Modulatory effect of cattle on risk for Lyme disease.To determine the effect of cattle on the risk for Lyme disease Lyme disease, a nonfatal bacterial infection that causes symptoms ranging from fever and headache to a painful swelling of the joints. The first American case of Lyme's characteristic rash was documented in 1970 and the disease was first identified in a cluster at , we compared the prevalence of spirochete spirochete Any of an order (Spirochaetales) of spiral-shaped bacteria. Some are serious pathogens for humans, causing such diseases as syphilis, yaws, and relapsing fever. Spirochetes are gram-negative (see gram stain) and motile. infection in questing vector ticks collected from a pasture with low-intensity cattle grazing with the prevalence in those collected from a site on which no cattle grazed. The presence of cattle limited the prevalence of Borrelia burgdorferi Borrelia burg·dor·fe·ri n. A spirochete causing Lyme disease in humans. Borrelia burgdorferi The spirochete agent of Lyme disease, which contains several outer membrane proteins and a highly immunogenic flagellar s.l., but not B. miyamotoi, in vector ticks. The reintroduction of traditional, nonintensive agriculture in central Europe Central Europe is the region lying between the variously and vaguely defined areas of Eastern and Western Europe. In addition, Northern, Southern and Southeastern Europe may variously delimit or overlap into Central Europe. may help reduce risk for Lyme disease. ********** The tick Ixodes ricinus, which transmits the spirochete agent of Lyme disease, is abundant in the ecotone e·co·tone n. A transitional zone between two communities containing the characteristic species of each. [eco- + Greek tonos, tension, tone; see tone. at a forest's edge. The brushy vegetation there provides a suitable microclimate microclimate Climatic condition in a relatively small area, within a few feet above and below the Earth's surface and within canopies of vegetation. Microclimates are affected by such factors as temperature, humidity, wind and turbulence, dew, frost, heat balance, for these vector ticks as well as food and cover for the animals that serve as hosts for the ticks' subadult stages. Of those, rodents and particular passerine passerine Any perching bird. All passerines belong to the largest order of birds, Passeriformes, and have feet specialized for holding onto a horizontal branch (perching). The passerine foot has three forward-directed toes and one backward-directed toe. birds serve as reservoirs for the agent of Lyme disease (1-8). Other animals, such as domestic ungulates ungulates, ungulata animals with hooves; cattle, sheep, goat, pig, horse and many wild and other domesticated species. , serve as hosts for the tick but fail to support the pathogen. These animals exert a zooprophylactic effect on the transmission cycle by diverting ticks from feeding on reservoir-competent hosts. Any tick feeding on these hosts fails to acquire spirochetes and, thereby, fails to contribute to transmission (9,10). In addition, infected ticks may lose the pathogen when feeding on such incompetent hosts (11-14). The ecotone constitutes the focus of transmission, and persons may acquire numerous vector ticks when passing through such a site. The local composition of vertebrate animals serving as hosts to vector ticks determines the risk for infection at that site. Recently, the European Union European Union (EU), name given since the ratification (Nov., 1993) of the Treaty of European Union, or Maastricht Treaty, to the European Community and the United Nations Educational, Scientific and Cultural Organization (UNESCO UNESCO: see United Nations Educational, Scientific, and Cultural Organization. UNESCO in full United Nations Educational, Scientific and Cultural Organization ) instituted programs to limit the growth of brush and subsequent reforestation Reforestation The reestablishment of forest cover either naturally or artificially. Given enough time, natural regeneration will usually occur in areas where temperatures and rainfall are adequate and when grazing and wildfires are not too frequent. of uncultivated land. These programs specifically target the ecotonal habitat that developed ubiquitously in Europe when cultivating marginal land was considered too labor-intensive and costly. Toward this end, traditional farming methods are being reimplemented. Domestic ungulates, for example, are being introduced into the ecotone for landscape management. By grazing or browsing on