Spatial epidemiology of eastern equine encephalitis in Florida

International Journal of Health Geographics

Thomas R Unnasch³  James H Anderson²  Rebecca W Loraamm²  Lillian M Stark¹  Joni A Downs²  Patrick T Vander Kelen³ 

[1] Florida Department of Health, Bureau of Laboratories-Tampa, 3602 Spectrum Blvd, Tampa, FL, 33612, USA;Department of Geography, Environment, and Planning, University of South Florida, 4202 E. Fowler Ave, Tampa, FL, 33620, USA;Global Health Infectious Disease Research Program, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA

关键词: Euclidean distance;    Compositional analysis;    Spatial epidemiology;    GIS;    Eastern equine encephalitis;   

Others  :  821442
DOI  :  10.1186/1476-072X-11-47

 received in 2012-08-03, accepted in 2012-10-20,  发布年份 2012

【 摘 要 】

Background

Eastern Equine Encephalitis virus (EEEV) is an alphavirus with high pathogenicity in both humans and horses. Florida continues to have the highest occurrence of human cases in the USA, with four fatalities recorded in 2010. Unlike other states, Florida supports year-round EEEV transmission. This research uses GIS to examine spatial patterns of documented horse cases during 2005–2010 in order to understand the relationships between habitat and transmission intensity of EEEV in Florida.

Methods

Cumulative incidence rates of EEE in horses were calculated for each county. Two cluster analyses were performed using density-based spatial clustering of applications with noise (DBSCAN). The first analysis was based on regional clustering while the second focused on local clustering. Ecological associations of EEEV were examined using compositional analysis and Euclidean distance analysis to determine if the proportion or proximity of certain habitats played a role in transmission.

Results

The DBSCAN algorithm identified five distinct regional spatial clusters that contained 360 of the 438 horse cases. The local clustering resulted in 18 separate clusters containing 105 of the 438 cases. Both the compositional analysis and Euclidean distance analysis indicated that the top five habitats positively associated with horse cases were rural residential areas, crop and pastureland, upland hardwood forests, vegetated non-forested wetlands, and tree plantations.

Conclusions

This study demonstrates that in Florida tree plantations are a focus for epizootic transmission of EEEV. It appears both the abundance and proximity of tree plantations are factors associated with increased risk of EEE in horses and therefore humans. This association helps to explain why there is are spatially distinct differences in the amount of EEE horse cases across Florida.

