Attila János Trájer

Impacts of urbanisation level and distance from potential natural mosquito breeding habitats on the abundance of canine dirofilariosis

Dirofilariosis is an emerging mosquito-borne veterinary and medical problem in the Northern hemisphere. The ecological investigation of 56 canine dirofilariosis cases in new endemic locations was performed in Szeged, Hungary. The aim was to analyse the influence of the spatial patterns of dog abundance and the potential mosquito breeding habitats on the spatial occurrence patterns of dirofilariosis in the city of Szeged. The limnoecological characterisation was based on the fluvial habitat classification of Amoros of natural water bodies; the built environment was evaluated using the UrbanisationScore urbanisation intensity measuring software. Dirofilaria immitis accounted for 51% and D. repens for 34.3% of the dirofilariosis cases, and in 20% of the cases only the Knotts test was positive. It was concluded that most of the cases were related to locations with a medium to high urbanisation index, although the proximity of mosquito-bearing waters also played an important role in the observed spatial infection patterns. We found that the distance from potential mosquito habitats and the urbanisation intensity determine the abundance of dirofilariosis in urban environments.

An ArcGIS Tool for Modeling the Climate Envelope with Feed-Forward ANN

This article is about the development and application of an ESRI ArcGIS tool that implements a multilayer, feed-forward artificial neural network (ANN) to study the climate envelopes of species. The supervised learning is achieved by a backpropagation algorithm. Based on the distribution and the grids of the climate (and edaphic data) of the reference and future periods, the tool predicts the future potential distribution of the studied species. The trained network can be saved and loaded. A modeling result based on the distribution of European larch (Larix decidua Mill.) is presented as a case study.

Expected changes in the length of Anopheles maculipennis (Diptera: Culicidae) larva season and the possibility of the re-emergence of malaria in Central and Eastern Europe and the North Balkan region

Anopheles maculipennis is one of the potential vectors of Plasmodium vivax caused malaria in Europe. Although potential malaria vectors are present in the continent, malaria was eradicated in historical times and recently absent in Central and East Europe and the North Balkan. Climate change may trigger the re-emergence of malaria in Europe positively affecting the seasonal patterns of the potential Anopheline vectors. The increasing length of the larva season of mosquito vectors is one of the risk factors of the re-emerging of malaria. The monthly relative abundance values of the larvae of Anopheles maculipennis were modeled for the reference period 1961–1990 and the periods 2011–2040 and 2041–2070 based on the REMO climate model for Central and East Europe and the North Balkan region. Strong, significant correlation (r2=0.94, p<0.0001) was found between the monthly relative abundances of larvae and monthly mean air temperature values in Hungary between March and November. The threshold of the larval activity of Anopheles maculipennis was found to be about 4 °C. Comparing the modeled relative abundances for 1961–1990, 2011–2040, and 2041–2070, April and October months showed the most notable changes. The model predicts that in Southeast Hungary, East Croatia, North Serbia, South Romania, and North Bulgaria, the main season will increase by +1 to +2 months to the period of 2041–2070 comparing to the reference period. The model also indicates that the complete main Anopheles maculipennis larva season of the mosquito will increase by two months in Southeast Hungary and at least 1 month in the other parts of the south Pannonian Ecoregion, in the North Balkan region including South Romania and North Bulgaria for 2041–2070. Key-words: ecological modeling, mean monthly temperature, Carpathian Basin, malaria mosquitoes