scrub brush and saplings, these animals help maintain open landscapes and simultaneously enhance biodiversity. Although domestic animals may alter the contours of the ecotone, the effect of their presence on the risk for human infection by the agent of Lyme disease has not been defined. To determine whether the presence of domestic ungulates may reduce risk for human Lyme disease, we compared the prevalence of spirochetal infection in ticks taken from an ecotonal cattle pasture to that in a site in which no cattle were permitted to graze. In addition, we determined the prevalence of the different Lyme disease genospecies in these ticks and that of a distantly related spirochete. Materials and Methods The study site, [approximately equal to] 2 [km.sup.2,] is located near the town of Lembach, in the northern Vosges region of France, at the floodplain floodplain, level land along the course of a river formed by the deposition of sediment during periodic floods. Floodplains contain such features as levees, backswamps, delta plains, and oxbow lakes. of the Sauer River. It is part of the Pfalzer Wald--Vosges du Nord biosphere biosphere, irregularly shaped envelope of the earth's air, water, and land encompassing the heights and depths at which living things exist. The biosphere is a closed and self-regulating system (see ecology), sustained by grand-scale cycles of energy and of reserve of UNESCO. Scottish Highland cattle Highland cattle Noun a breed of cattle with shaggy reddish-brown hair and long horns were introduced there in 1999 for low-intensity grazing. About 250 cattle are allowed to graze in the floodplain year-round and are rotated on grazing patches enclosed by electric fencing on a total area of [approximately equal to] 200 [km.sup.2]. The fence does not constitute a barrier to other vertebrates, such as hedgehogs, foxes, or deer. On the cattle pasture and at a site 10 m outside the pasture, questing ticks were sampled by passing a flannel flag over the vegetation; ticks were preserved in 80% ethanol. We sampled the sites twice, in early May and early June 2005. Ticks were collected from 3 distinct areas within and 2 areas outside the pasture site. Both sites are separated by a path [approximately equal to] 4 m wide. Microscopy was used to identify stage and species of all ticks. To detect and identify the various spirochetes that may be present in these ticks, the opisthosoma The opisthosoma is the posterior portion of the arachnids body behind the prosoma (cephalothorax). The number of segments and appendages on the opisthosoma vary. In general, appendages are absent or reduced, although in horseshoe crabs they persist as large plate-like limbs, called of each was opened, the contained mass of soft tissue was dissected out and placed in physiologic saline, and DNA DNA: see nucleic acid. DNA or deoxyribonucleic acid One of two types of nucleic acid (the other is RNA); a complex organic compound found in all living cells and many viruses. It is the chemical substance of genes. was extracted as described previously (15). Borrelia Borrelia A genus of spirochetes that have a unique genome composed of a linear chromosome and numerous linear and circular plasmids. Borreliae are motile, helical organisms with 4–30 uneven, irregular coils, and are 5–25 micrometers long and 0. genospecies were detected and characterized by amplifying and sequencing a 600-nt fragment of the gene encoding the 16S rRNA by nested PCR PCR polymerase chain reaction. PCR abbr. polymerase chain reaction Polymerase chain reaction (PCR) (15). Each resulting sequence was compared with sequences of the homologous homologous /ho·mol·o·gous/ (ho-mol´ah-gus) 1. corresponding in structure, position, origin, etc. 2. allogeneic. ho·mol·o·gous adj. 1. gene fragment representing each of the validated spirochete genospecies. The following sequences served for comparison: GenBank accession nos. X85196 and X85203 for B. burgdorferi s.s.; X85190, X85192, and X85194 for B. afzelii; X85193, X85199, and M64311 for B. garinii; X98228 and X98229 for B. lusitaniae; X98232 and X98233 for B. valaisiana; AY147008 for B. spielmanii; and AY253149 for B. miyamotoi. A complete match, permitting no more than 2 nt changes, was required. Results To determine the effect of the presence of cattle on the prevalence of spirochetal infection in vector ticks, we sampled questing ticks within a fenced site where cattle grazed, examined them individually for spirochetal DNA by PCR and compared the resulting prevalence to that in ticks