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BackgroundAfter the unprecedented Zika virus (ZIKV) outbreak in the western hemisphere from 2015-2018, Aedes aegypti and Ae. albopictus are now well established primary and secondary ZIKV vectors, respectively. Consensus about identification and importance of other secondary ZIKV vectors remain. This systematic review aims to provide a list of vector species capable of transmitting ZIKV by reviewing evidence from laboratory vector competence (VC) studies and to identify key knowledge gaps and issues within the ZIKV VC literature.MethodsA search was performed until 15th March 2022 on the Cochrane Library, Lilacs, PubMed, Web of Science, WHOLIS and Google Scholar. The search strings included three general categories: 1) "ZIKA"; 2) "vector"; 3) "competence", "transmission", "isolation", or "feeding behavior" and their combinations. Inclusion and exclusion criteria has been predefined and quality of included articles was assessed by STROBE and STROME-ID criteria.FindingsFrom 8,986 articles retrieved, 2,349 non-duplicates were screened by title and abstracts,103 evaluated using the full text, and 45 included in this analysis. Main findings are 1) secondary vectors of interest include Ae. japonicus, Ae. detritus, and Ae. vexans at higher temperature 2) Culex quinquefasciatus was not found to be a competent vector of ZIKV, 3) considerable heterogeneity in VC, depending on the local mosquito strain and virus used in testing was observed. Critical issues or gaps identified included 1) inconsistent definitions of VC parameters across the literature; 2) equivalency of using different mosquito body parts to evaluate VC parameters for infection (mosquito bodies versus midguts), dissemination (heads, legs or wings versus salivary glands), and transmission (detection or virus amplification in saliva, FTA cards, transmission to neonatal mice); 3) articles that fail to use infectious virus assays to confirm the presence of live virus; 4) need for more studies using murine models with immunocompromised mice to infect mosquitoes.ConclusionRecent, large collaborative multi-country projects to conduct large scale evaluations of specific mosquito species represent the most appropriate approach to establish VC of mosquito species.

The sterile insect technique (SIT) involves releasing large numbers of sterile males to outcompete wild males in mating with females, leading to a decline in pest populations. In the current study, we conducted a suppression trial in Greece against the invasive dengue vector mosquito Aedes albopictus (Skuse) through the weekly release of sterile males for 22 weeks from June to September 2019. Our approach included the long-distance transport of sterile mosquitoes, and their release at a density of 2,547 ± 159 sterile males per hectare per week as part of an area-wide integrated pest management strategy (AW-IPM). The repeated releases of sterile males resulted in a gradual reduction in egg density, reaching 78% from mid-June to early September. This reduction remained between 70% and 78% for four weeks after the end of the releases. Additionally, in the SIT intervention area, the ovitrap index, representing the percentage of traps containing eggs, remained lower throughout the trial than in the control area. This trial represents a significant advance in the field of mosquito control, as it explores the viability and efficacy of producing and transporting sterile males from a distant facility to the release area. Our results provide valuable insights for future SIT programmes targeting Ae. Albopictus, and the methodology we employed can serve as a starting point for developing more refined and effective release protocols, including the transportation of sterile males over long distances from production units to intervention areas.

Simple Summary: The study is about tracking different types of mosquitoes and the spread of the invasive Asian tiger mosquito on the remote Greek island of Kastellorizo. The research aims to understand how widespread these mosquitoes are and how prepared the local community is to deal with them. We conducted KAP (knowledge, attitude, practices) surveys, set up mosquito traps, and identified the types of mosquitoes found. The surveys revealed the need for increased public education about these health risks. The mosquito traps confirmed the presence of species such as Aedes albopictus, which can play a role in the spread of various diseases, along with other species like Culex pipiens, which is the main vector of West Nile virus. The study concludes that involving the community in mosquito monitoring is crucial in regard to helping control the mosquito population. These findings are valuable because they provide essential information for creating effective mosquito control strategies in isolated areas, ultimately helping to protect public health by reducing the risk of disease outbreaks. The expansion of the tiger mosquito, a vector that can transmit diseases such as dengue, chikungunya, and Zika virus, poses a growing threat to global health. This study focuses on the entomological surveillance of Kastellorizo, a remote Greek island affected by its expansion. This research employs a multifaceted approach, combining KAP survey (knowledge, attitude, practices), mosquito collection using adult traps and human landing catches, and morphological and molecular identification methods. Results from questionnaires reveal community awareness and preparedness gaps, emphasizing the need for targeted education. Mosquito collections confirm the presence of the Aedes albopictus, Aedes cretinus, and Culex pipiens mosquitoes, highlighting the importance of surveillance. This study underscores the significance of community engagement in entomological efforts and proposes a citizen science initiative for sustained monitoring. Overall, this research provides essential insights for developing effective mosquito control programs in remote island settings, thereby emphasizing the importance of adopting a One Health approach to mitigate the spread of vector-borne diseases. [ABSTRACT FROM AUTHOR]

