Oecologia

, Volume 162, Issue 1, pp 217–225 | Cite as

Altitudinal patterns of tick and host abundance: a potential role for climate change in regulating tick-borne diseases?

Global Change Ecology - Original Paper

Abstract

The impact of climate change on vector-borne infectious diseases is currently controversial. In Europe the primary arthropod vectors of zoonotic diseases are ticks, which transmit Borrelia burgdorferi sensu lato (the agent of Lyme disease), tick-borne encephalitis virus and louping ill virus between humans, livestock and wildlife. Ixodes ricinus ticks and reported tick-borne disease cases are currently increasing in the UK. Theories for this include climate change and increasing host abundance. This study aimed to test how I. ricinus tick abundance might be influenced by climate change in Scotland by using altitudinal gradients as a proxy, while also taking into account the effects of hosts, vegetation and weather effects. It was predicted that tick abundance would be higher at lower altitudes (i.e. warmer climates) and increase with host abundance. Surveys were conducted on nine hills in Scotland, all of open moorland habitat. Tick abundance was positively associated with deer abundance, but even after taking this into account, there was a strong negative association of ticks with altitude. This was probably a real climate effect, with temperature (and humidity, i.e. saturation deficit) most likely playing an important role. It could be inferred that ticks may become more abundant at higher altitudes in response to climate warming. This has potential implications for pathogen prevalence such as louping ill virus if tick numbers increase at elevations where competent transmission hosts (red grouse Lagopus lagopus scoticus and mountain hares Lepus timidus) occur in higher numbers.