sampled from at least 10 m beyond the fence. Spirochetes infected [approximately equal to] 4x as many nymphs and [approximately equal to] 6x as many adults outside the enclosure as within (Table) (Fisher exact test, p<0.0001 for either developmental stage). The variance between different samples taken within the pasture site and the variance between samples taken outside the pasture were considerably smaller than the variance between the pasture and the nonpasture site. Fewer questing ticks harbored spirochetes where cattle were present than where they were absent. We then determined whether the presence of cattle affects a spirochetal genospecies more than others. Amplified spirochetal DNA derived from each infected tick was sequenced and the genospecies determined by comparison with published sequences. Where cattle were present, virtually no nymphal nymph n. 1. Greek & Roman Mythology Any of numerous minor deities represented as beautiful maidens inhabiting and sometimes personifying features of nature such as trees, waters, and mountains. 2. or adult ticks were infected by B. valaisiana (Fisher exact test, p = 0.006, p = 0.05, respectively; Table). The prevalence of B. lusitaniae in ticks sampled on the cattle pasture was about one tenth the prevalence in ticks sampled outside the pasture (Fisher exact test, p = 0.025 in nymphs, p = 0.0025 in adults). B. garinii infected about one twentieth as many nymphal ticks and about one eighth as many adult ticks where cattle were present compared with the nonpasture site (Fisher exact test, p<0.0001 for either developmental stage). Whereas the prevalence of B. afzelii in nymphal ticks appeared to be not significantly affected by the presence of cattle, its prevalence in adult ticks was reduced to approximately one quarter (Fisher exact test, p = 0.0019). Too few ticks infected by B. burgdorferi s.s. or B. spielmanii were sampled to permit comparison. In contrast to the prevalence of Lyme disease spirochetes, the prevalence of B. miyamotoi, an ixodid-borne member of relapsing fever relapsing fever Infectious disease with recurring fever, caused by several spirochetes of the genus Borrelia, transmitted by lice, ticks, and bedbugs. Onset is sudden, with high fever, which breaks within a week with profuse sweating. Symptoms return about a week later. spirochetes, was similar, regardless of the presence of cattle. We conclude that the presence of cattle appears to reduce the prevalence of Lyme disease spirochetes in vector ticks but appears not to influence that of a distantly related spirochete. Discussion A vertebrate animal originally was said to be zooprophylactic if its presence in an endemic site serves to divert invertebrate invertebrate (ĭn'vûr`təbrət, –brāt'), any animal lacking a backbone. The invertebrates include the tunicates and lancelets of phylum Chordata, as well as all animal phyla other than Chordata. vectors of a human pathogen from feeding on people (16). The concept was extended for Lyme disease to include more specific diversionary effects on the force of transmission of the pathogen, including diversion of the vector tick from feeding on potential reservoir hosts, transportation of vector ticks away from the venue of transmission, or elimination of infection from a previously infected tick (11). Lizards, for example, fail to support Lyme disease spirochetes, and the prevalence of infection in questing vector ticks appears reduced where such hosts are abundant (2,9). Ticks may detach from birds in nonsultable habitats. Zooprophylaxis may affect the prevalence of infection in vector ticks by various factors. Wild ungulates are generally thought to contribute to risk for Lyme disease, mainly by supporting the population of vector ticks. Indeed, adult I. dammini (or scapularis) ticks in the northeastern United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. appear to preferably feed on white-tailed deer white-tailed deer or Virginia deer Common reddish brown deer (Odocoileus virginianus), an important game animal found alone or in small groups from southern Canada to South America. (17). Because they serve as definitive host for the tick, density of deer correlates with tick abundance (18,19). Reduction or elimination of deer on islands or their exclusion by electric fences has resulted in fewer subadult ticks questing in subsequent years; the density of adult ticks, however, has declined only slowly (20-23). In contrast, a simulation model indicates that the density of ticks may be more sensitive to the