【 授权许可】

   
2012 Vander Kelen et al.; licensee BioMed Central Ltd.

【 图 表 】

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【 参考文献 】

• [1]Villari P, Spielman A, Komar N, McDowell M, Timperi RJ: The economic burden imposed by a residual case of eastern encephalitis. Am J Trop Med Hyg 1995, 52:8-13.
• [2]Eastern Equine Encephalitis, Epidemiology and Geographic Distributionhttp://www.cdc.gov/easternequineencephalitis/tech/epi.html webcite
• [3]Scott TW, Weaver SC: Eastern equine encephalomyelitis virus: epidemiology and evolution of mosquito transmission. Adv Virus Res 1989, 37:277-328.
• [4]Crans WJ: Bloodmeal preference studies with New Jersey mosquitoes. Proceedings of the New Jersey Mosquito Extermination Association 1962, 49:120-126.
• [5]Howard JJ, Morris CD, Emord DE, Grayson MA: Epizootiology of eastern equine encephalitis virus in upstate New York, USA. VII. Virus surveillance 1978–85, description of 1983 outbreak, and series conclusions. J Med Entomol 1988, 25:501-514.
• [6]Crans WJ, McNelly J, Schulze TL, Main A: Isolation of eastern equine encephalitis virus from Aedes sollicitans during an epizootic in southern New Jersey. J Am Mosq Control Assoc 1986, 2:68-72.
• [7]Day JF, Stark LM: Eastern equine encephalitis transmission to emus (Dromaius novaehollandiae) in Volusia County, Florida: 1992 through 1994. J Am Mosq Control Assoc 1996, 12:429-436.
• [8]Cupp EW, Klingler K, Hassan HK, Viguers LM, Unnasch TR: Transmission of eastern equine encephalomyelitis virus in central Alabama. Am J Trop Med Hyg 2003, 68:495-500.
• [9]Vander Kelen PT, Downs JA, Burkett-Cadena ND, Ottendorfer CL, Hill K, Sickerman S, Hernandez J, Jinright J, Hunt B, Lusk J, et al.: Habitat Associations of Eastern Equine Encephalitis Transmission in Walton County Florida. J Med Entomol 2012, 49:746-756.
• [10]Center for Disease Control and Prevention: 2012 Case Definitions: Nationally Notifiable Conditions Infectious and Non-Infectious Case. 2012. [Atlanta, GA]
• [11]Letson GW, Bailey RE, Pearson J, Tsai TF: Eastern equine encephalitis (EEE): a description of the 1989 outbreak, recent epidemiologic trends, and the association of rainfall with EEE occurrence. Am J Trop Med Hyg 1993, 49:677-685.
• [12]Bigler WJ, Lassing E, Buff E, Lewis AL, Hoff GL: Arbovirus surveillance in Florida: wild vertebrate studies 1965–1974. J Wildl Dis 1975, 11:348-356.
• [13]United States Department of Agriculture: 2010 Summary of Eastern Equine Encephalitis Cases In The United States. 2011.
• [14]Ostfeld RS, Glass GE, Keesing F: Spatial epidemiology: an emerging (or re-emerging) discipline. Trends Ecol Evol 2005, 20:328-336.
• [15]Lian M, Warner RD, Alexander JL, Dixon KR: Using geographic information systems and spatial and space-time scan statistics for a population-based risk analysis of the 2002 equine West Nile epidemic in six contiguous regions of Texas. Int J Health Geogr 2007, 6:42. BioMed Central Full Text
• [16]Lambin EF, Tran A, Vanwambeke SO, Linard C, Soti V: Pathogenic landscapes: interactions between land, people, disease vectors, and their animal hosts. Int J Health Geogr 2010, 9:54. BioMed Central Full Text
• [17]Krefis AC, Schwarz NG, Nkrumah B, Acquah S, Loag W, Oldeland J, Sarpong N, Adu-Sarkodie Y, Ranft U, May J: Spatial analysis of land cover determinants of malaria incidence in the ashanti region, ghana. PLoS One 2011, 6:e17905.
• [18]Eisen RJ, Eisen L: Spatial modeling of human risk of exposure to vector-borne pathogens based on epidemiological versus arthropod vector data. J Med Entomol 2008, 45:181-192.
• [19]Kitron U: Landscape ecology and epidemiology of vector-borne diseases: tools for spatial analysis. J Med Entomol 1998, 35:435-445.
• [20]Guerra MA, Walker ED, Kitron U: Canine surveillance system for Lyme borreliosis in Wisconsin and northern Illinois: geographic distribution and risk factor analysis. Am J Trop Med Hyg 2001, 65:546-552.
• [21]Eisen RJ, Lane RS, Fritz CL, Eisen L: Spatial patterns of Lyme disease risk in California based on disease incidence data and modeling of vector-tick exposure. Am J Trop Med Hyg 2006, 75:669-676.
• [22]Kiffner C, Zucchini W, Schomaker P, Vor T, Hagedorn P, Niedrig M, Ruhe F: Determinants of tick-borne encephalitis in counties of southern Germany, 2001–2008. Int J Health Geogr 2010, 9:42. BioMed Central Full Text
• [23]LaBeaud AD, Gorman AM, Koonce J, Kippes C, McLeod J, Lynch J, Gallagher T, King CH, Mandalakas AM: Rapid GIS-based profiling of West Nile virus transmission: defining environmental factors associated with an urban-suburban outbreak in Northeast Ohio, USA. Geospat Health 2008, 2:215-225.
• [24]Brownstein JS, Rosen H, Purdy D, Miller JR, Merlino M, Mostashari F, Fish D: Spatial analysis of West Nile virus: rapid risk assessment of an introduced vector-borne zoonosis. Vector Borne Zoonotic Dis 2002, 2:157-164.
• [25]Ruiz MO, Walker ED, Foster ES, Haramis LD, Kitron UD: Association of West Nile virus illness and urban landscapes in Chicago and Detroit. Int J Health Geogr 2007, 6:10. BioMed Central Full Text
• [26]Diuk-Wasser MA, Brown HE, Andreadis TG, Fish D: Modeling the spatial distribution of mosquito vectors for West Nile virus in Connecticut, USA. Vector Borne Zoonotic Dis 2006, 6:283-295.
• [27]Nakhapakorn K, Tripathi NK: An information value based analysis of physical and climatic factors affecting dengue fever and dengue haemorrhagic fever incidence. Int J Health Geogr 2005, 4:13. BioMed Central Full Text
