scholarly journals Modeling Potential Habitat for Amblyomma Tick Species in California

Insects ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 201 ◽  
Author(s):  
Emily L. Pascoe ◽  
Matteo Marcantonio ◽  
Cyril Caminade ◽  
Janet E. Foley

The Amblyomma genus of ticks comprises species that are aggressive human biters and vectors of pathogens. Numerous species in the genus are undergoing rapid range expansion. Amblyomma ticks have occasionally been introduced into California, but as yet, no established populations have been reported in the state. Because California has high ecological diversity and is a transport hub for potentially parasitized humans and animals, the risk of future Amblyomma establishment may be high. We used ecological niche modeling to predict areas in California suitable for four tick species that pose high risk to humans: Amblyomma americanum, Amblyomma maculatum, Amblyomma cajennense and Amblyomma mixtum. We collected presence data in the Americas for each species from the published literature and online databases. Twenty-three climatic and ecological variables were used in a MaxEnt algorithm to predict the distribution of each species. The minimum temperature of the coldest month was an important predictor for all four species due to high mortality of Amblyomma at low temperatures. Areas in California appear to be ecologically suitable for A. americanum, A. maculatum, and A. cajennense, but not A. mixtum. These findings could inform targeted surveillance prior to an invasion event, to allow mitigation actions to be quickly implemented.

2017 ◽  
Vol 43 (2) ◽  
pp. 268
Author(s):  
Fredy A. Rivera-Páez ◽  
Marcelo B. Labruna ◽  
Thiago F. Martins ◽  
Bruno Rodrigues-Sampieri ◽  
María I. Camargo-Mathias

Gynandromorphism is a condition in which an organism simultaneously exhibits male and female morphological characteristics. In Colombia, the taxon Amblyomma cajennense is represented by the species Amblyomma patinoi and Amblyomma mixtum. In September of 2014, in the Colombian Orinoco region, adult ticks were collected and determined from natural infections in bovines and equines. A gynandromorph was described from a natural infestation on a bovine, and morphologically classified as A. mixtum. This is the first literature report of a gynandromorph of A. mixtum, and the first description of a gynandromorph for a tick species in Colombia.


Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Evan Greenspan ◽  
Anthony J. Giordano

Abstract Knowledge about the current distribution of threatened and/or understudied species is a fundamental component of conservation biology. Mapping species distributions based on recent known occurrences is particularly important for those that are rare or declining. Too often, cryptic species go undetected throughout parts of their range, whereas others just receive less research attention. We used contemporary presence data for the Pallas’s cat (Otocolobus manul), a small cryptic felid, to characterize potential rangewide and regional habitat for the species and identify those abiotic and biotic variables most influencing its distribution. Several regions lacking contemporary occurrence records contain potential habitat for Pallas’s cats, including the Koh-i-Baba Mountains of Afghanistan, Qinghai-Tibetan Plateau, steppes of Inner Mongolia, Kunlun Mountains of China, and Tian Shan and Pamir Mountains of Kyrgyzstan, Tajikistan, and China. Some of these areas have not been included in prior rangewide distribution assessments. The distribution of pikas (Ochotona spp.), small mammals that likely represent a critical prey species everywhere they are sympatric, was the most important factor affecting the Pallas’s cat’s distribution. This suggests Pallas’s cats may be prey specialists, and that pika presence and habitat are critical considerations for future Pallas’s cat surveys and in the development of regional conservation actions.


Author(s):  
Ashley P G Dowling ◽  
Sean G Young ◽  
Kelly Loftin

Abstract Tick-borne diseases (TBD) in humans have dramatically increased over recent years and although the bulk of cases are attributable to Lyme Disease in the Northeastern US, TBDs like spotted fever rickettsiosis and ehrlichiosis heavily impact other parts of the country, namely the mid-south. Understanding tick and pathogen distributions and prevalence traditionally requires active surveillance, which quickly becomes logistically and financially unrealistic as the geographic area of focus increases. We report on a community science effort to survey ticks across Arkansas to obtain updated data on tick distributions and prevalence of human tick-borne disease-causing pathogens in the most commonly encountered ticks. During a 20-mo period, Arkansans submitted 9,002 ticks from 71 of the 75 counties in the state. Amblyomma americanum was the most common tick species received, accounting for 76% of total tick submissions. Nearly 6,000 samples were screened for spotted fever group Rickettsia (SFGR) and Ehrlichia, resulting in general prevalence rates of 37.4 and 5.1%, respectively. In addition, 145 ticks (2.5%) were infected with both SFGR and Ehrlichia. Arkansas Department of Health reported 2,281 spotted fever and 380 ehrlichiosis cases during the same period as our tick collections. Since known SFGR vectors Dermacentor variabilis and Amblyomma maculatum were not the most common ticks submitted, nor did they have the highest prevalence rates of SFGR, it appears that other tick species play the primary role in infecting humans with SFGR. Our investigation demonstrated the utility of community science to efficiently and economically survey ticks and identify vector-borne disease risk in Arkansas.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Stefania Zanet ◽  
Ezio Ferroglio ◽  
Elena Battisti ◽  
Paolo Tizzani