availability of hosts for the subadult stages than to that of hosts for adult ticks (24). In Europe, diverse medium-sized and large mammals, such as hares, hedgehogs, and foxes, constitute alternative hosts for adult ticks (25-27). As a result, any association between the abundance of vector ticks and the density of deer may be less profound in Europe than in eastern North America North America, third largest continent (1990 est. pop. 365,000,000), c.9,400,000 sq mi (24,346,000 sq km), the northern of the two continents of the Western Hemisphere. . Domestic as well as wild ungulates exert a powerful zooprophylactic effect on Lyme disease spirochetes because they are incompetent for these pathogens. Not only do noninfected ticks that feed on these mammals fail to acquire spirochetes, but also infected ticks lose their infection during the course of such a bloodmeal (10,12,28,29). The sensitivity to the bacteriolytic bac·te·ri·ol·y·sis n. pl. bac·te·ri·ol·y·ses Dissolution or destruction of bacteria. bac·te activity of the complement pathway may determine the incompetence of a host (30). Cattle support the feeding of numerous ticks of all stages (10) and thereby divert subadult vector ticks from feeding on reservoir-competent hosts. A simulation model indicated that the availability of incompetent hosts for subadult tick stages would reduce prevalence of infection (24). Our observation that questing nymphal and adult ticks collected on a cattle pasture were less likely to be infected by Lyme disease spirochetes than were vector ticks collected outside the pasture supports this model. In addition, cattle and other domestic ungulates may modify the ecotonal vegetation by their grazing. This would render the microclimate more arid and, thereby, less suitable for the survival of ticks. Indeed, during equal time periods, we collected approximately half as many questing ticks where cattle were present as we did where cattle were absent (1 tick every 4 minutes vs. 2 minutes, respectively). Grazing cattle may also deplete de·plete v. 1. To use up something, such as a nutrient. 2. To empty something out, as the body of electrolytes. reservoir-competent rodents and birds foraging in this ecotone of their food source and of cover from predators. By reducing the availability of potential reservoir hosts, additional subadult stages are diverted to feed on incompetent domestic ungulates. Whether the effect of cattle on the prevalence of spirochete infection in questing vector ticks results from the inability of cattle to support the pathogen or from their effect on tick habitat and reservoir rodents remains to be determined. In addition to their parasitologic effects, certain zooprophylactic animals may modify the ecotonal landscape in ways that affect transmission of the agent of Lyme disease. Although the presence of cattle appears to suppress the prevalence of the various genospecies of Lyme disease spirochetes, that of B. miyamotoi is not affected. It is more closely related to spirochetes that cause relapsing fever than to spirochetes that cause Lyme disease (31). No disease relationship has yet been demonstrated for this microbe microbe /mi·crobe/ (mi´krob) a microorganism, especially a pathogenic one such as a bacterium, protozoan, or fungus.micro´bialmicro´bic mi·crobe n. . B. miyamotoi spirochetes infect [approximately equal to] 2%-5% of questing nymphal or adult I. ricinus--like ticks, regardless of location (15,32). The prevalence of Lyme disease spirochetes, on the other hand, varies from zero to [approximately equal to] 50%, depending on the local composition of reservoir populations. Our observation that the prevalence of B. miyamotoi is insensitive to the presence of cattle corroborates reports on transovarial transmission Transovarial transmission occurs in certain arthropod vectors as they transmit disease-causing bacteria from parent arthropod to offspring arthropod. For instance, Rickettsia rickettsii (32) and suggests that this spirochete may cycle solely within the vector population. The European Union and UNESCO support various policies for the deintensification of agriculture. The European Union's Biodiversity Action Plan ''This article is about a conservation biology topic. For other uses of BAP, see BAP (disambiguation). A Biodiversity Action Plan (BAP) is an internationally recognized program addressing threatened species and habitats, which is designed to protect and restore biological for Agriculture, for example, recognizes that traditional nonintensive