First interception of Aedes (Stegomyia) albopictus in Lucky bamboo shipments in Belgium

Six gel-and five water-transported Dracaena braunii shipments originating from the South coast of China were screened for exotic mosquito species during a surveillance project on exotic vectors in Belgium. In November 2013, a live Aedes (Stegomyia) albopictus larva was detected in a gel substrate. This is the first direct evidence of the importation of Ae. albopictus on gel-transported Lucky bamboo. It also confirms that the importation risk of Ae. albopictus by transport of ornamental bamboo plants remains. In addition to the registration of appropriate biocides, a structured and permanent surveillance programme is needed in Belgium to allow for the early detection of invasive mosquito species and the timely implementation of control measures. JournalThe Federal Agency for the Safety of the Food Chain (FASFC)http://e-m-b.orgam201

Esperanza Window Traps for the collection of anthropophilic blackflies (Diptera: Simuliidae) in Uganda and Tanzania.

There is an increasing need to evaluate the impact of chemotherapeutic and vector-based interventions as onchocerciasis affected countries work towards eliminating the disease. The Esperanza Window Trap (EWT) provides a possible alternative to human landing collections (HLCs) for the collection of anthropophilic blackflies, yet it is not known whether current designs will prove effective for onchocerciasis vectors throughout sub-Saharan Africa. EWTs were deployed for 41 days in northern Uganda and south eastern Tanzania where different Simulium damnosum sibling species are responsible for disease transmission. The relative efficacy of EWTs and HLCs was compared, and responses of host-seeking blackflies to odour baits, colours, and yeast-produced CO2 were investigated. Blue EWTs baited with CO2 and worn socks collected 42.3% (2,393) of the total S. damnosum s.l. catch in northern Uganda. Numbers were comparable with those collected by HLCs (32.1%, 1,817), and higher than those collected on traps baited with CO2 and BG-Lure (25.6%, 1,446), a synthetic human attractant. Traps performed less well for the collection of S. damnosum s.l. in Tanzania where HLCs (72.5%, 2,432) consistently outperformed both blue (16.8%, 563) and black (10.7%, 360) traps baited with CO2 and worn socks. HLCs (72.3%, 361) also outperformed sock-baited (6.4%, 32) and BG-Lure-baited (21.2%, 106) traps for the collection of anthropophilic Simulium bovis in northern Uganda. Contrasting blackfly distributions were observed on traps in Uganda and Tanzania, indicating differences in behaviour in each area. The success of EWT collections of S. damnosum s.l. in northern Uganda was not replicated in Tanzania, or for the collection of anthropophilic S. bovis. Further research to improve the understanding of behavioural responses of vector sibling species to traps and their attractants should be encouraged

The blackfly vectors and transmission of Onchocerca volvulus in Mahenge, south eastern Tanzania.

The Mahenge Mountains onchocerciasis focus in south eastern Tanzania was historically one of the most heavily infected areas in the country. The vectors of Onchocerca volvulus are mainly Simulium damnosum complex blackflies, but a species of the Simulium neavei group may also contribute to transmission in some areas. The only detailed studies of parasite transmission in Mahenge were conducted in the late 1960s. The taxonomy of the S. damnosum complex has since been revised and onchocerciasis control through annual community directed treatment with ivermectin (CDTI) commenced in 1997. This study aimed to provide a cytogenetic and molecular update of the S. damnosum complex cytoforms present in Mahenge, and to evaluate the current status of O. volvulus transmission by blackflies following 19 years of annual CDTI. Rivers were surveyed to identify sites of S. damnosum s.l. breeding among the eastern slopes of the mountains, and human landing collections of adult female blackflies were made close to breeding sites. Identification of S. damnosum complex cytoforms was by cytotaxonomy of late-instar larvae and ITS1 amplicon size polymorphisms of larvae and adults. Adult blackflies were pool screened for O. volvulus infection using a triplex real-time PCR. The cytoforms 'Nkusi', Simulium kilibanum and 'Turiani' were found breeding in perennial rivers. 'Nkusi' and S. kilibanum were collected on human bait at 7/7 catch sites and possessed ITS1 profiles most closely resembling the molecular forms 'Nkusi J' and S. kilibanum 'T'. Whereas 'Turiani' was present in rivers, it was not collected on human bait and appears to be zoophilic. Simulium nyasalandicum was collected in low numbers on human bait at 3/7 catch sites. In total, 12,452 S. damnosum s.l. were pool screened and O. volvulus infection was detected in 97/104 pools of bodies and 51/104 pools of heads. The estimated percentage of S. damnosum s.l. carrying infective L3 stage parasites was 0.57% (95% CI 0.43%-0.74%). Onchocerca volvulus transmission by S. damnosum s.l. is continuing in the Mahenge Mountains after 19 years of annual CDTI. Infection rates appear similar to those reported in the 1960s, but a more detailed study is required to fully understand the epidemiological significance of the ongoing transmission. These results provide further evidence that annual CDTI may be insufficient to eliminate the parasite in formerly hyperendemic foci

From a long‑distance threat to the invasion front : a review of the invasive Aedes mosquito species in Belgium between 2007 and 2020

