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O objeto de estudo desta dissertação é o cálculo do galgamento de uma estrutura de defesa longitudinal aderente situada na praia da Vagueira, em Aveiro. Trata-se de uma zona com graves problemas de erosão, onde, em condições de agitação marítima adversas, a segu-rança de pessoas e bens na sua retaguarda é posta em causa. A estrutura em estudo tem a particularidade de se encontrar numa zona de baixa pro-fundidade, ficando por vezes totalmente emersa. Tendo em conta as suas características foram utilizadas as seguintes fórmulas para estimar o caudal de galgamento: • Eurotop (2018)- Main Value Approach; • Eurotop (2018)- Design Approach; • Goda (2009); • Goda (2009) modificado por Altomare et al. (2020); • Van Gent et al. (2016); • Van Gent et al. (2016) modificado por Altomare et al. (2020); • Mase et al. (2013), com hb/Hm0 segundo Kirby e Mase; • Mase et al. (2013), com hb=Hm0/0,6. Para o cálculo do galgamento foram utilizados dados de agitação marítima registados de 6 em 6 horas, entre 1979 e 2018, o que corresponde a um total de 58.076 casos. A maioria das fórmulas utilizadas necessita do perfil do fundo do mar para estimar o caudal de galgamento. No caso em estudo, existe uma barra e uma fossa no perfil transversal do fundo do mar, localizadas em frente à estrutura, característica esta que tem influência no comportamento da onda. No entanto, na aplicação das fórmulas é necessário que o perfil seja sempre crescente. Por esse motivo foram criados quatro perfis diferentes, sempre crescentes, adaptados do perfil original. Ao aplicar estes perfis em todas as fórmulas utilizadas, verificou-se que a existência da barra origina caudais de galgamento superiores. Por esse motivo, deve ser tida em conta em fins de projeto e dimensionamento, uma vez que a sua inexistência pode influenciar a estimativas de galgamento inferiores às reais. Em relação às fórmulas utilizadas, as duas abordagens de Goda foram as que origina-ram resultados menos consensuais, visto que estimaram caudais de galgamento muito supe-riores às das outras fórmulas utilizadas e não espectáveis na zona em estudo. As restantes obtiveram resultados dentro da mesma gama de valores, embora quando comparadas entre si, seja evidente alguma divergência nos resultados obtidos. Por fim, verificou-se que os caudais máximos de galgamento são provocados por uma condição de agitação média com altura de onda significativa de 4,46m, um período de pico de 17,8s, direção de 284º e um nível do mar de 3,55m, o que associa os maiores caudais de galga-mento à verificação, em simultâneo, de condições de agitação muito energéticas e níveis de mar correspondentes a preia mar. The object of study of this dissertation is the calculation of the mean overtopping dis-charge of a seawall located at Vagueira beach, in Aveiro. This is an area with serious erosion problems, where, in adverse maritime conditions, the safety of people and goods in its rear is compromised. The structure under study has the particularity of being in a very shallow area, some-times being completely out of water. Considering its characteristics, the following formulas were used to estimate the overtopping flow: • Eurotop (2018)- Main Value Approach; • Eurotop (2018)- Design Approach; • Goda (2009); • Goda (2009) modified by Altomare et al. (2020); • Van Gent et al. (2016); • Van Gent et al. (2016) modified by Altomare et al. (2020); • Mase et al. (2013), with hb/Hm0 according to Kirby and Mase; • Mase et al. (2013), with hb=Hm0/0,6. To calculate the mean overtopping discharge, sea agitation data recorded every 6 hours between 1979 and 2018 were used, corresponding to a total of 58,076 cases. Most of the formulas used need the seabed profile to estimate the overtopping. In the case under study, there is a bar and a pit in the transverse seabed profile, located in front of the structure, a characteristic that has an influence on the wave behaviour. However, in the formula application, it is necessary that the profile is always increasing. For this reason four different profiles were created, always increasing, adapted from the original profile. By ap-plying these profiles in all the formulas used, it was found that the existence of the bar in-creases the mean overtopping discharge over the structure. For this reason, for design and dimensioning purposes, the bar should be taken into account, since its inexistence can lead to overtopping estimates lower than the real ones. Regarding the formulas used, Goda's two approaches were the ones that gave rise to less consensual results, as they estimated much higher overtopping flows, not expected in that zone. The others obtained results within the same range of values, although when compared, some divergence in the results obtained is evident. Finally, it was found that the maximum mean overtopping discharge occurred for a wave condition with significant wave height of 4.46m, peak period of 17.8s, average direction of 284º and an sea level of 3 .55m. In other words, the highest mean overtopping discharge is associated to, simultaneously occurrence of strong energetic wave and a high sea level.

