner 1973). This article reports on a recent large-scale occurrence of A. reflexus in a listed building in the Old Town of Gdańsk. A. reflexus is a species inhabiting nest holes and niches, its principal and typical host being the Feral Pigeon. It has been occasionally recorded in other birds, e.g. Crag 47
Martin (Ptyonoprogne rupestris), Jackdaw (Corvus monedula), Little Owl (Athene noctua) and house sparrow (Passer domesticus) (Fillipova 1966). Large-scale parasitism of pigeons by soft ticks may cause considerable loss of blood, with consequent debilitation and loss of body mass; nestlings are particularly susceptible (Filippova 1966; Siuda 1993). There are a number of reports of these ticks attacking humans (e.g., Wegner 1973; Buczek 1991, Buczek and Solarz 1993; Wójcik et al. 2001; Khoury and Maroli 2004; Śpiewak et al. 2006). A mass occurrence of Argas reflexus in Gdańsk In the autumn and winter of 2006 there was a mass occurrence of pigeon ticks in a recently renovated, listed building in the Old Town of Gdańsk. The largest numbers were recorded on the sixth and seventh floors, i.e. at heights of 20.21 28.68 m above street level, where the humidity was 60-70% and the temperature 19-20 C. As a result of numerous reconstructions of this building, the thickness of the walls at this location varies considerably, from 1 to 3 m, and it is more than likely that there are spaces between the walls providing concealment for the ticks. The mites were extremely numerous on the outer and inner walls of the building, and also on the floors (Fig. 3) on one occasion more than ten thousand specimens were collected (Tab. 1, Fig. 4, 5). As people in the building were attacked, often suffering allergic reactions as a result, it was decided to invoke pest control measures. Several treatment attempts were undertaken to eradicate the soft ticks. The final and most successful one, which left only single ticks still alive, was made in December 2006 using long-action insecticides registered in Poland: K-Othrine, Alfacet, Facam, Quickbayt (emulsions/aqueous solutions), ABC (powder), Aqua PY + Croto (hot fog), Aerofum (DDVP; cold fog), Steridial (disinfectant). That treatment was carried out at an ambient temperature of 8-12 C and was repeated until successful, that is, for nearly two weeks. It was applied in several stages, using a combination of the above pesticides (pyrenoids and organophosphorus compounds) with biocidal and repellent properties, in the form of hot and cold fogs. Depending on the site to be treated, a hand or powered sprayer and a powder applicator were used; all the relevant safety precautions were strictly observed. Following the treatments a large number of dead ticks and flies were found, also in sites difficult of access, where the pesticides had not been applied directly (data from the pest control report PUH Cargofum 381/2006). Table 1. Argas reflexus number of one test collected in December of 2006, in the Old Town of Gdańsk ARGAS REFLEXUS DATE OF COLLECTING TOTAL STAGE AND SEX 14.12.2006 28.12.2006 Female 421 680 1101 Male 283 376 659 Nymph 2980 4068 7048 Larve 615 1106 1721 Summary 4299 6230 10529 48
Mass occurrences of pigeon ticks causes and effects Attacks of pigeon ticks on humans are fairly frequent, especially when the tick population has risen excessively, or when no birds are available, for example, when a pigeon loft is removed or destroyed (e.g., Wegner 1973, Siuda et al. 1982, Buczek 1991, Buczek and Solarz 1993, Śpiewak et al. 2006). The bites are painful, and the resultant itching can last quite a long time. Pigeon tick feeding on humans may lead to stress, allergic reactions, poisoning, skin swelling and rash, fever, weakness, nausea, giddiness and headaches, faster breathing, raised heart rate, and fainting; in extreme cases, pigeon tick bites may be life-threatening. The ticks themselves are also reservoirs and vectors of many pathogenic organisms (e.g., Siuda 1993, Kleine-Tebbe et al. 1999, Khoury and Maroli 2004, Haag-Wackernagel 2005, Siuda and Siuda 2005). Despite the relative frequency of such attacks, there are not many literature reports detailing mass occurrences of pigeon ticks, especially in premises frequented to a greater or lesser extent by humans. In Poland these ticks have hitherto been found in synanthropic sites, e.g. in the roof spaces and lofts of churches, office and residential buildings, not to mention dovecotes and pigeon lofts, all localities frequented by Feral Pigeons, the principal hosts of these ticks (e.g., Buczek 1991, Siuda 1993, Śpiewak et al. 2006). The mass occurrence of A. reflexus reported here took place in a building visited by very many people, especially