Emergence of the invasive Asian bush mosquito, Aedes (Finlaya) japonicus japonicus, in an urban area, Romania.
Ontology highlight
ABSTRACT: Background
A study conducted at the International Airport of Cluj-Napoca, Romania, with the aim of investigating the presence/absence of invasive Aedes mosquito species resulted in finding Aedes japonicus japonicus (Theobald 1901) eggs in one of the ovitraps placed on site.Methods
The study was carried out between 30 June and 29 September 2020. On 24 August, 26 eggs were collected and later hatched at the University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca's insectary. On 15 October another adult female Ae. japonicus was caught entering a building in the center of the city, about 7 km from the first sampling spot.Results
The mosquitoes were identified morphologically and confirmed by molecular analysis, based on the genetic analysis of the mitochondrial gene cytochrome c oxidase subunit 1 (COI).Conclusion
This is the first report of the species in Romania, highlighting the need for surveillance and implemented control methods. However, in Romania to our knowledge only Aedes albopictus has been established; further studies are required to learn about this new invasive species' status in Romania.
SUBMITTER: Horvath C
PROVIDER: S-EPMC8024677 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:BackgroundAedes japonicus is a mosquito species native to North-East Asia that was first found established outside its original geographic distribution range in 1998 and has since spread massively through North America and Europe. In the Czech Republic, the species was not reported before 2021.MethodsAedes invasive mosquitoes (AIM) are routinely surveyed in the Czech Republic by ovitrapping at potential entry ports. This surveillance is supported by appeals to the population to report uncommon mosquitoes. The submission of an Ae. japonicus specimen by a citizen in 2021 was followed by local search for aquatic mosquito stages in the submitter's garden and short-term adult monitoring with encephalitis virus surveillance (EVS) traps in its surroundings. Collected Ae. japonicus specimens were subjected to nad4 haplotype and microsatellite analyses.ResultsAedes japonicus was detected for the first time in the Czech Republic in 2021. Aquatic stages and adults were collected in Prachatice, close to the Czech-German border, and eggs in Mikulov, on the Czech-Austrian border. Morphological identification was confirmed by molecular taxonomy. Genetic analysis of specimens and comparison of genetic data with those of other European populations, particularly from Germany, showed the Prachatice specimens to be most closely related to a German population. The Mikulov specimens were more distantly related to those, with no close relatives identifiable.ConclusionsAedes japonicus is already widely distributed in Germany and Austria, two countries neighbouring the Czech Republic, and continues to spread rapidly in Central Europe. It must therefore be assumed that the species is already present at more than the two described localities in the Czech Republic and will further spread in this country. These findings highlight the need for more comprehensive AIM surveillance in the Czech Republic.
| S-EPMC9277878 | biostudies-literature
Project description:The Asian bush mosquito Aedes japonicus is rapidly invading North America and Europe. Due to its potential to transmit multiple pathogenic arthropod-borne (arbo)viruses including Zika virus, West Nile virus, and chikungunya virus, it is important to understand the biology of this vector mosquito in more detail. In addition to arboviruses, mosquitoes can also carry insect-specific viruses that are receiving increasing attention due to their potential effects on host physiology and arbovirus transmission. In this study, we characterized the collection of viruses, referred to as the virome, circulating in Ae. japonicus populations in the Netherlands and France. Applying a small RNA-based metagenomic approach to Ae. japonicus, we uncovered a distinct group of viruses present in samples from both the Netherlands and France. These included one known virus, Ae. japonicus narnavirus 1 (AejapNV1), and three new virus species that we named Ae. japonicus totivirus 1 (AejapTV1), Ae. japonicus anphevirus 1 (AejapAV1) and Ae. japonicus bunyavirus 1 (AejapBV1). We also discovered sequences that were presumably derived from two additional novel viruses: Ae. japonicus bunyavirus 2 (AejapBV2) and Ae. japonicus rhabdovirus 1 (AejapRV1). All six viruses induced strong RNA interference responses, including the production of twenty-one nucleotide-sized small interfering RNAs, a signature of active replication in the host. Notably, AejapBV1 and AejapBV2 belong to different viral families; however, no RNA-dependent RNA polymerase sequence has been found for AejapBV2. Intriguingly, our small RNA-based approach identified an ∼1-kb long ambigrammatic RNA that is associated with AejapNV1 as a secondary segment but showed no similarity to any sequence in public databases. We confirmed the presence of AejapNV1 primary and secondary segments, AejapTV1, AejapAV1, and AejapBV1 by reverse transcriptase polymerase chain reaction (PCR) in wild-caught Ae. japonicus mosquitoes. AejapNV1 and AejapTV1 were found at high prevalence (87-100 per cent) in adult females, adult males, and larvae. Using a small RNA-based, sequence-independent metagenomic strategy, we uncovered a conserved and prevalent virome among Ae. japonicus mosquito populations. The high prevalence of AejapNV1 and AejapTV1 across all tested mosquito life stages suggests that these viruses are intimately associated with Ae. japonicus.