The release of modified mosquitoes to suppress/replace vectors constitutes a promising tool for vector control and disease prevention. Evidence regarding these innovative modification techniques is scarce and disperse. This work conducted a systematic review, gathering and analysing research articles from PubMed and Biblioteca Virtual em Saúde databases whose results report efficacy and non-target effects of using modified insects for disease prevention, until 2016. More than 1500 publications were screened and 349 were analysed. Only 12/3.4% articles reported field-based evidence and 41/11.7% covered modification strategies’ post-release efficacy. Variability in the effective results (90/25.7%) questioned its reproducibility in different settings. We also found publications reporting reversal outcomes 38/10.9%, (e.g. post-release increase of vector population). Ecological effects were also reported, such as horizontal transfer events (54/15.5%), and worsening pathogenesis induced by natural wolbachia (10/2.9%). Present work revealed promising outcomes of modifying strategies. However, it also revealed a need for field-based evidence mainly regarding epidemiologic and long-term impact. It pointed out some eventual irreversible and important effects that must not be ignored when considering open-field releases, and that may constitute constraints to generate the missing field evidence. Present work constitutes a baseline of knowledge, offering also a methodological approach that may facilitate future updates., GRAPHICAL ABSTRACT

Made available in DSpace on 2019-10-04T12:35:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-02-19 FEDER - COMPETE Program Fundacao para a Ciencia e Tecnologia Project CMDT: Past and present population genetics of the vector Aedes aegypti: a tool for dengue control policies FCT Historically known as the yellow fever mosquito, Aedes aegypti invaded Madeira Island in 2005 and was the vector of the island's first dengue outbreak in 2012. We have studied genetic variation at 16 microsatellites and two mitochondrial DNA genes in temporal samples of Madeira Island, in order to assess the origin of the invasion and the population structure of this mosquito vector. Our results indicated at least two independent colonization events occurred on the island, both having a South American source population. In both scenarios, Venezuela was the most probable origin of these introductions, a result that is in accordance with the socioeconomic relations between this country and Madeira Island. Once introduced, Ae. aegypti has rapidly expanded along the southern coast of the island and reached a maximum effective population size (N-e) in 2012, coincident with the dengue epidemic. After the outbreak, there was a 10-fold reduction in N-e estimates, possibly reflecting the impact of community-based vector control measures implemented during the outbreak. These findings have implications for mosquito surveillance not only for Madeira Island, but also for other European regions where Aedes mosquitoes are expanding. Univ Nova Lisboa, Inst Higiene & Med Trop, Global Hlth & Trop Med, Lisbon, Portugal Univ Estadual Paulista, Inst Biociencias, Dept Parasitol, Botucatu, SP, Brazil Museum Nat Hist Funchal, RAM, Madeira, Portugal Univ Cent Venezuela, Inst Med Trop, Secc Entomol Med, Caracas, Venezuela IP RAM, Dept Saude Planeamento & Adm Geral, Inst Adm Saude & Assuntos Sociais, Funchal, Madeira, Portugal Madeira Reg Govt, Funchal, Madeira, Portugal Hlth & Social Affairs, Funchal, Madeira, Portugal Univ Estadual Paulista, Inst Biociencias, Dept Parasitol, Botucatu, SP, Brazil FEDER - COMPETE Program: PTDC/SAU-EPI/115853/2009 Fundacao para a Ciencia e Tecnologia: PTDC/SAU-EPI/115853/2009 Project CMDT: Past and present population genetics of the vector Aedes aegypti: a tool for dengue control policies: Pest-OE/SAU/LA0018/2011 FCT: SFRH/BD/98873/2013 FCT: SFRH/BPD/72532/2010 : GHTM-UID/Multi/04413/2013