• [28]Reisen WK: Landscape epidemiology of vector-borne diseases. Annu Rev Entomol 2010, 55:461-483.
• [29]Moncayo AC, Edman JD, Finn JT: Application of geographic information technology in determining risk of eastern equine encephalomyelitis virus transmission. J Am Mosq Control Assoc 2000, 16:28-35.
• [30]Shaman J: Amplification due to spatial clustering in an individual-based model of mosquito-avian arbovirus transmission. Trans R Soc Trop Med Hyg 2007, 101:469-483.
• [31]Wimberly MC, Hildreth MB, Boyte SP, Lindquist E, Kightlinger L: Ecological niche of the 2003 west nile virus epidemic in the northern great plains of the United States. PLoS One 2008, 3:e3744.
• [32]Gatton ML, Kelly-Hope LA, Kay BH, Ryan PA: Spatial-temporal analysis of Ross River virus disease patterns in Queensland, Australia. Am J Trop Med Hyg 2004, 71:629-635.
• [33]United States Department of Agriculture: 2007 Census of Agriculture Vol 1. Washington: Government Printing Office; 2009:1-639.
• [34]Armstrong PM, Andreadis TG, Anderson JF, Stull JW, Mores CN: Tracking eastern equine encephalitis virus perpetuation in the northeastern United States by phylogenetic analysis. Am J Trop Med Hyg 2008, 79:291-296.
• [35]Florida Department of Transportation: Florida Land Use, Cover And Forms Classification System. 1999.
• [36]Ross WA, Kaneene JB: A case–control study of an outbreak of Eastern Equine Encephalomyelitis in Michigan (USA) equine herds in 1991. Prev Vet Med 1995, 24:157-170.
• [37]Day JF, Shaman J: Using hydrologic conditions to forecast the risk of focal and epidemic arboviral transmission in peninsular Florida. J Med Entomol 2008, 45:458-465.
• [38]Shaman J, Day JF, Stieglitz M, Zebiak S, Cane M: Seasonal forecast of St. Louis encephalitis virus transmission, Florida. Emerg Infect Dis 2004, 10:802-809.
• [39]Inventory FNA: Guide to the natural communities of Florida 2010 edn. 2010. [Tallahassee, FL]
• [40]Weaver SC: Host range, amplification and arboviral disease emergence. Arch Virol Suppl 2005, 19:33-44.
• [41]Brault AC, Powers AM, Chavez CL, Lopez RN, Cachon MF, Gutierrez LF, Kang W, Tesh RB, Shope RE, Weaver SC: Genetic and antigenic diversity among eastern equine encephalitis viruses from North, Central, and South America. Am J Trop Med Hyg 1999, 61:579-586.
• [42]Sabattini MS, Daffner JF, Monath TP, Bianchi TI, Cropp CB, Mitchell CJ, Aviles G: Localized eastern equine encephalitis in Santiago del Estero Province, Argentina, without human infection. Medicina (B Aires) 1991, 51:3-8.
• [43]Aguilar PV, Robich RM, Turell MJ, O'Guinn ML, Klein TA, Huaman A, Guevara C, Rios Z, Tesh RB, Watts DM, et al.: Endemic eastern equine encephalitis in the Amazon region of Peru. Am J Trop Med Hyg 2007, 76:293-298.
• [44]Ewel KC: Swamps. In Ecosystems of Florida Edited by Myers RL, Ewel JJ. 1990, 281-323. [Orlando University of Central Florida Press]
• [45]Florida Department of Environmental Protection Bureau of Watershed Restoration: Northwest Florida Water Management District Land Use And Cover 2004. Tallahassee, FL: Florida Department of Environmental Protection; 2009.
• [46]Florida Department of Health: Weekly Data for Arbovirus Surveillance. 2010.
• [47]Ester M, Kriegel HP, Sander J, Xu X: A density-based algorithm for discovering clusters in large spatial databases with noise. Computer 1996, 6:226-231.
• [48]Otis DL, White GC: Autocorrelation of location estimates and the analysis of radiotracking data. J Wildl Manag 1999, 63:1039-1044.
• [49]Tufto J, Andersen R, Linnell J: Habitat use and ecological correlates of home range size in a small cervid: the roe deer. J Anim Ecol 1996, 65:715-724.
• [50]Arthur SM, Manly BFJ, McDonald LL, Garner GW: Assessing habitat selection when availability changes. Ecology 1996, 77:215-227.
• [51]Conner M, Plowman B, Leopold BD, Lovell C: Influence of time-in-residence on home range and habitat use of bobcats. J Wildl Manag 1999, 63:261-269.
• [52]Aebischer NJ, Robertson PA, Kenward RE: Compositional analysis of habitat use from animal radio-tracking data. Ecology 1993, 74:1313-1325.
• [53]Rochlin I, Turbow D, Gomez F, Ninivaggi DV, Campbell SR: Predictive mapping of human risk for West Nile virus (WNV) based on environmental and socioeconomic factors. PLoS One 2011, 6:e23280.
• [54]Yamar BA, Diallo D, Kebe CM, Dia I, Diallo M: Aspects of bioecology of two rift valley fever virus vectors in Senegal (West Africa): aedes vexans and culex poicilipes (Diptera: Culicidae). J Med Entomol 2005, 42:739-750.
• [55]Morris CD, Larson VL, Lounibos LP: Measuring mosquito dispersal for control programs. J Am Mosq Control Assoc 1991, 7:608-615.
• [56]Estep LK, Burkett-Cadena ND, Hill GE, Unnasch RS, Unnasch TR: Estimation of dispersal distances of Culex erraticus in a focus of eastern equine encephalitis virus in the southeastern United States. J Med Entomol 2010, 47:977-986.
• [57]Lohr M, Collins BM, Castelli PM, Williams CK: Life on the edge: northern bobwhite ecology at the northern periphery of their range. J Wildl Manag 2011, 75:52-60.
• [58]Dickson BG, Beier P: Home-range and habitat selection by adult cougars in Southern California. J Wildl Manag 2002, 66:1235-1245.
• [59]Conner LM, Smith MD, Burger LW: A comparison of distance-based and classification-based analyses of habitat use. Ecology 2003, 84:526-531.
• [60]Wendel HEW, Downs JA, Mihelcic JR: Assessing equitable access to urban green space: the role of engineered water infrastructure. Environ Sci Technol 2011, 45:6728-6734.