Molecular monitoring of insecticide resistance in major disease vectors in Armenia.

BACKGROUND: Armenia is considered particularly vulnerable to life-threatening vector-borne diseases (VBDs) including malaria, West Nile virus disease and leishmaniasis. However, information relevant for the control of the vectors of these diseases, such as their insecticide resistance profile, is scarce. The present study was conducted to provide the first evidence on insecticide resistance mechanisms circulating in major mosquito and sand fly populations in Armenia. METHODS: Sampling sites were targeted based mainly on previous historical records of VBD occurrences in humans and vertebrate hosts. Initially, molecular species identification on the collected vector samples was performed. Subsequently, molecular diagnostic assays [polymerase chain reaction (PCR), Sanger sequencing, PCR-restriction fragment length polymorphism (RFLP), quantitative PCR (qPCR)] were performed to profile for major insecticide resistance mechanisms, i.e. target site insensitivity in voltage-gated sodium channel (vgsc) associated with pyrethroid resistance, acetylcholinesterase (ace-1) target site mutations linked to organophosphate (OP) and carbamate (CRB) resistance, chitin synthase (chs-1) target site mutations associated with diflubenzuron (DFB) resistance and gene amplification of carboxylesterases (CCEs) associated with resistance to the OP temephos. RESULTS: Anopheles mosquitoes were principally represented by Anopheles sacharovi, a well-known malaria vector in Armenia, which showed no signs of resistance mechanisms. Contrarily, the knockdown resistance (kdr) mutations V1016G and L1014F/C in the vgsc gene were detected in the arboviral mosquito vectors Aedes albopictus and Culex pipiens, respectively. The kdr mutation L1014S was also detected in the sand fly, vectors of leishmaniasis, Phlebotomus papatasi and P. tobbi, whereas no mutations were found in the remaining collected sand fly species, P. sergenti, P. perfiliewi and P. caucasicus. CONCLUSIONS: This is the first study to report on molecular mechanisms of insecticide resistance circulating in major mosquito and sand fly disease vectors in Armenia and highlights the need for the establishment of systematic resistance monitoring practices for the implementation of evidence-based control applications.

Assessing the Adoption of One Health Approaches in National Plans to Combat Health Threats: The Pilot of a One Health Conceptual Framework in Armenia.

Due to several factors, such as environmental and climate changes, the risk of health threats originating at the human-animal-environment interface, including vector-borne diseases (VBDs) and zoonoses, is increasing. Low-resource settings struggle to counter these multidimensional risks due to their already-strained health systems and are therefore disproportionally affected by the impact caused by these changes. Systemic approaches like One Health (OH) are sought to strengthen prevention and preparedness strategies by addressing the drivers of potential threats with a multidisciplinary and multisectoral approach, considering the whole system at the human-animal-environment interface. The integration of OH in national plans can be challenging due to the lack of effective coordination and collaboration among different sectors. To support the process of knowledge coproduction about the level of OH integration in prevention and preparedness strategies against health threats in Armenia, a situation analysis was performed on Crimean-Congo hemorrhagic fever/virus and anthrax (identified by local stakeholders as priorities to be addressed with the OH approach), and actions to strengthen the national OH system were identified with the support of a OH conceptual framework. The study highlighted that multidisciplinary and multisectoral efforts towards prevention and preparedness against VBDs and zoonoses threats need to be strengthened in Armenia, and priority actions to integrate the OH approach were identified.

Gamasid Ticks as Vectors of Tularemia in the Southeast of Armenia.

Background: The natural environment of southeastern Armenia, which includes the Syunik and Vayots Dzor regions, provides a high biodiversity of flora and fauna, including ectoparasites. Currently, the fauna and ecology of gamasid ticks and their role in the circulation of tularemia in this area are unclear and incomplete. To better understand the persistence of tularemia in Armenia, an assessment of specific hosts and their vectors is needed to evaluate their role in perpetuating tularemia. Materials and Methods: Utilizing data and samples collected from 1970 to 2020, we have evaluated the species composition of gamasid ticks found on the common vole and in their nests and burrows, and identified the presence of tularemia over time. We evaluated five different geographical landscapes: semidesert, dry mountain steppe, mountain steppe, mountain forest, and high mountain in the communities and open areas of Kapan, Goris, Sisian, Meghri, and Jermuk. Results: We determined the density of gamasid ticks in southeastern Armenia over the 50-year period and isolated 20 cultures of tularemia in 12 separate years. Conclusions: It is important to regularly monitor gamasid ticks in southeastern Armenia to clarify the risk factors for the occurrence of tularemia epizootics, among both carriers and vectors, to better understand the full epidemiological picture.

Assessment of expertise in morphological identification of mosquito species (Diptera, Culicidae) using photomicrographs.

Accurate identification of insect species is an indispensable and challenging requirement for every entomologist, particularly if the species is involved in disease outbreaks. The European MediLabSecure project designed an identification (ID) exercise available to any willing participant with the aim of assessing and improving knowledge in mosquito taxonomy. The exercise was based on high-definition photomicrographs of mosquitoes (26 adult females and 12 larvae) collected from the western Palaearctic. Sixty-five responses from Europe, North Africa and the Middle East were usable. The study demonstrated that the responders were better at identifying females (82% correct responses) than larvae (63%). When the responders reported that they were sure of the accuracy of their ID, the success rate of ID increased (92% for females and 88% for larvae). The top three tools used for ID were MosKeyTool (72% of responders), the ID key following Becker et al. [2010. Mosquitoes and their control, 2nd edn. Berlin: Springer] (38%), and the CD-ROM of Schaffner et al. [2001. Les moustiques d'Europe: logiciel d'identification et d'enseignement - The mosquitoes of Europe: an identification and training programme. Montpellier: IRD; EID] (32%), while other tools were used by less than 10% of responders. Responders reporting the identification of mosquitoes using the MosKeyTool were significantly better (80% correct responses) than non-MosKeyTool users (69%). Most responders (63%) used more than one ID tool. The feedback from responders in this study was positive, with the exercise being perceived as halfway between educational training and a fun quiz. It raised the importance of further expanding training in mosquito ID for better preparedness of mosquito surveillance and control programmes.