In the wake of the ‘omics’ explosion of data, reverse vaccinology approaches are being applied more readily as an alternative for the discovery of candidates for next generation diagnostics and vaccines. Promising protective antigens for the control of ticks and tick-borne diseases can be discovered by mining available omics data for immunogenic epitopes. The present study aims to explore the previously obtained Rhipicephalus bursa sialotranscriptome during both feeding and Babesia infection, to select antigenic targets that are either membrane-associated or a secreted protein, as well as unique to the ectoparasite and not present in the mammalian host. Further, they should be capable of stimulating T and B cells for a potential robust immune response, and be non-allergenic or toxic to the host. From the R. bursa transcriptome, 5706 and 3025 proteins were identified as belonging to the surfaceome and secretome, respectively. Following a reverse genetics immunoinformatics pipeline, nine preferred candidates, consisting of one transmembrane-related and eight secreted proteins, were identified. These candidates showed a higher predicted antigenicity than the Bm86 antigen, with no homology to mammalian hosts and exposed regions. Only four were functionally annotated and selected for further in silico analysis, which examined their protein structure, surface accessibility, flexibility, hydrophobicity, and putative linear B and T-cell epitopes. Regions with overlapping coincident epitopes groups (CEGs) were evaluated to select peptides that were further analyzed for their physicochemical characteristics, potential allergenicity, toxicity, solubility, and potential propensity for crystallization. Following these procedures, a set of three peptides from the three R. bursa proteins were selected. In silico results indicate that the designed epitopes could stimulate a protective and long-lasting immune response against those tick proteins, reflecting its potential as anti-tick vaccines. The immunogenicity of these peptides was evaluated in a pilot immunization study followed by tick feeding to evaluate its impact on tick behavior and pathogen transmission. Combining in silico methods with in vivo immunogenicity evaluation enabled the screening of vaccine candidates prior to expensive infestation studies on the definitive ovine host animals.

Background: The frequency and intensity of arboviral epidemics is steadily increasing and posing an intractable public health burden. Current vector control methods are proving ineffectual and despite progress in the development of high technology approaches, there is an urgent need for the development of tools for immediate implementation. Several studies suggest that the auto-dissemination of pyriproxyfen (PPF) is a promising new approach to larviciding although there is little detail on the conditions under which it is optimally effective. Here, we evaluate the efficacy of the approach in urban and rural sites in Madeira, Portugal.Results: Auto-dissemination of PPF through adapted Biogents Sentinel traps (BGSTs) resulted in a modest but consistent impact on both juvenile and adult mosquito populations, but with considerable spatial heterogeneity. This heterogeneity was related to the distance from the BGST dissemination station as well as the local density of adult mosquitoes. There was evidence that the impact of PPF was cumulative over time both locally and with gradual spatial expansion.Conclusions: The density of adult mosquitoes and the spatial distribution of dissemination devices are key factors in mediating efficacy. In addition, urban topography may affect the efficiency of auto-dissemination by impeding adult mosquito dispersal. Further studies in a range of urban landscapes are necessary to guide optimal strategies for the implementation of this potentially efficacious and cost-effective approach to larviciding.

Sensitive techniques for the detection of Plasmodium (Aconoidasida: Plasmodiidae) sporozoites in field-collected malaria vectors are essential for the correct assessment of risk for malaria transmission. A real-time polymerase chain reaction (RT-PCR) protocol targeting Plasmodium mtDNA proved to be much more sensitive in detecting sporozoites in mosquitoes than the widely used enzyme-linked immunosorbent assay targeting Plasmodium circumsporozoite protein (CSP-ELISA). However, because of the relatively high costs associated with equipment and reagents, RT-PCRs are mostly used to assess the outcomes of experimental infections in the frame of research experiments, rather than in routine monitoring of mosquito infection in the field. The present authors developed a novel mtDNA-based nested PCR protocol, modified from a loop-mediated isothermal amplification (LAMP) assay for Plasmodium recognition in human blood samples, and compared its performance with that of routinely used CSP-ELISAs in field-collected Anopheles coluzzii (Diptera: Culicidae) samples. The nested PCR showed 1.4-fold higher sensitivity than the CSP-ELISA. However, nested PCR results obtained in two laboratories and in different replicates within the same laboratory were not 100% consistent, probably because the copy number of amplifiable Plasmodium mtDNA was close in some specimens to the threshold of nested PCR sensitivity. This implies that Plasmodium-positive specimens should be confirmed by a second nested PCR to avoid false positives. Overall, the results emphasize the need to use molecular approaches to obtain accurate estimates of the actual level of Plasmodium circulation within malaria vector populations.