agriculture, as it was practiced for centuries until only a few decades ago, maintained an enormous species variety in wild and domestic flora and fauna (33). By encouraging extensive agricultural practices, such programs aim to prevent further abandonment of marginal farmland and the subsequent development of scrub brush and forests that support relatively few species. Management of previous fallow land as low-intensity pastures for robust varieties of cattle, sheep, goats, horses, or pigs helps maintain or reestablish not only open landscapes but also high nature value habitats (high biodiversity achieved by extensive farming). Our finding that the prevalence of Lyme disease spirochetes in questing vector ticks is significantly reduced on such pastures suggests that enhanced biodiversity may also contribute directly to human health. Conclusions derived from a mathematical model similarly suggest that a species-rich composition of vertebrates that serve as hosts for vector ticks would decrease the prevalence of spirochete-infected ticks by diluting the effect of reservoir-competent hosts (34). Efforts aimed at extensive landscape management may help to reduce risk for Lyme disease in central Europe. We conclude that cattle appear to modulate risk for Lyme disease by reducing the prevalence of Lyme disease spirochetes in vector ticks; they do not, however, influence prevalence of a distantly related spirochete. Our observations were conducted in a high nature-value habitat that included an extensively managed cattle pasture. In addition to the direct parasitologic effects, certain zooprophylactic animals may modify the landscape in ways that affect the transmission of Lyme disease spirochetes. Removal of ground-covering vegetation may reduce the force of transmission of this pathogen by reducing local rodent density, thereby diverting vector ticks to reservoir-incompetent cattle. Zooprophylaxis may include environmental modification. Our finding that the prevalence of B. miyamotoi is insensitive to the presence of cattle suggests that this spirochete may be perpetuated differently than are Lyme disease spirochetes. Extensive landscape management in central Europe may help reduce risk for Lyme disease. Acknowledgments We thank Daniela Schlee, Mandy Potter, and Udo Bischoff for excellent technical assistance. This study was supported by grant Ma 942/10-2 from the Deutsche Forschungsgemeinschaft. Dr Richter is an associate research scientist at the medical school Charite Universitatsmedizin Berlin. Her research interests focus on the immunologic and molecular interface of the host-vector-pathogen relationship in the epizootiology of tickborne diseases. Dr Matuschka is a university professor at the medical school Charite Universitatsmedizin Berlin and head of the parasitology Parasitology The scientific study of parasites and of parasitism. Parasitism is a subdivision of symbiosis and is defined as an intimate association between an organism (parasite) and another, larger species of organism (host) upon which the parasite is laboratory. His research focuses on transmission cycles of zoonotic diseases Zoonotic diseases Diseases caused by infectious agents that can be transmitted between (or are shared by) animals and humans. This can include transmission through the bite of an insect, such as a mosquito. Mentioned in: West Nile Virus . References (1.) Donahue JG, Piesman J, Spielman A. Reservoir competence of white-footed mice for Lyme disease spirochetes. Am J Trop Med Hyg. 1987;36:92-6. (2.) Matuschka F-R, Fischer P, Heiler M, Richter D, Spielman A. Capacity of European animals as reservoir hosts for the Lyme disease spirochete. J Infect Dis. 1992;165:479-83. (3.) Matuschka F-R, Endepols S, Richter D, Spielman A. Competence of urban rats as reservoir hosts for Lyme disease spirochetes. J Med Entomol. 1997;34:489-93. (4.) Matuschka F-R, Allgower R, Spielman A, Richter D. Characteristics of garden dormice that contribute to their capacity as reservoirs for Lyme disease spirochetes. Appl Environ Microbiol. 1999;65:707-11. (5.) Olsen B, Jaenson TG, Bergstrom S. Prevalence of Borrelia burgdorferi sensu lato-infected ticks on migrating birds. Appl Environ Microbiol. 1995;61:3082-7. (6.) Richter D, Spielman A, Komar N, Matuschka F-R. Competence of American robins as reservoir hosts for Lyme disease spirochetes. Emerg Infect Dis. 2000;6:133-8. (7.) Talleklint L, Jaenson TG. Transmission of Borrelia burgdorferi s.l. from mammal reservoirs to the primary vector of Lyme borreliosis Lyme borreliosis Another name for Lyme disease. Mentioned in: Lyme Disease , Ixodes ricinus (Acari: Ixodidae), in Sweden. J Med Entomol. 