Title: Évaluation de l'expertise en identification morphologique des espèces de moustiques (Diptera, Culicidae) à l'aide de photomicrographies. Abstract: L'identification précise des espèces d'insectes est une exigence indispensable et difficile pour tout entomologiste, en particulier si l'espèce est impliquée dans des épidémies. Le projet européen MediLabSecure a conçu un exercice d'identification (ID) accessible à tout participant volontaire dans le but d'évaluer et d'améliorer les connaissances en taxonomie des moustiques. L'exercice était basé sur des photomicrographies haute définition de moustiques (26 femelles adultes et 12 larves) prélevées dans le Paléarctique occidental. Soixante-cinq réponses d'Europe, d'Afrique du Nord et du Moyen-Orient ont été utilisables. L'étude a démontré que les répondants étaient meilleurs pour identifier les femelles (82 % de réponses correctes) que les larves (63 %). Lorsque les répondants ont déclaré être sûrs de l'exactitude de leur ID, le taux de réussite de l'identification était meilleur (92 % pour les femelles et 88 % pour les larves). Les trois principaux outils utilisés pour les ID étaient MosKeyTool (72 % des répondants), la clé d'identification du livre de Becker et al. (38%) et le CD-ROM de Schaffner et al. (32 %), tandis que d'autres outils étaient utilisés par moins de 10 % des répondants. Les répondants déclarant identifier des moustiques à l'aide de MosKeyTool étaient significativement meilleurs (80 % de réponses correctes) que les non-utilisateurs de MosKeyTool (69 %). La plupart des répondants (63 %) ont utilisé plus d'un outil d'identification. Les commentaires des répondants de cette étude ont été positifs, l'exercice étant perçu comme à mi-chemin entre une formation pédagogique et un quiz amusant. Il a souligné l'importance d'étendre la formation complémentaire à l'identification des moustiques pour une meilleure préparation des programmes de surveillance et de contrôle des moustiques.

The mosquitoes of Armenia: review of knowledge and results of a field survey with first report of Aedes albopictus.

BACKGROUND: In 2016, a field study was implemented in all Armenian provinces in order to update knowledge on the presence and distribution of both native and invasive mosquito species. Larvae and adult mosquitoes were sampled and identified on the basis of their morphology. Supplementary field surveys were performed in 2017-2018. RESULTS: Between June 20 and July 12, 2016, 117 localities were visited. A total number of 197 sampling units were checked, of which 143 (73%) were positive for mosquitoes (with 1-6 species per sampling unit). A total number of 4157 mosquito specimens were identified to species or species complex level. Ten species represent first records for Armenia: Aedes albopictus, Ae. annulipes, Ae. cataphylla, Ae. cinereus/geminus (probably Ae. cinereus), Ae. flavescens, Anopheles plumbeus, Coquillettidia richiardii, Culex martinii, Cx. torrentium and Culiseta subochrea. The invasive species Ae. albopictus was recorded in a single locality (Bagratashen) at the border point with Georgia, along the main road Tbilisi-Yerevan. This species was further recorded in 2017 and 2018, demonstrating its establishment and spread in north Armenia. These surveys confirm the presence of vectors of malaria parasites (in particular An. sacharovi) and West Nile virus (Cx. pipiens). CONCLUSION: The knowledge of the Armenian mosquito fauna is extended to a list of 28 species. The record of Aedes albopictus, an important potential vector of many arboviruses, has important implications for public health.

TITLE: Les moustiques d'Arménie : synthèse des connaissances et résultats d'une étude de terrain avec une première mention pour Aedes albopictus. ABSTRACT: Contexte : En 2016, nous avons réalisé une étude sur le terrain dans toutes les provinces du pays dans le but d'actualiser la présence et la distribution des espèces de moustiques aussi bien natives qu'invasives. Les moustiques récoltés aux stades larvaires et adultes ont été identifiés sur des critères morphologiques. Des suivis additionnels ont été réalisés en 2017 et 2018. Résultats : Entre le 20 juin et le 12 juillet 2016, 117 localités ont été visitées. Au total, 197 unités de collecte ont été prospectées dont 143 (73%) se sont révélées positives pour les moustiques (avec de 1 à 6 espèces par unité de collecte). Au total, 4157 spécimens ont été identifiés au niveau de l'espèce ou du complexe d'espèces. Dix espèces ont été observées pour la première fois en Arménie : Aedes albopictus, Ae. annulipes, Ae. cataphylla, Ae. cinereus/geminus (probablement Ae. cinereus), Ae. flavescens, Anopheles plumbeus, Coquillettidia richiardii, Culex martinii, Cx. torrentium et Culiseta subochrea. L'espèce invasive Ae. albopictus a été observée dans une seule localité (Bagratashen) à la frontière avec la Géorgie, sur l'axe routier principal Tbilisi-Yerevan. Cette espèce a également été observée en 2017 et en 2018, faisant la preuve de son installation et de sa diffusion dans le nord de l'Arménie. Ces suivis confirment la présence des vecteurs de Plasmodium humains (en particulier An. sacharovi) et du virus West Nile (Cx. pipiens). Conclusion : La connaissance de la faune culicidienne d'Arménie progresse, avec une liste actualisée à 28 espèces. L'observation d'Aedes albopictus, un important vecteur potentiel de nombreux arbovirus, a d'importantes implications en termes de santé publique.