Background Mosquito-borne viruses—such as Zika, chikungunya, dengue fever, and yellow fever, among others—are of global importance. Although vaccine development for prevention of mosquito-borne arbovirus infections has been a focus, mitigation strategies continue to rely on vector control. However, vector control has failed to prevent recent epidemics and arrest expanding geographic distribution of key arboviruses, such as dengue. As a consequence, there has been increasing necessity to further optimize current strategies within integrated approaches and advance development of alternative, innovative strategies for the control of mosquito-borne arboviruses. Methods and findings This review, intended as a general overview, is one of a series being generated by the Worldwide Insecticide resistance Network (WIN). The alternative strategies discussed reflect those that are currently under evaluation for public health value by the World Health Organization (WHO) and represent strategies of focus by globally recognized public health stakeholders as potential insecticide resistance (IR)-mitigating strategies. Conditions where these alternative strategies could offer greatest public health value in consideration of mitigating IR will be dependent on the anticipated mechanism of action. Arguably, the most pressing need for endorsement of the strategies described here will be the epidemiological evidence of a public health impact. Conclusions As the burden of mosquito-borne arboviruses, predominately those transmitted by Aedes aegypti and A. albopictus, continues to grow at a global scale, new vector-control tools and integrated strategies will be required to meet public health demands. Decisions regarding implementation of alternative strategies will depend on key ecoepidemiological parameters that each is intended to optimally impact toward driving down arbovirus transmission., Author summary International public health workers are challenged by the burden of arthropod-borne viral diseases, to include mosquito-borne arboviruses transmitted by Aedes aegypti and A. albopictus due in part to lack of sustainable vector control and insecticide resistance (IR), as well as the inability to scale up and sustain existing interventions for prevention of urban epidemics. As a consequence, there has been increasing interest to advance the development of alternative methods. This review provides a general overview of alternative vector-control strategies under development for the control of arbovirus mosquito vectors and highlights how each could offer innovative public health value. Considerations to regulations, acceptance, and sustainability are also provided.

International audience; Background Aedes spp. mosquitoes mainly transmit the arboviruses dengue virus (DENV) and chikungunya virus (CHIKV) in urban areas, causing a severe public health problem. In 2012-2013, a major dengue outbreak occurred on Madeira Island where the mosquito Aedes aegypti was the only vector. Up to now, the competence of Ae. aegypti populations from Madeira to transmit DENV or CHIKV remains unknown. This study aimed to assess experimentally the ability of Ae. aegypti populations from Madeira to transmit these viruses. Results: By orally exposing mosquitoes to CHIKV (NC/2011-568) and DENV-2 (Bangkok), the vector competence of two field-collected Ae. aegypti populations, i.e. Funchal and Paúl do Mar, was evaluated. We found that both populations were similarly infected and ensured the dissemination and transmission of CHIKV at the same rates. With DENV-2, viral dissemination was significantly higher in the Funchal population compared to Paúl do Mar. We found no significant differences in transmission rates between populations.ResultsBy orally exposing mosquitoes to CHIKV (NC/2011-568) and DENV-2 (Bangkok), the vector competence of two field-collected Ae. aegypti populations, i.e. Funchal and Paúl do Mar, was evaluated. We found that both populations were similarly infected and ensured the dissemination and transmission of CHIKV at the same rates. With DENV-2, viral dissemination was significantly higher in the Funchal population compared to Paúl do Mar. We found no significant differences in transmission rates between populations.ConclusionsTo our knowledge, this study has demonstrated for the first time the ability of temperate European Ae. aegypti populations from Madeira to transmit DENV and CHIKV. As our results suggest, there is a potential risk for the local transmission of DENV and CHIKV if introduced to Madeira or continental Europe where Aedes albopictus is present. Our results highlight the need for continuing vector surveillance and control on Madeira Island to future-proof the Island against mosquito-borne epidemics.