Tick-borne diseases and especially protozoa of the genus Babesia, are gaining increasing attention as emerging zoonotic pathogens. Zoonotic species like B. venatorum and B. microti have wild animals as main reservoir hosts. We propose a habitat suitability model for Babesia spp., as tool for institutions and policy makes to better understand the entity of Babesia presence, to improve diagnostic awareness and to optimize screening and preventive actions. The probability of presence of Babesia spp. was estimated using as presence data, wild ruminants positive by PCR to Babesia spp. which were correlated to environmental factors that can favor or limit vector and host availability. We developed three separate models to discriminate the different roles of Red deer and Roe deer and Alpine chamois in Babesia spp. epidemiology. A comprehensive model using all presence data from all ungulates species  was also developed. The overall suitable area for Babesia spp. in this simulation is of 3723 km2, which correspond to 15.51% of the background regional territory. The model developed was empirically validated assessing tick abundance in randomly chosen areas classified by the model as moderately or highly suitable for Babesia spp. Collected ticks were tested by PCR for Babesia spp. to confirm model predictions as infection prevalence with Babesia spp. was significantly higher in areas predicted as highly suitable compared to those classified by the model as moderately suitable for Babesia spp.  (X2=5.05 p<0.05, Odds Ratio OR= 2.12 CI95% 1.1-4.1).


Author(s):  
Surendra Raj Sharma ◽  
Shahid Karim

Ticks and tick-borne diseases are significant public health concerns. Bioactive molecules in tick saliva facilitate prolonged blood-feeding and transmission of tick-borne pathogens to the vertebrate host. Alpha-gal syndrome (AGS), a newly reported food allergy, is believed to be induced by saliva proteins decorated with a sugar molecule, the oligosaccharide galactose-⍺-1,3-galactose (α-gal). This syndrome is characterized by an IgE antibody-directed hypersensitivity against α-gal. The α-gal antigen was discovered in the salivary glands and saliva of various tick species including, the Lone Star tick (Amblyomma americanum). The underlying immune mechanisms linking tick bites with α-gal-specific IgE production are poorly understood and are crucial to identify and establish novel treatments for this disease. This article reviews the current understanding of AGS and its involvement with tick species.


Author(s):  
S. S. Thakuri ◽  
P. Shrestha ◽  
M. Deuba ◽  
P. Shah ◽  
O. P. Bhandari ◽  
...  

Abstract. Invasive Alien Plant Species are spreading outside of their natural geographic range. Water hyacinth (Eichhornia crassipes) is one of the most widely and rapidly spreading invasive species throughout the tropical and subtropical regions of Nepal. In the last decade, water hyacinth has become a chronic problem in many major lakes of Nepal which have affected the habitat aquatic plants and animals. Our study focuses on potential habitat modeling of Water hyacinth over the major lakes of Nepal using Maxent algorithm. Primary data used for modeling were 19 bioclimatic variables and Shuttle Radar Topography Model (SRTM) Digital Elevation Model (DEM). After preparation of the species distribution model, major lakes of Nepal were overlaid over the model to prepare potential invasive map. The performance and accuracy of potential habitat distribution model was evaluated using parameter Area under the Receiver Operating Characteristic Curve (AUC) which was within the range of 0.9–1. Validation of the model was done for the year 2015 with precision and recall, overall accuracy and F-measure and its values are 93% and 85%, 87% and 89% respectively. The model prepared for 2030 and 2050 shows the most suitable habitat for water hyacinth is in province 2 of Nepal and the moderately suitable habitat for this species is plain area of Province 4, 7 and 5. Similarly, the area of potential habitat has been increasing from current scenario to 2030 and 2050. From the potential invasion map, it can be observed that lakes in the Terai and Churey regions have the high risk of invasion of water hyacinth.


2010 ◽  
Vol 19 (3) ◽  
pp. 192-194 ◽  
Author(s):  
Marcelo Bahia Labruna ◽  
Fábio Silva Barbieri ◽  
Thiago Fernandes Martins ◽  
Luciana Gatto Brito ◽  
Francisco Dimas Sales Ribeiro

In the present study, we provide new tick records from Vilhena Municipality, in the Southeast of the State of Rondônia, Northern Brazil. Ticks collected from a capybara, Hydrochoerus hydrochaeris (Linnaeus), were identified as Amblyomma romitii Tonelli-Rondelli (1 female), and Amblyomma sp. (1 larva). Ticks collected from a harpy eagle, Harpia harpyja (Linnaeus), were identified as Amblyomma cajennense (Fabricius) (16 nymphs) and Haemaphysalis juxtakochi Cooley (1 nymph). Ticks collected from a yellow-footed tortoise, Chelonoidis denticulada (Linnaeus), were identified as Amblyomma rotundatum Koch (10 females, 2 nymphs), and Amblyomma sp. (2 larvae). The present record of A. romitii is the first in the State of Rondônia, and represents the southernmost record for this tick species, indicating that its distribution area is much larger than currently recognized. Although both A. cajennense and H. juxtakochi have been reported parasitizing various bird species, we provide the first tick records on a harpy eagle. A. rotundatum is widespread in the State of Rondônia, and has been previously reported on the yellow-footed tortoise. The present records increase the tick fauna of Rondônia to 26 species.


Sign in / Sign up

Export Citation Format

Share Document