Author contributions ID drafted the manuscript and revised it after comments of all co-authors. ID, TVL, KDW and AV carried out the mosquito identifications. ID, KDW, AS, AV, IV, JDW, JD, TVL and WVB collected data in the field and sorted the mosquitoes in the laboratory. WVB, ID and KDW managed the data. NS and JDW performed the DNA barcoding. WD and AV produced the morphological reference collection. WVB, ID, MM and RM coordinated the projects. MK performed the statistical analysis. All authors critically reviewed the manuscript. All authors read and approved the final manuscript.Data supporting the conclusions of this article are included within the article and its additional file. The datasets generated and analysed during the current study are available in the GBIF repository [44–50].ADDITIONAL FILE 1: TABLE S1. Overview of the trapping methods used to monitor invasive mosquito species (IMS) in Belgium during the different years (and projects) and in different risk scenarios, indicating the number of traps or larval sampling visits per site and the frequency of trapping or larval sampling. TABLE S2. Aedes albopictus detections in Belgium between 2007 and 2020 at the ten points of entry (PoEs) per year including the sampling perimeter, collection and detection methods, collection (light grey) and detection (dark grey) period, control measures (X), number of individuals (total, females, males, larvae and eggs) and project. TABLE S3. Aedes japonicus detections in Belgium between 2007 and 2020 at the four points of entry (PoEs) per year including the sampling perimeter, collection and detection methods, collection (light grey) and detection (dark grey) period, the control measures (X), number of individuals (total, females, males, larvae and eggs) and project. TABLE S4. Aedes koreicus detections in Belgium between 2007 and 2020 at the two points of entry (PoEs) per year including the sampling perimeter, collection and detection methods, collection (light grey) and detection (dark grey) period, control measures (X), number of individuals (total, females, males, larvae and eggs) and project.Invasive mosquito species (IMS) and their associated mosquito-borne diseases are emerging in Europe. In Belgium, the first detection of Aedes albopictus (Skuse 1894) occurred in 2000 and of Aedes japonicus japonicus (Theobald 1901) in 2002. Early detection and control of these IMS at points of entry (PoEs) are of paramount importance to slow down any possible establishment. This article reviews the introductions and establishments recorded of three IMS in Belgium based on published (2007–2014) and unpublished (2015–2020) data collected during several surveillance projects. In total, 52 PoEs were monitored at least once for the presence of IMS between 2007 and 2020. These included used tyre and lucky bamboo import companies, airports, ports, parking lots along highways, shelters for imported cutting plants, wholesale markets, industrial areas, recycling areas, cemeteries and an allotment garden at the country border with colonised areas. In general, monitoring was performed between April and November. Mosquitoes were captured with adult and oviposition traps as well as by larval sampling. Aedes albopictus was detected at ten PoEs, Ae. japonicus at three PoEs and Aedes koreicus (Edwards 1917) at two PoEs. The latter two species have established overwintering populations. The percentage of PoEs positive for Ae. albopictus increased significantly over years. Aedes albopictus is currently entering Belgium through lucky bamboo and used tyre trade and passive ground transport, while Ae. japonicus through used tyre trade and probably passive ground transport. In Belgium, the import through passive ground transport was first recorded in 2018 and its importance seems to be growing. Belgium is currently at the invasion front of Ae. albopictus and Ae. japonicus. The surveillance and control management actions at well-known PoEs associated to long-distance introductions are more straightforward than at less-defined PoEs associated with short-distance introductions from colonised areas. These latter PoEs represent a new challenge for IMS management in Belgium in the coming years. Aedes albopictus is expected to become established in Belgium in the coming years, hence increasing the likelihood of local arbovirus transmission. The implementation of a sustainable, structured and long-term IMS management programme, integrating active and passive entomological surveillance, vector control and Public Health surveillance is therefore pivotal.The MODIRISK project (2007–2010) was funded by the Belgian Science Policy Programs; the EXOSURV project (2012) by the Federal, Flemish, Walloon and Brussels Capital region governments, the FASFC project (2013–2016) by the Federal Agency for the Safety of the Food Chain (FASFC), the MEMO and MEMO+2020 projects (2017–2020) by the Flemish, Walloon and Brussels regional governments and the Federal Public Service (FPS) Public Health, Food Chain Safety and Environment in the context of the National Environment and Health Action Plan (NEHAP) (Belgium), and the DiMoc project by the 2018–2019 BiodivERsA3 ERA-Net COFUND programme with the funding organisation FWO. The Barcoding Facility for Organisms and Tissues of Policy Concern is financed by the Belgian Science Policy Office (Belspo) as Belgian federal in-kind contribution to the European Research Infrastructure Consortium “LifeWatch”. The Outbreak Research Team of the Institute of Tropical Medicine is financially supported by the Department of Economy, Science and Innovation of the Flemish government.https://parasitesandvectors.biomedcentral.comam2023Veterinary Tropical Disease

The sonic hedgehog signaling pathway and the development of pharyngeal arch Derivatives in Haplochromis piceatus, a Lake Victoria cichlid