The extensive use of insecticides for vector control has led to the development of insecticide resistance in Aedes aegypti populations on a global scale, which has significantly compromised control actions. Insecticide resistance, and its underlying mechanisms, has been investigated in several countries, mostly in South American and Asian countries. In Africa, however, studies reporting insecticide resistance are rare and data on resistance mechanisms, notably knockdown resistance (kdr) mutations, is scarce. In this study, the recently described V410L kdr mutation is reported for the first time in old world Ae. aegypti populations, namely from Angola and Madeira island. Two additional kdr mutations, V1016I and F1534C, are also reported for the first time in populations from Angola and Cape Verde. Significant associations with the resistance phenotype were found for both V410L and V1016I individually as well as for tri-locus genotypes in the Angolan population. However, no association was found in Madeira island, probably due to the presence of a complex pattern of multiple insecticide resistance mechanisms in the local Ae. aegypti population. These results suggest that populations carrying the same kdr mutations may respond differently to the same insecticide, stressing the need for complementary studies when assessing the impact of kdr resistance mechanisms in the outcome of insecticide-based control strategies., Author summary One of the pillars for the prevention of Aedes-transmitted arboviral infections has been vector control, which is primarily based on the use of chemical insecticides. However, extensive use of insecticides has led to the development of insecticide resistance, undermining the sustainability of control programs. Mutations in the voltage-gated sodium channel gene have been associated with knockdown resistance in many insect species including Aedes aegypti. In Africa, in spite of the use of insecticides for vector control in many countries, data on insecticide resistance and its underlying mechanisms remain scarce. In this study, we report for the first time the occurrence of a recently described kdr mutation, V410L, in Old World Ae. aegypti from Angola and Madeira island. Two other kdr mutations, V1016I and F1534C, were also identified in populations from Angola and Cape Verde, extending our knowledge about the distribution of these mutations in Africa. We found significant associations between kdr genotypes and the resistance phenotype but only in the Angolan population. These results suggest that populations carrying the same kdr mutations may respond differently to the same insecticide, stressing the need for complementary studies when assessing the impact of kdr resistance in the outcome of insecticide-based vector control.

Background Aedes aegypti is a major mosquito vector of arboviruses, including dengue, chikungunya and Zika. In 2005, Ae. aegypti was identified for the first time in Madeira Island. Despite an initial insecticide-based vector control program, the species expanded throughout the Southern coast of the island, suggesting the presence of insecticide resistance. Here, we characterized the insecticide resistance status and the underlying mechanisms of two populations of Ae. aegypti from Madeira Island, Funchal and Paúl do Mar. Methodology/Principal findings WHO susceptibility bioassays indicated resistance to cyfluthrin, permethrin, fenitrothion and bendiocarb. Use of synergists significantly increased mortality rates, and biochemical assays indicated elevated activities of detoxification enzymes, suggesting the importance of metabolic resistance. Microarray-based transcriptome analysis detected significant upregulation in both populations of nine cytochrome P450 oxidase genes (including four known pyrethroid metabolizing enzymes), the organophosphate metabolizer CCEae3a, Glutathione-S-transferases, and multiple putative cuticle proteins. Genotyping of knockdown resistance loci linked to pyrethroid resistance revealed fixation of the 1534C mutation, and presence with moderate frequencies of the V1016I mutation in each population. Conclusions/Significance Significant resistance to three major insecticide classes (pyrethroid, carbamate and organophosphate) is present in Ae. aegypti from Madeira Island, and appears to be mediated by multiple mechanisms. Implementation of appropriate resistance management strategies including rotation of insecticides with alternative modes of action, and methods other than chemical-based vector control are strongly advised to delay or reverse the spread of resistance and achieve efficient control., Author summary Aedes aegypti is the major mosquito vector of dengue, chikungunya and Zika worldwide. After its introduction in Madeira, it took a few years for the first dengue outbreak to occur in the region. Control strategies rely mostly on the use of insecticides but their efficiency is often being hampered by the ability of mosquitoes to resist to the compounds used. In fact, previous vector control programs using insecticides failed to eradicate, or even, to limit the spread of Ae. aegypti in Funchal, and now, the mosquito is widely distributed throughout the southern coast of the island. Bioassays to determine insecticide susceptibility profiles were carried-out in two populations of Madeira Island and the molecular mechanisms underlying the observed insecticide resistance phenotype were investigated. Transcription levels of detoxification genes were analysed, and screenings for kdr mutations, V1016I and F1534C, associated with pyrethroid resistance were performed. Our study showed the up-regulation of several detoxification genes of multiple enzyme families associated with metabolic resistance, and the presence of the two kdr mutations, with the F1534C being fixed. Another suggested mechanism probably involved in the resistance phenotype is cuticle thickening, as several cuticle genes were found overexpressed. This study reinforces the importance of alternative control strategies to suppress Ae. aegypti population and thus reduce the likelihood of arbovirus transmission in the region.