Aedes aegypti, the yellow fever mosquito and Aedes albopictus, the tiger mosquito, continue to expand their geographical distribution, reshaping the European epidemiological risks for mosquito-borne diseases. The reintroduction of Aedes aegypti near the airport and port in Larnaka and the detection of Aedes albopictus near the marina and old port of the Limassol area in Cyprus are reported herein. The measures taken to investigate these events included (i) communication to health authorities, (ii) expert on-site visits and verification of findings, (iii) enhanced active surveillance, and (iv) development of an Emergency Action Plan followed by a Contingency Plan. These emergency action plans were developed to delimitate the infested areas and to prevent the spreading of the mosquito populations into new areas. The general principles are presented along with their rationale to serve as guidelines for other geographical regions targeting suppression/eradication with a sterile insect technique component. In parallel, this manuscript serves as a call for action at the European level to impede the further spread of these species and support the activities being undertaken in Cyprus to combat the incursions of Aedes invasive species.

Ceratitis capitata (Wiedemann), also known as the Mediterranean fruit fly, is one of the most serious pests for several fresh fruit commodities causing extensive fruit losses worldwide. The response of C. capitata adults to fruit and nonfruit volatiles has been extensively studied. However, the linkage between fruit volatiles and the female ovipositional choice has not been fully elucidated. The present study focused on identifying the volatile organic compounds emitted by detached intact fresh fruits (oranges, lemons, bergamots, and apples) and citrus essential oils and evaluate their effect on Mediterranean fruit fly oviposition. There were more than 130 and 45 volatiles compounds detected in fruits odors and citrus essential oils, respectively. The volatile profile of fruits was dominated either from terpenes and terpenoids or from esters of butanoic, hexanoic, and octanoic acids while limonene was by far the most abundant compound in all citrus essential oils. Oviposition of C. capitata was strongly affected by volatiles emanated from both intact fruit and the citrus essential oils. Regarding the volatiles of the intact fruits, the odor of sweet orange elicited strong oviposition responses to females, while bergamot had the least stimulatory effect on oviposition. Bergamot oil also elicited the least oviposition stimulation compared to sweet orange and lemon essential oils. Our discussion elaborates on the role of fruit volatiles on host finding behavior and fruit susceptibility to C. capitata infestation and includes possible practical implication of the above findings. [ABSTRACT FROM AUTHOR]

Τhe essential oils contained in the rind of the fruit and the leaves of bergamot from Greece (Citrus aurantium subsp. bergamia) were studied. The bergamot trees in question were cultivated on Kefalonia Island. The plant material (leaves and fruits in different stages of maturity) was collected between December and March for a two year period. The rind of the fruit was separated manually and the essential oil was obtained either by cold pressing or by hydrodistillation. The maximum yield calculated on a wet weight of fresh rinds basis was 1.8%. The essential oils were first analyzed by GC-MS with a DB-5 column and then with a β-Dex™ enantiomeric column. The main constituent of the cold pressed essential oil of the rind was (–)-linalyl acetate with optical purity >99.9%. Other important constituents were (–)-linalool, (+)-limonene and γ-terpinene. The best value of linalool/linalyl acetate ratio was 0.38 and the maximum sum of linalool+linalyl acetate was found to be 55.8%. The larvacidal activities of the obtained essential oils and the compounds (±)-linalyl acetate, (±)-linalool and (–)-linalool were evaluated against larvae of the mosquito species Culex pipiens (Diptera: Culicidae), the West Nile virus vector, under laboratory conditions. The cold pressed essential oil showed an LC50 value of 58 mg/L, while the LC50 value of the corresponding essential oil obtained by hydrostillation was 106 mg/L. The essential oil of the leaves presented similar larvicidal toxicity with the cold pressed oil of the rind (LC50=68 mg/L).

Thaumetopoea pityocampa, the winter pine processionary moth, is one of the most important pests of pine trees in the Mediterranean region. To learn more about the refugial areas within the greater refugium of Greece, samples from 15 local populations were collected. Analysis of the Cytochrome Oxidase I region identified 15 haplotypes. One strongly supported clade was found, separating the Aegean island of Lesvos from the mainland populations. Mdiv analysis showed that this clade diverged from the general clade 155,000 y.a., suggesting the sea level changes during the Quaternary Period as a possible reason for its seclusion. Additionally, comparisons with similar studies in this region revealed a possible colonization of the eastern Aegean islands from the Turkish mainland rather than from Greece. However, no strong isolation-by-distance events were detected among the mainland populations, which could be attributed to the joint effect of regular gene flow and the lack of insurmountable geographic barriers. Finally, regarding population structure, Bayesian analysis as well as neutrality tests pointed towards an ongoing population expansion which verifies the potential invasiveness of this pest species, something that will have to be dealt with under the influence of climate change.