| S-EPMC10460169 | biostudies-literature
Project description:BACKGROUND:The Asian bush mosquito Aedes japonicus is invading Europe and was first discovered in Lelystad, the Netherlands in 2013, where it has established a permanent population. In this study, we investigated the vector competence of Ae. japonicus from the Netherlands for the emerging Zika virus (ZIKV) and zoonotic Usutu virus (USUV). ZIKV causes severe congenital microcephaly and Guillain-Barré syndrome in humans. USUV is closely related to West Nile virus, has recently spread throughout Europe and is causing mass mortality of birds. USUV infection in humans can result in clinical manifestations ranging from mild disease to severe neurological impairments. METHODOLOGY/PRINCIPAL FINDINGS:In our study, field-collected Ae. japonicus females received an infectious blood meal with ZIKV or USUV by droplet feeding. After 14 days at 28°C, 3% of the ZIKV-blood fed mosquitoes and 13% of the USUV-blood fed mosquitoes showed virus-positive saliva, indicating that Ae. japonicus can transmit both viruses. To investigate the effect of the mosquito midgut barrier on virus transmission, female mosquitoes were intrathoracically injected with ZIKV or USUV. Of the injected mosquitoes, 96% (ZIKV) and 88% (USUV) showed virus-positive saliva after 14 days at 28°C. This indicates that ZIKV and USUV can efficiently replicate in Ae. japonicus but that a strong midgut barrier is normally restricting virus dissemination. Small RNA deep sequencing of orally infected mosquitoes confirmed active replication of ZIKV and USUV, as demonstrated by potent small interfering RNA responses against both viruses. Additionally, de novo small RNA assembly revealed the presence of a novel narnavirus in Ae. japonicus. CONCLUSIONS/SIGNIFICANCE:Given that Ae. japonicus can experimentally transmit arthropod-borne viruses (arboviruses) like ZIKV and USUV and is currently expanding its territories, we should consider this mosquito as a potential vector for arboviral diseases in Europe.
| S-EPMC7153878 | biostudies-literature
Project description:BackgroundIn 2011 we identified the Asian bush mosquito, Aedes japonicus japonicus (Theobald, 1901) (Diptera: Culicidae) for the first time in northern Slovenia and in the bordering Austrian federal state of Styria. Between May and July 2012 the distribution area of Ae. j. japonicus was already found to be extended westwards into Carinthia and eastwards towards Burgenland and bordering Hungary. In August 2012 the species was first detected in a western province of Hungary. In subsequent years, follow-up field studies demonstrated an active spread westwards throughout Carinthia, reaching the border to northern Italy.FindingsIn July 2015 several aquatic-stage specimens of the species were discovered at three different sites in the Friuli Venezia Giulia region, north-eastern Italy. In September 2015, co-occurrence of Ae. j. japonicus and Aedes albopictus (Skuse, 1895) was observed in the same sample in that region.ConclusionsAe. j. japonicus actively extended its geographic range from an established population in Carinthia (Austria) southwards to northern Italy by crossing Alpine ranges. Since Ae. albopictus and Aedes koreicus (Edwards, 1917) are already well established in northern Italy, it will be pivotal to monitor the consequences of a third invasive mosquito species trying to populate the same geographic region.