1994;31:880-6. (8.) Ginsberg HS, Buckley PA, Balmforth MG, Zhioua E, Mitra S, Buckley FG. Reservoir competence of native North American birds <onlyinclude> This list of North American birds is a comprehensive listing of all the bird species known from the North American continent north of Mexico. </onlyinclude> for the Lyme disease spirochete, Borrelia burgdorferi. J Med Entomol. 2005;42:445-9. (9.) Lane RS, Loye JE. Lyme disease in California: Interrelationship in·ter·re·late tr. & intr.v. in·ter·re·lat·ed, in·ter·re·lat·ing, in·ter·re·lates To place in or come into mutual relationship. in of Ixodes pacificus (Acari: Ixodidae), the western fence lizard Noun 1. western fence lizard - common western lizard; seen on logs or rocks blue-belly, Sceloporus occidentalis, swift fence lizard - spiny lizard often seen basking on fences in the United States and northern Mexico (Sceloporus occidentalis), and Borrelia burgdorferi. J Med Entomol. 1989;26:272-8. (10.) Matuschka F-R, Eiffert H, Ohlenbusch A, Richter D, Schein E, Spielman A. Transmission of the agent of Lyme disease on a subtropical sub·trop·i·cal adj. Of, relating to, or being the geographic areas adjacent to the Tropics. subtropical Adjective of the region lying between the tropics and temperate lands island. Trop Med Parasitol. 1994;45:39-44. (11.) Matuschka F-R, Spielman A. Loss of Lyme disease spirochetes from Ixodes ricinus ticks feeding on European blackbirds. Exp Parasitol. 1992;74:151-8. (12.) Matuschka F-R, Heiler M, Eiffert H, Fischer P, Lotter H, Spielman A. Diversionary role of hoofed game in the transmission of Lyme disease spirochetes. Am J Trop Med Hyg. 1993;48:693-9. (13.) Telford SR, Mather TN, Moore SI, Wilson ML, Spielman A. Incompetence of deer as reservoirs of the Lyme disease spirochete. Am J Yrop Med Hyg. 1988;39:105-9. (14.) Jaenson TG, Talleklint L. Incompetence of roe deer as reservoirs of the Lyme borreliosis spirochete. J Med Entomol. 1992;29:813-7. (15.) Richter D, Schlee DB, Matuschka F-R. Relapsing fever-like spirochetes infecting European vector tick of Lyme disease agent. Emerg Infect Dis. 2003;9:697-701. (16.) Russell PF, West LS, Manwell RD, MacDonald G. Practical malariology malariology Rare. the study of malaria. — malariologist, n. See also: Disease and Illness , 2nd ed. London: Oxford University Press; 1963. (17.) Piesman J, Spielman A, Etkind P, Ruebush TK, Juranek DD. Role of deer in the epizootiology of Babesia microti Babesia mi·cro·ti n. A species of Babesia that causes babesiosis in humans, usually transmitted by the northern deer tick. Babesia microti in Massachusetts, USA. J Med Entomol. 1979;15:537-40. (18.) Rand PW, Lubelczyk C, Lavigne GR, Elias S, Holman MS, Lacombe EH, et al. Deer density and the abundance of Ixodes scapularis Ixodes scapularis Deer tick A tick with a 2-yr life cycle, and 3 feeding seasons; the cycle begins in spring with soil deposition of fertilized eggs; by summer, larvae emerge and imbibe a blood meal from small vertebrates–eg, white-footed mouse– (Acari: Ixodidae). J Med Entomol. 2003;40:179-84. (19.) Wilson ML, Adler GH, Spielman A. Correlation between abundance of deer and that of the deer tick deer tick n. Any of several ticks of the genus Ixodes that are parasitic on deer and other animals and transmit the infectious agents of febrile diseases, such as Lyme disease. , Ixodes dammini Ixodes dam·mi·ni n. A species of Ixodes that is a vector of Lyme disease and human babesiosis in the United States. tick (Acari: Ixodidae). Ann Entomol Soc Am. 1985;78:172-6. (20.) Daniels TJ, Fish D. Effect of deer exclusion on the abundance of immature Ixodes scapularis (Acari: Ixodidae) parasitizing small and medium-sized mammals. J Med Entomol. 1995;32:5-11. (21.) Rand PW, Lubelczyk C, Holman MS, Lacombe EH, Smith RP. Abundance of Ixodes scapularis (Acari: Ixodidae) after the complete removal of deer from an isolated offshore island, endemic for Lyme disease. J Med Entomol. 2004;41:779-84. (22.) Stafford KC. Reduced abundance of Ixodes scapularis (Acari: Ixodidae) with exclusion of deer by electric fencing. J Med Entomol. 1993;30:986-96. (23.) Wilson ML, Telford SR, Piesman J, Spielman A. Reduced abundance of immature Ixodes dammini (Acari: Ixodidae) following elimination of deer. J Med Entomol. 