during the daytime. One reason for the extremely large numbers of ticks in this particular case was probably the complete refurbishment and conversion of a very old, listed building. Previously, some parts of the building would have been inhabited by large numbers of Feral Pigeons, hence the presence of their common parasites, A. reflexus. Active from early spring until winter, these ticks attack their hosts at night. Adult ticks are resistant to low temperatures and, in addition, can withstand starvation for more than a year; their nymphs can go without feeding for as long as three years. Hence, they could well have survived the period of the building s refurbishment and conversion. However, with the prolongation of starvation, the hungry ticks began to leave their concealment, even during the day, spreading out in all directions and entering the public areas of the building. The upshot: attacks on humans. 49
Feral Pigeons are becoming an ever more serious problem in large conurbations. Undemanding as regards nest site selection, they can, given favourable conditions, nest and produce young throughout the year. That is why they have become the most numerous bird species in the centres of most large cities and many smaller ones, often causing damage to listed buildings and monuments. Moreover, they harbour pathogenic organisms dangerous to both humans and domestic animals (Haag-Wackernagel and Śpiewak 2004, Khoury and Maroli 2004). In turn, one of their most common parasites is Argas reflexus. Mass occurrences of this tick species and its attacks on humans, similar to the case described, may recur with greater frequency as a consequence of the widespread use of devices to prevent pigeons from settling in and on residential and public buildings. References Buczek A. 1991. Charakterystyka Argas (A.) reflexus (Fabricius, 1794) (Acari: Ixodida: Argasidae)-pospolitego pasożyta na Górnym Śląsku. Wiad. Parazytol. 37: 375-380. Buczek A. 1993. Morfological variability of Argas (Argas) reflexus (Fabricius, 1794) (Acari: Ixodida: Argasidae). Females and males from a Silesian population. Z. Angew Zool. 4: 409-419. Buczek A., Solarz K. 1993. Atakowanie ludzi przez Argas reflexus (Ixodida, Argasidae) groźne pasożyty człowieka i zwierząt. Pol. Tyg. 48: 238-239. Filippowa N.A. 1966. Argasowyje kleszczy (Argasidae). Fauna SSSR. Paukoobraznyje, 4, 3, Nauka, Moskwa: passim. Haag-Wackernagel D., Śpiewak, R. 2004. Human infestation by pigeon fleas (Ceratophyllus columbae) from feral pigeons. Ann.Agric. Environ. Med. 11: 343 346. Haag-Wackernagel D. 2005. Parasites from feral pigeons as a health hazard for humans. Ann. Appl. Biol. 147: 203-210. Khoury C., Maroli M. 2004. La zecca del piccione Argas reflexus (Acari: Argasidae) ed i rischi per la salute umana. Ann Ist Super Sanitŕ. 40: 427-432. Kleine-Tebbe J., Herold. D., Dautel H., Vater G., Heinatz A., Schroder I., Haut A., Mittag, M., Lange, I., Rytter, M., Haustein, U.F. 1999. The pigeon tick (Argas reflexus): Severe alleric bite reactions in humans. Zentralb. Bakteriol. 289: 754-755. Siuda K. 1993. Kleszcze Polski (Acari, Ixododa). Część II. Systematyka i rozmieszczenie. Monogr. Parazytol. PTP, Warszawa: passim. Siuda K. 2006. Charakterystyka kleszczy (Ixodida) o znaczeniu medycznym w Polsce. In. Skotarczak B. (ed.), Biologia molekularna patogenów przenoszonych przez kleszcze. Wyd. Lekarskie PZWL,Warszawa: 33-44. Siuda, K., Jarosz, Z., Norek, L. 1982. Przypadek zaatakowania strażaków-hejnalistów Kościoła Mariackiego w Krakowie przez obrzeżki polskie Argas (Argas) polonicus Siuda, Hoogstraal, Cliford et Wassef, 1979 (Acarina, Ixodides, Argasidae). Wiad. Parazytol. 27: 57-62. Siuda, K., Siuda, I. 2005. Kleszcze (Acari: Ixodida) i ich znaczenie medyczne. W: Majkowska-Wojciechowska B. (ed.), Alergia na roztocze. Mediton, Łódź: 105-122. Śpiewak, R., Lundberg, M., Johansson, S.G., Buczek A. 2006. Allergy to pigeon tick (Argas reflexus) in Upper Silesia, Poland. Ann. Agric. Environ. Med. 13: 107-112. Wegner, Z. 1973. Dwa nowe przypadki atakowania ludzi przez pasożytnicze roztocze ptasie (Acarina: Argassidae i Dermanyssidae) w Polsce. Wiad. Parazytol. 19: 187-191. Wójcik, A.R, Wasielewski, L., Żbikowska, E., Grygon-Franckiewicz, B. 2001. Argas reflexus (Fabricius,1794) przyczyną akarozy u ludzi. Wiad. Parzytol. 47: 61-65. 50
Fig. 1. Argas reflexus dorsal view (photo by J.N. Izdebska) Fig. 2. Argas reflexus ventral view (photo by J.N. Izdebska) Fig. 3. The pigeon tick were extremely numerous on the outer and inner walls of the building, and also on the floors (photo by B. Kentzer) Fig. 4. On one occasion more than ten thousand specimens of Argas reflexus were collected (photo by B. Kentzer)