| S-EPMC4869290 | biostudies-literature
Project description:The invasive Asian bush mosquito Aedes japonicus japonicus was first recognised as established in Germany in 2008. In addition to the first known and quickly expanding population in the southwestern part of the country, three separate populations were discovered in West, North and southeastern Germany in 2012, 2013 and 2015, respectively, by means of the 'Mueckenatlas', a German instrument of passive mosquito surveillance. Since the first findings of mosquito specimens in West and North Germany, these regions were checked annually for continuing colonisation and spread of the species. Both affected areas were covered by a virtual 10x10km2 grid pattern in the cells of which cemeteries were screened for immature stages of the mosquito. The cells were considered populated as soon as larvae or pupae were detected, whereas they were classified as negative when no mosquito stages were found in the cemeteries of at least three different towns or villages. Presence was also recorded when Ae. j. japonicus adults were submitted to the 'Mueckenatlas' from the respective cell or when there was evidence of local occurrence in localities other than cemeteries. Based on this approach, a significant expansion of the populated area was documented in West Germany since the first detection of Ae. j. japonicus in 2012 (increase in positive grid cells by more than 400%), while the North German population appears not to be expanding so far (reduction of positive grid cells by ca. 30% since 2013). As Ae. j. japonicus finds suitable climatic and ecological conditions in Germany, the differential expansion of the two populations might be attributed to the West German population being older and thus more firmly established than the closely related but younger North German population that might still be in its founder phase. However, geographic spread of all German populations in the future is anticipated. Continuous surveillance is recommended, as Ae. j. japonicus is a competent vector of several pathogens in the laboratory.
| S-EPMC5148077 | biostudies-literature
Project description:BackgroundAedes japonicus japonicus has expanded beyond its native range and has established in multiple European countries, including Belgium. In addition to the population located at Natoye, Belgium, locally established since 2002, specimens were recently collected along the Belgian border. The first objective of this study was therefore to investigate the origin of these new introductions, which were assumed to be related to the expansion of the nearby population in western Germany. Also, an intensive elimination campaign was undertaken at Natoye between 2012 and 2015, after which the species was declared to be eradicated. This species was re-detected in 2017, and thus the second objective was to investigate if these specimens resulted from a new introduction event and/or from a few undetected specimens that escaped the elimination campaign.MethodsPopulation genetic variation at nad4 and seven microsatellite loci was surveyed in 224 and 68 specimens collected in Belgium and Germany, respectively. German samples were included as reference to investigate putative introduction source(s). At Natoye, 52 and 135 specimens were collected before and after the elimination campaign, respectively, to investigate temporal changes in the genetic composition and diversity.ResultsAt Natoye, the genotypic microsatellite make-up showed a clear difference before and after the elimination campaign. Also, the population after 2017 displayed an increased allelic richness and number of private alleles, indicative of new introduction(s). However, the Natoye population present before the elimination programme is believed to have survived at low density. At the Belgian border, clustering results suggest a relation with the western German population. Whether the introduction(s) occur via passive human-mediated ground transport or, alternatively, by natural spread cannot be determined yet from the dataset.ConclusionFurther introductions within Belgium are expected to occur in the near future, especially along the eastern Belgian border, which is at the front of the invasion of Ae. japonicus towards the west. Our results also point to the complexity of controlling invasive species, since 4 years of intense control measures were found to be not completely successful at eliminating this exotic at Natoye.
| S-EPMC7995749 | biostudies-literature
Project description:BackgroundThe invasive mosquito species, Aedes japonicus japonicus, was detected in northeastern Italy for the first time in 2015, at the border with Austria. After this finding, a more intensive monitoring was carried out to assess its distribution and to collect biological data. Herein, we report the results of four years (2015-2018) of activity.MethodsThe presence of Ae. j. japonicus was checked in all possible breeding sites through collections of larvae. The monitoring started from the site of the first detection at the Austrian border and then was extended in all directions. The mosquitoes were identified morphologically and molecularly.ResultsAedes j. japonicus was found in 58 out of 73 municipalities monitored (79.5%). In total (2015-2018), 238 sampling sites were monitored and 90 were positive for presence of Ae. j. japonicus larvae (37.8%). The mosquito was collected mainly in artificial containers located in small villages and in rural areas. Cohabitation with other mosquito species was observed in 55.6% of the samplings.ConclusionsAedes j. japonicus is well established in Italy and in only four years has colonised two Italian Regions, displaying rapid spreading throughout hilly and mountainous areas. Colonization towards the south seems limited by climatic conditions and the occurrence of a large population of the larval competitor, Ae. albopictus. The further spread of Ae. j. japonicus has the potential to pose new threats of zoonotic agents (i.e. Dirofilaria spp. and West Nile virus) within areas at altitudes previously considered at negligible risk in Italy.
