MOSQUITO RESISTANCE TO INSECTICIDES IN BULGARIA

Mosquitoes are a group of blood-sucking insects that plays a major role in disease transmission in both humans and animals. They can pose a heavy nuisance, or serve as vectors of numerous viruses and parasites on most continents, including Europe. The strategy for successful control of the mosquito populations relies on the use of insecticides of five different categories: organochlorines, organophosphates, carbamates, pyrethroids, and biopesticides. The extensive use of the first four classes has resulted in the development of resistance originating in various mechanisms. The main ones are metabolic resistance and genetic resistance, manifested by point mutations in the insecticide targets, resulting in limited binding of neurotoxic substances. Much data is available on mosquito insecticide resistance in Bulgaria between 1948 and 1990, but only regarding organochlorines, organophosphates and carbamates. There is no data on pyrethroid resistance, which should raise an alarm for both public health authorities and private pest control companies since the only insecticides registered for professional mosquito control nowadays are pyrethroids. Therefore, there is an urgent need for the use of modern multidisciplinary approaches to study the resistance of native and invasive species of mosquitoes to insecticides, which should be a key contribution to elucidating their role in the circulation of pathogens of humans and animals and optimizing methods for controlling their populations

Phylogeographic Aspects of Bat Lyssaviruses in Europe: A Review

During the last few decades, bat lyssaviruses have become the topic of intensive molecular and epidemiological investigations. Since ancient times, rhabdoviruses have caused fatal encephalitis in humans which has led to research into effective strategies for their eradication. Modelling of potential future cross-species virus transmissions forms a substantial component of the recent infection biology of rabies. In this article, we summarise the available data on the phylogeography of both bats and lyssaviruses in Europe and the adjacent reg ions, especially in the contact zone between the Palearctic and Ethiopian realms. Within these zones, three bat families are present with high potential for cross-species transmission and the spread of lyssaviruses in Phylogroup II to Europe (part of the western Palearctic). The lack of effective therapies for rabies viruses in Phylogroup II and the most divergent lyssaviruses generates impetus for additional phylogenetic and virological research within this geographical region

A mark-release-recapture study to estimate field performance of imported radio-sterilized male aedes albopictus in Albania

The pathogen transmitting Aedes albopictus mosquito is spreading rapidly in Europe, putting millions of humans and animals at risk. This species is well-established in Albania since its first detection in 1979. The sterile insect technique (SIT) is increasingly gaining momentum worldwide as a component of area-wide-integrated pest management. However, estimating how the sterile males will perform in the field and the size of target populations is crucial for better decision-making, designing and elaborating appropriate SIT pilot trials, and subsequent large-scale release strategies. A mark-release-recapture (MRR) experiment was carried out in Albania within a highly urbanized area in the city of Tirana. The radio-sterilized adults of Ae. albopictus Albania strain males were transported by plane from Centro Agricoltura Ambiente (CAA) mass-production facility (Bologna, Italy), where they were reared. In Albania, sterile males were sugar-fed, marked with fluorescent powder, and released. The aim of this study was to estimate, under field conditions, their dispersal capacity, probability of daily survival and competitiveness, and the size of the target population. In addition, two adult mosquito collection methods were also evaluated: BG-Sentinel traps baited with BG-Lure and CO2, (BGS) versus human landing catch (HLC). The overall recapture rates did not differ significantly between the two methods (2.36% and 1.57% of the total male released were recaptured respectively by BGS and HLC), suggesting a similar trapping efficiency under these conditions. Sterile males traveled a mean distance of 93.85 +/- 42.58 m and dispersed up to 258 m. Moreover, they were observed living in the field up to 15 days after release with an average life expectancy of 4.26 +/- 0.80 days. Whether mosquitoes were marked with green, blue, yellow, or pink, released at 3.00 p.m. or 6.00 p.m., there was no significant difference in the recapture, dispersal, and survival rates in the field. The Fried competitiveness index was estimated at 0.28. This mark-release-recapture study provided important data for better decision-making and planning before moving to pilot SIT trials in Albania. Moreover, it also showed that both BG-traps and HLC were successful in monitoring adult mosquitoes and provided similar estimations of the main entomological parameters needed