Objectives Pharyngeal arches develop in the head and neck regions, and give rise to teeth, oral jaws, the hyoid bone, operculum, gills, and pharyngeal jaws in teleosts. In this study, the expression patterns of genes in the sonic hedgehog (shh), wnt, ectodysplasin A (eda), and bone morphogenetic protein (bmp) pathways were investigated in the pharyngeal arches of Haplochromis piceatus, one of the Lake Victoria cichlids. Furthermore, the role of the shh pathway in pharyngeal arch development in H. piceatus larvae was investigated. Methods The expression patterns of lymphocyte enhancer binding factor 1 (lef1), ectodysplasin A receptor (edar), shh, patched 1 (ptch1), bmp4, sp5 transcription factor (sp5), sclerostin domain containing 1a (sostdc1a), and dickkopf 1 (dkk1) were investigated in H. piceatus larvae by in situ hybridization. The role of the shh pathway was investigated through morphological phenotypic characterization after its inhibition. Results We found that lef1, edar, shh, ptch1, bmp4, dkk1, sostdc1a, and sp5 were expressed not only in the teeth, but also in the operculum and gill filaments of H piceatus larvae. After blocking the shh pathway using cyclopamine, we observed ectopic shh expression and the disappearance of ptch1 expression. After six weeks of cyclopamine treatment, an absence of teeth in the oral upper jaws and a poor outgrowth of premaxilla, operculum, and gill filaments in juvenile H. piceatus were observed. Conclusions These results suggest that the shh pathway is important for the development of pharyngeal arch derivatives such as teeth, premaxilla, operculum, and gill filaments in H. piceatus

A new tool for the molecular identification of Culicoides species of the Obsoletus group: the glass slide microarray approach

Culicoides species of the Obsoletus group (Diptera: Ceratopogonidae) are potential vectors of bluetongue virus serotype 8 (BTV 8), which was introduced into central Western Europe in 2006. Correct morphological species identification of Obsoletus group females is especially difficult and molecular identification is the method of choice. In this study we present a new molecular tool based on probe hybridization using a DNA microarray format to identify Culicoides species of the Obsoletus group. The internal transcribed spacer 1 (ITS1) gene sequences of 55 Culicoides belonging to 13 different species were determined and used, together with 19 Culicoides ITS1 sequences sourced from GenBank, to design species-specific probes for the microarray test. This test was evaluated using the amplified ITS1 sequences of another 85 Culicoides specimens, belonging to 11 species. The microarray test successfully identified all samples (100%) of the Obsoletus group, identifying each specimen to species level within the group. This test has several advantages over existing polymerase chain reaction (PCR)-based molecular tools, including possible capability for parallel analysis of many species, high sensitivity and specificity, and low background signal noise. Hand-spotting of the microarray slide and the use of detection chemistry make this alternative technique affordable and feasible for any diagnostic laboratory with PCR facilities

Esperanza Window Traps for the collection of anthropophilic blackflies (Diptera: Simuliidae) in Uganda and Tanzania

There is an increasing need to evaluate the impact of chemotherapeutic and vector-based interventions as onchocerciasis affected countries work towards eliminating the disease. The Esperanza Window Trap (EWT) provides a possible alternative to human landing collections (HLCs) for the collection of anthropophilic blackflies, yet it is not known whether current designs will prove effective for onchocerciasis vectors throughout sub-Saharan Africa. EWTs were deployed for 41 days in northern Uganda and south eastern Tanzania where different Simulium damnosum sibling species are responsible for disease transmission. The relative efficacy of EWTs and HLCs was compared, and responses of host-seeking blackflies to odour baits, colours, and yeast-produced CO2 were investigated. Blue EWTs baited with CO2 and worn socks collected 42.3% (2,393) of the total S. damnosum s.l. catch in northern Uganda. Numbers were comparable with those collected by HLCs (32.1%, 1,817), and higher than those collected on traps baited with CO2 and BG-Lure (25.6%, 1,446), a synthetic human attractant. Traps performed less well for the collection of S. damnosum s.l. in Tanzania where HLCs (72.5%, 2,432) consistently outperformed both blue (16.8%, 563) and black (10.7%, 360) traps baited with CO2 and worn socks. HLCs (72.3%, 361) also outperformed sock-baited (6.4%, 32) and BG-Lure-baited (21.2%, 106) traps for the collection of anthropophilic Simulium bovis in northern Uganda. Contrasting blackfly distributions were observed on traps in Uganda and Tanzania, indicating differences in behaviour in each area. The success of EWT collections of S. damnosum s.l. in northern Uganda was not replicated in Tanzania, or for the collection of anthropophilic S. bovis. Further research to improve the understanding of behavioural responses of vector sibling species to traps and their attractants should be encouraged

Esperanza Window Traps for the collection of anthropophilic blackflies (Diptera: Simuliidae) in Uganda and Tanzania. S1 Table. Trap data.

Trap data associated with a paper titled "Esperanza Window Traps for the collection of anthropophilic blackflies (Diptera: Simuliidae) in Uganda and Tanzania" This dataset is made available as a Microsoft Excel file and hosted in the Figshare repository