Keywords

Ixodes ricinus Louping ill virus Lyme disease Deer Elevation 

References

  1. Bolton D (1980) The computation of equivalent potential temperature. Mon Weather Rev 108:1046–1053CrossRefGoogle Scholar
  2. Burri C, Cadenas FM, Douet V, Moret J, Gern L (2007) Ixodes ricinus density and infection prevalence of Borrelia burdorferi sensu lato along a north-facing altitudinal gradient in the Rhone valley (Switzerland). Vector Borne Zoonotic Dis 7:50–58CrossRefPubMedGoogle Scholar
  3. Cadenas FM, Rais O, Jouda F, Douet V, Humair P-F, Moret J, Gern L (2007) Phenology of Ixodes ricinus and infection with Borrelia burgdorferi sensu lato along and north- and south-altitudinal gradient on Chaumont mountain, Switzerland. J Med Entomol 44:683–693CrossRefGoogle Scholar
  4. Daniel M (1993) Influence of the microclimate on the vertical distribution of the tick Ixodes ricinus (L.) in Central Europe. Acarologia 34:105–113Google Scholar
  5. Daniels TJ, Falco RC, Fish D (2000) Estimating population size and drag sampling efficiency for the blacklegged tick (Acari: Ixodidae). J Med Entomol 37:357–363CrossRefPubMedGoogle Scholar
  6. Elston DA, Moss R, Boulinier T, Arrowsmith C, Lambin X (2001) Analysis of aggregation, a worked example: numbers of ticks on red grouse chicks. Parasitology 122:563–569. doi:10.1017/S0031182001007740 CrossRefPubMedGoogle Scholar
  7. Gilbert L, Jones LD, Hudson PJ, Gould EA, Reid HW (2000) The role of small mammals in the persistence of louping-ill virus: field survey and co-feeding studies. Med Vet Entomol 14:278–283CrossRefGoogle Scholar
  8. Gray JS (1998) The ecology of ticks transmitting Lyme borreliosis. Exp Appl Acarol 22:249–258CrossRefGoogle Scholar
  9. Gray JS, Lohan G (1982) The development of a sampling method for the tick Ixodes ricinus and its use in a redwater fever area. Ann Appl Biol 101:421–427CrossRefGoogle Scholar
  10. Health Protection Scotland (2009) http://www.documents.hps.scot.nhs.uk/giz/10-year-tables/lyme.pdf (last accessed March 2009)
  11. Hester AJ, Gordon IJ, Baillie GJ, Tappin E (1999) Foraging behaviour of sheep and red deer within natural heather grass mosaics. J Appl Ecol 36:133–146CrossRefGoogle Scholar
  12. Hudson PJ (1992) Grouse in space and time. Game Conservancy Trust, FordingbridgeGoogle Scholar
  13. Jones LD, Gaunt M, Hails RS, Laurenson K, Hudson PJ, Reid H, Henbest P, Gould EA (1997) Transmission of louping-ill virus between infected and uninfected ticks co-feeding on mountain hares. Med Vet Entomol 11:172–176CrossRefPubMedGoogle Scholar
  14. Jouda F, Perret J, Gern L (2004) Ixodes ricinus density and distribution and prevalence of Borrelia burgdorferi sensu lato infection along an altitudinal gradient. J Med Entomol 41:162–169CrossRefPubMedGoogle Scholar
  15. Kirby AD, Smith AA, Benton TG, Hudson PJ (2004) Rising burden of immature sheep ticks (Ixodes ricinus) on red grouse (Lagopus lagopus scoticus) chicks in the Scottish uplands. Med Vet Entomol 18:67–70CrossRefPubMedGoogle Scholar
  16. Laurenson MK, Norman RA, Gilbert L, Reid HW, Hudson PJ (2003) Identifying disease reservoirs in complex systems: mountain hares as reservoirs of ticks and louping-ill virus, pathogens of red grouse. J Anim Ecol 72:177–185CrossRefGoogle Scholar
  17. Lindgren E, Gustafson R (2001) Tick-borne encephalitis in Sweden and climate change. Lancet 358:16–18CrossRefPubMedGoogle Scholar
  18. Lindgren E, Tälleklint L, Polfeldt T (2000) Impact of climatic change on the northern latitude limit and population density of the disease-transmitting European tick Ixodes ricinus. Environ Health Perspect 108:119–123CrossRefPubMedGoogle Scholar
  19. MacLeod J (1935) Ixodes ricinus in relation to its physical environment. II. The factors governing survival and activity. Parasitology 27:123–144CrossRefGoogle Scholar
  20. Perret JL, Guigoz E, Rais O, Gern L (2000) Influence of saturation deficit and termperature on Ixodes ricinus tick questing activity in a Lyme borreliosis-endemic area (Switzerland). Parasitol Res 86:554–557CrossRefPubMedGoogle Scholar
  21. Randolph SE (2001) The shifting landscape of tick-borne zoonoses: tick-borne encephalitis and Lyme borreliosis in Europe. Phil Trans R Soc Lond B 356:1045–1056CrossRefGoogle Scholar
  22. Randolph SE (2004) Tick ecology: processes and patterns behind the epidemiological risk posed by ixodid ticks as vectors. Parasitology 129:S1–S29CrossRefGoogle Scholar
  23. Randolph SE (2009) Perspectives on climate change impacts on infectious diseases. Ecology 90:927–931CrossRefPubMedGoogle Scholar
  24. Randolph SE, Storey K (1999) Impact of microclimate on immature tick-rodent host interactions (Acari: Ixodidae): implications for parasite transmission. J Med Entomol 36:741–748PubMedGoogle Scholar
  25. Reid HW (1975) Experimental infection of the red grouse with louping-ill virus (Flavivirus group). I. The viraemia and antibody response. J Comp Pathol 85:231–235CrossRefPubMedGoogle Scholar
  26. Scharlemann JPW, Johnson PJ, Smith AA, Macdonald DW, Randolph SE (2008) Trends in ixodid tick abundance and distribution in Great Britain. Med Vet Entomol 22:238–247CrossRefPubMedGoogle Scholar
  27. Watts EJ (2007) The role of host and habitat spatial heterogeneity in the distribution of ticks and tick-borne diseases in the Scottish uplands. Ph.D. thesis, University of AberdeenGoogle Scholar
  28. Wilson K (2009) Climate change and the spread of infectious ideas. Ecology 90:901–902CrossRefPubMedGoogle Scholar
  29. Zeman P, Beneš C (2006) A tick-borne encephalitis ceiling in Central Europe has moved upwards during the last 30 years: possible impact of global warming? Int J Med Microbiol 293(Suppl 37):48–54Google Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.Macaulay Land Use Research InstituteAberdeenUK

Personalised recommendations