1988;25:224-8. (24.) Van Buskirk J, Ostfeld RS. Controlling Lyme disease by modifying the density and species composition of tick hosts. Ecol Appl. 1995;5:1133-40. (25.) Sreter T, Szell Z, Varga I. Ectoparasite ec·to·par·a·site n. A parasite that lives on the surface or exterior of the host organism, such as an ectophyte or an ectozoon. ec infestations of red foxes (Vulpes vulpes Vulpes vulpes see red fox. ) in Hungary. Vet Parasitol. 2003;115:349-54. 26. Talleklint L, Jaenson TGT TGT Target TGT Ticket Granting Ticket (Windows 2000 Kerberos security) TGT Target Corp (stock symbol) TGT Turbine Gas Temperature TGT TDRSS Ground Terminal TGT Tank Gunnery Trainer TGT Target Tracker . Infestation infestation /in·fes·ta·tion/ (-fes-ta´shun) parasitic attack or subsistence on the skin and/or its appendages, as by insects, mites, or ticks; sometimes used to denote parasitic invasion of the organs and tissues, as by helminths. of mammals by Ixodes ricinus ticks (Acari: Ixodidae) in south-central Sweden. Exp Appl Acarol. 1997;21:755-71. (27.) Walter G, Liebisch A. Untersuchungen zur Biologie und Verbreitung von Zecken (Ixodoidea, Ixodidae) in Norddeutschland. III. Ixodes ricinus (Linnaeus 1758). Z Angew Zool. 1980;67:449-76. (28.) Jaenson TGT, Talleklint L. Incompetence of roe deer as reservoirs of the kyme borreliosis spirochete. J Med Entomol. 1992;29:813-7. (29.) Telford SR, Mather TN, Moore SI, Wilson ML, Spielman A. Incompetence of deer as reservoirs of the Lyme disease spirochete. Am J Trop Med Hyg. 1988;39:105-9. (30.) Kurtenbach K, De Michelis S, Etti S, Schafer SM, Sewell H-S, Brade V, et al. Host association of Borrelia burgdorferi sensu lato--the key role of host complement. Trends Microbiol. 2002; 10:74-9. (31.) Fukunaga M, Koreki Y. The flagellin flagellin /fla·gel·lin/ (flah-jel´in) a protein of bacterial flagella; it is composed of subunits in several-stranded helical arrangement. gene of Borrelia miyamotoi sp. nov. and its phylogenetic phy·lo·ge·net·ic adj. 1. Of or relating to phylogeny or phylogenetics. 2. Relating to or based on evolutionary development or history. relationship among Borrelia species. FEMS FEMS Federation of European Microbiological Societies FEMS Federation of European Materials Societies FEMS Fabrication Engineering Management System FEMS Facility Equipment Maintenance System (PMEL/TMDE) Microbiol Lett. 1995;134:255-8. (32.) Scoles GA, Papero M, Beati L, Fish D. A relapsing fever group spirochete transmitted by Ixodes scapularis ticks. Vector Borne Zoonotic Zoonotic A disease which can be spread from animals to humans. Mentioned in: Zoonosis Dis. 2001;1:21-34. (33.) Biodiversity action plan for agriculture. Communication from the commission to the council and the European parliament, vol. III; 2001 [cited 2006 Oct]. Commission of the European communities, Brussels, Belgium [online]. Available from http://ec.europa.eu/agriculture/envir/biodiv/162_en.pdf (34.) LoGiudice K, Ostfeld RS, Schmidt KA, Keesing F. The ecology of infectious disease Infectious disease A pathological condition spread among biological species. Infectious diseases, although varied in their effects, are always associated with viruses, bacteria, fungi, protozoa, multicellular parasites and aberrant proteins known as prions. : Effects of host diversity and community composition on Lyme disease risk. Proc Natl Acad Sci USA. 2003;100:567-71. Dania Richter * and Franz-Rainer Matuschka * * Charite Universitatsmedizin Berlin, Berlin, Germany Address for correspondence: Dania Richter, Abteilung Parasitologie, Institut fur Pathologie, Charite Universitatsmedizin Berlin, Malteserstrasse 74-100, 12249 Berlin, Germany; email: drichter@charite.de
Table. Prevalence of spirochetes in questing nymphal and adult
Ixodes ricinus ticks sampled in and outside a cattle pasture,
France *
Ticks examined
Cattle % [+ or -]
in site Stage No. Infected SD
Present Nymph 238 5.5 5.8
Adult 136 5.9 3.7
Absent Nymph 95 22.1 5.8
Adult 236 40.3 2.3
% Ticks infected by Borrelia
Cattle
in site Stage B. afzeli B. garinii B. valaisiana
Present Nymph 2.9 0.4 0
Adult 3.7 ([dagger]) 1.5 0
Absent Nymph 5.3 9.5 4.2 ([dagger])
Adult 13.6 ([dagger]) 12.7 3.0 ([double
dagger])
% Ticks infected by Borrelia
Cattle B. burgdorferi
in site Stage s.s. B.lusitaniae
Present Nymph 0.4 0.4
Adult 0 0.7
Absent Nymph 0 4.2
Adult 0.4 7.6
% Ticks infected by Borrelia
Cattle
in site Stage B. spielmanii B. miyamotoi
Present Nymph 0 1.3
Adult 0 0.7
Absent Nymph 0 0
Adult 1.3 3.0
* SD, standard deviation.
([dagger]) Includes a tick coinfected with B. garinii.
([double dagger]) Includes 2 ticks coinfected with S. garinii.
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