%0 Journal Article
%T Species Distribution Models and Ecological Suitability Analysis for Potential Tick Vectors of Lyme Disease in Mexico
%A Patricia Illoldi-Rangel
%A Chissa-Louise Rivaldi
%A Blake Sissel
%A Rebecca Trout Fryxell
%A Guadalupe Gordillo-P¨¦rez
%A Angel Rodr¨ªguez-Moreno
%A Phillip Williamson
%A Griselda Montiel-Parra
%A V¨ªctor S¨¢nchez-Cordero
%A Sahotra Sarkar
%J Journal of Tropical Medicine
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/959101
%X Species distribution models were constructed for ten Ixodes species and Amblyomma cajennense for a region including Mexico and Texas. The model was based on a maximum entropy algorithm that used environmental layers to predict the relative probability of presence for each taxon. For Mexico, species geographic ranges were predicted by restricting the models to cells which have a higher probability than the lowest probability of the cells in which a presence record was located. There was spatial nonconcordance between the distributions of Amblyomma cajennense and the Ixodes group with the former restricted to lowlands and mainly the eastern coast of Mexico and the latter to montane regions with lower temperature. The risk of Lyme disease is, therefore, mainly present in the highlands where some Ixodes species are known vectors; if Amblyomma cajennense turns out to be a competent vector, the area of risk also extends to the lowlands and the east coast. 1. Introduction Lyme disease, the most frequently reported tick-borne infectious disease in the United States and Europe [1, 2], is increasingly being reported from Mexico [3, 4], where disease cases are more prevalent during warm-weather months when ticks are active. The etiologic agent, Borrelia burgdorferi, enters the skin at the site of the tick bite; after incubating for 3¨C30 days, the bacteria migrate through the skin and may spread to lymph nodes or disseminate through the bloodstream to other parts of the body. While B. burgdorferi infection might be endemic in Mexico [3, 4] it is relatively rare in the southern USA making the question of its biogeography a matter of interest. Additionally, in Mexico, the epidemiology and biogeography of Lyme disease are not well understood [5]. Several tick species have recently been identified as containing B. burgdorferi using a DNA polymerase chain reaction and, therefore, may be considered as candidates that may be involved in the enzootic transmission cycle in both Mexico and South America. These include tick species from the genus Ixodes [3, 4] as well as Amblyomma cajennense [5, David Beck, personal communication]. While detection of B. burgdorferi DNA by polymerase chain reaction is not indicative of vector competence, the presence of B. burgdorferi in the molecular surveys does indicate a benefit from modeling the distribution of A. cajennense since it has been shown to feed on reservoirs for B. burgdorferi in Mexico. Additionally, the South American A. cajennense has been shown to be a competent vector for Rickettsia rickettsii [6], the causative agent of
%U http://www.hindawi.com/journals/jtm/2012/959101/