| S-EPMC6434805 | biostudies-literature
Project description:BackgroundRecently, two invasive Aedes mosquito species, Ae. japonicus and Ae. koreicus, are circulating in several European countries posing potential health risks to humans and animals. Vector control is the main option to prevent mosquito-borne diseases, and an accurate genome sequence of these mosquitoes is essential to better understand their biology and to develop effective control strategies.MethodsA de novo genome assembly of Ae. japonicus (Ajap1) and Ae. koreicus (Akor1) has been produced based on a hybrid approach that combines Oxford Nanopore long-read and Illumina short-read data. Their quality was ascertained using various metrics. Masking of repetitive elements, gene prediction and functional annotation was performed.ResultsSequence analysis revealed a very high presence of repetitive DNA and, among others, thermal adaptation genes and insecticide-resistance genes. Through the RNA-seq analysis of larvae and adults of Ae. koreicus and Ae. japonicus exposed to different temperatures, we also identified genes showing a differential temperature-dependent activation.ConclusionsThe assembly of Akor1 and Ajap1 genomes constitutes the first updated collective knowledge of the genomes of both mosquito species, providing the possibility of understanding key mechanisms of their biology such as the ability to adapt to harsh climates and to develop insecticide-resistance mechanisms.
| S-EPMC10658958 | biostudies-literature
Project description:BackgroundThe Korean bush mosquito Aedes koreicus was recently reported to have established a population in western Germany (Wiesbaden) in 2016. The species is difficult to distinguish morphologically from its close relative, the invasive Japanese bush mosquito Ae. japonicus, which is already widely distributed in many parts of Germany, including the area colonised by Ae. koreicus. Genetic confirmation of morphologically identified "Ae. japonicus" collection material, however, had only been done exceptionally before the German Ae. koreicus population became known.MethodsDried archived "Ae. japonicus" specimens both from the municipality of Wiesbaden and from deliberately and randomly selected distribution sites all over Germany were re-examined morphologically and genetically for admixture by Ae. koreicus. Moreover, cemeteries in the greater Wiesbaden area were sampled in 2019 and 2020 to check for Ae. koreicus spread. Korean and Japanese bush mosquitoes submitted to the German citizen science mosquito monitoring scheme "Mueckenatlas" in 2019 and 2020 were also subjected to particularly thorough species identification. The ND4 DNA sequences generated in this study in the context of species identification were phylogenetically compared to respective GenBank entries of Ae. koreicus. As a by-product, several genetic markers were evaluated for their suitability to identify Ae. koreicus.ResultsAedes koreicus specimens could be identified in mosquito collection material and submissions from Wiesbaden from 2015 onwards, suggesting establishment to have happened in the same year as Ae. japonicus establishment. Detections of Ae. koreicus from 2019 and 2020 in Wiesbaden indicate a negligible enlargement of the populated area as described for 2018. Two Ae. koreicus specimens were also submitted from the city of Munich, southern Germany, in 2019 but further specimens could not be identified during immediate local inspections. Comparison of ND4 sequences generated in this and other studies demonstrate a high degree of homology, suggesting that this DNA region is not informative enough for clarification of origins and relationships of Ae. koreicus populations. For genetic identification of Ae. koreicus, PCR primers used for classical CO1 barcoding were found to lead to mismatches and produce no or incorrect amplicons. Alternative CO1 primers or a validated ND4 marker should be used instead.ConclusionsAedes koreicus is probably introduced into Germany every now and then but rarely succeeds in becoming established. As with most European populations, the German population is characterised by a limited expansion tendency. Since Ae. koreicus is a potential vector, however, Asian bush mosquitoes found at new places should be examined quite carefully and known distribution areas of Ae. japonicus regularly checked for the presence of Ae. koreicus.
| S-EPMC8588644 | biostudies-literature
Project description:The Asian tiger mosquito Aedes albopictus is currently one of the most threatening invasive species in the world. Native to Southeast Asia, the species has spread throughout the world in the past 30 years and is now present in every continent but Antarctica. Because it was the main vector of recent Dengue and Chikungunya outbreaks, and because of its competency for numerous other viruses and pathogens such as the Zika virus, A. albopictus stands out as a model species for invasive diseases vector studies. A synthesis of the current knowledge about the genetic diversity of A. albopictus is needed, knowing the interplays between the vector, the pathogens, the environment and their epidemiological consequences. Such resources are also valuable for assessing the role of genetic diversity in the invasive success. We review here the large but sometimes dispersed literature about the population genetics of A. albopictus. We first debate about the experimental design of these studies and present an up-to-date assessment of the available molecular markers. We then summarize the main genetic characteristics of natural populations and synthesize the available data regarding the worldwide structuring of the vector. Finally, we pinpoint the gaps that remain to be addressed and suggest possible research directions.
| S-EPMC4981682 | biostudies-literature