For all researches, please visit our "Peer-reviewed publications" page.
Samy A, Elaagip A, Kenawy M, Ayres C, Peterson A, Soliman D et al. (2016)
Climate Change Influences on the Global Potential Distribution of the Mosquito Culex quinquefasciatus, Vector of West Nile Virus and Lymphatic Filariasis
PLOS ONE 11(10) e0163863.
Rapid emergence of most vector-borne diseases (VBDs) may be associated with range expansion of vector populations. Culex quinquefasciatus Say 1823 is a potential vector of West Nile virus, Saint Louis encephalitis virus, and lymphatic filariasis. We estimated the potential distribution of Cx. quinquefasciatus under both current and future climate conditions. The present potential distribution of Cx. quinquefasciatus showed high suitability across low-latitude parts of the world, reflecting the current distribution of the species. Suitable conditions were identified also in narrow zones of North Africa and Western Europe. Model transfers to future conditions showed a potential distribution similar to that under present-day conditions, although with higher suitability in southern Australia. Highest stability with changing climate was between 30°S and 30°N. The areas present high agreement among diverse climate models as regards distributional potential in the future, but differed in anticipating potential for distribution in North and Central Africa, southern Asia, central USA, and southeastern Europe. Highest disparity in model predictions across representative concentration pathways (RCPs) was in Saudi Arabia and Europe. The model predictions allow anticipation of changing distributional potential of the species in coming decades.
Samy A, Peterson A (2016)
PloS one 11(3) e0150489.
The geographic distribution of arboviruses has received considerable attention after several dramatic emergence events around the world. Bluetongue virus (BTV) is classified among category "A" diseases notifiable to the World Organization of Animal Health (OIE), and is transmitted among ruminants by biting midges of the genus Culicoides. Here, we developed a comprehensive occurrence data set to map the current distribution, estimate the ecological niche, and explore the future potential distribution of BTV globally using ecological niche modeling and based on diverse future climate scenarios from general circulation models (GCMs) for four representative concentration pathways (RCPs). The broad ecological niche and potential geographic distribution of BTV under present-day conditions reflected the disease's current distribution across the world in tropical, subtropical, and temperate regions. All model predictions were significantly better than random expectations. As a further evaluation of model robustness, we compared our model predictions to 331 independent records from most recent outbreaks from the Food and Agriculture Organization Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases Information System (EMPRES-i); all were successfully anticipated by the BTV model. Finally, we tested ecological niche similarity among possible vectors and BTV, and could not reject hypotheses of niche similarity. Under future-climate conditions, the potential distribution of BTV was predicted to broaden, especially in central Africa, United States, and western Russia.
Samy A, van de Sande W, Fahal A, Peterson A (2014)
Mapping the potential risk of mycetoma infection in Sudan and South Sudan using ecological niche modeling
PLoS neglected tropical diseases 8(10) e3250.
In 2013, the World Health Organization (WHO) recognized mycetoma as one of the neglected tropical conditions due to the efforts of the mycetoma consortium. This same consortium formulated knowledge gaps that require further research. One of these gaps was that very few data are available on the epidemiology and transmission cycle of the causative agents. Previous work suggested a soil-borne or Acacia thorn-prick-mediated origin of mycetoma infections, but no studies have investigated effects of soil type and Acacia geographic distribution on mycetoma case distributions. Here, we map risk of mycetoma infection across Sudan and South Sudan using ecological niche modeling (ENM). For this study, records of mycetoma cases were obtained from the scientific literature and GIDEON; Acacia records were obtained from the Global Biodiversity Information Facility. We developed ENMs based on digital GIS data layers summarizing soil characteristics, land-surface temperature, and greenness indices to provide a rich picture of environmental variation across Sudan and South Sudan. ENMs were calibrated in known endemic districts and transferred countrywide; model results suggested that risk is greatest in an east-west belt across central Sudan. Visualizing ENMs in environmental dimensions, mycetoma occurs under diverse environmental conditions. We compared niches of mycetoma and Acacia trees, and could not reject the null hypothesis of niche similarity. This study revealed contributions of different environmental factors to mycetoma infection risk, identified suitable environments and regions for transmission, signaled a potential mycetoma-Acacia association, and provided steps towards a robust risk map for the disease.
Castilla A, Valdeón A, Cogalniceaunu D, Gosá A, Saifelnasr E, Naimi S et al. (2013)
First record of a gecko species to the fauna of Qatar: Hemidactylus persicus Anderson, 1872 (Gekkonidae)
Q Science Connect 1872.
We report the discovery of a gecko species, the Persian leaf-toed gecko Hemidactylus persicus Anderson, 1872 (Gekkonidae) in Qatar, found on Halul Island. According to the Qatar National Biodiversity Surveys and the available international literature H. persicus was not previously recorded in Qatar. Its known range covers the north east of the Arabian Peninsula, Bahrain, the United Arab Emirates, and south western Asia. Our findings bridge the current geographic gap in the known distribution of the species from Saudi Arabia to Asia. We believe that the species could also be present in the Qatar peninsula. A thorough field survey is needed in order to map the range of this species in the State of Qatar.
Valdeón A, Castilla A, Cogalniceaunu D, Gosá A, Alkuwary A, Saifelnasr E et al. (2013)
On the presence and distribution of the Gulf sand gecko, Pseudoceramodactylus khobarensis Haas, 1957 (Reptilia: Squamata: Gekkonidae) in Qatar
Q Science Connect 1957.
The Gulf sand gecko (Pseudoceramodactylus khobarensis Haas, 1957) is a nocturnal gecko endemic to the Arabian Gulf countries. In this study we report the presence of this species in Qatar for the first time. Our findings bridge one of the current geographic gaps in the known distribution range of this species. In Qatar, the species has been found on the mainland and on two islands occupying coastal salty habitats with shrubs. The islands are the smallest where this species is known to occur. We believe that this gecko species is more widely distributed in Qatar than we report here and that an extensive inventory is required to map the full range of the species in Qatar and also in other countries of the Arabian Gulf.
Keywords: Arabian Gulf, Atlas, Biodiversity, Range, Reptile, Stenodactylus khobarensis