Background Since its emergence in 2007 in Micronesia and Polynesia, the arthropod-borne flavivirus Zika virus (ZIKV) has spread in the Americas and the Caribbean, following first detection in Brazil in May 2015. The risk of ZIKV emergence in Europe increases as imported cases are repeatedly reported. Together with chikungunya virus (CHIKV) and dengue virus (DENV), ZIKV is transmitted by Aedes mosquitoes. Any countries where these mosquitoes are present could be potential sites for future ZIKV outbreak. We assessed the vector competence of European Aedes mosquitoes (Aedes aegypti and Aedes albopictus) for the currently circulating Asian genotype of ZIKV. Methodology/Principal Findings Two populations of Ae. aegypti from the island of Madeira (Funchal and Paul do Mar) and two populations of Ae. albopictus from France (Nice and Bar-sur-Loup) were challenged with an Asian genotype of ZIKV isolated from a patient in April 2014 in New Caledonia. Fully engorged mosquitoes were then maintained in insectary conditions (28°±1°C, 16h:8h light:dark cycle and 80% humidity). 16–24 mosquitoes from each population were examined at 3, 6, 9 and 14 days post-infection to estimate the infection rate, disseminated infection rate and transmission efficiency. Based on these experimental infections, we demonstrated that Ae. albopictus from France were not very susceptible to ZIKV. Conclusions/Significance In combination with the restricted distribution of European Ae. albopictus, our results on vector competence corroborate the low risk for ZIKV to expand into most parts of Europe with the possible exception of the warmest regions bordering the Mediterranean coastline., Author Summary In May 2015, local transmission of Zika virus (ZIKV) was reported in Brazil and since then, more than 1.5 million human cases have been reported in Latin America and the Caribbean. This arbovirus, primarily found in Africa and Asia, is mainly transmitted by Aedes mosquitoes, Aedes aegypti and Aedes albopictus. Viremic travelers returning from America to European countries where Ae. albopictus is established could become the source for local transmission of ZIKV. In order to estimate the risk of seeding ZIKV into local mosquito populations, the susceptibility of European Ae. aegypti and Ae. albopictus to ZIKV was measured using experimental infections. We demonstrated that Ae. albopictus and Ae. aegypti from Europe were not very susceptible to ZIKV. The threat for a Zika outbreak in Europe should be limited.

Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti from 30 countries in six continents, and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co-occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya), the two subspecies remain genetically distinct, whereas in urban settings, they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats and low migration rates. Ancestral populations in sub-Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans-Atlantic shipping in the 16th to 18th centuries was followed by its introduction to Asia in the late 19th century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for the methods using genetic modification of populations., Centro de Estudios Parasitológicos y de Vectores

Ecology, development, behaviour, and survival of mosquitoes as well as the transmission dynamic of pathogens, strongly depend on climatic factors. Models have been developed to predict forthcoming mosquito-borne diseases scenarios based on estimations of future climate patterns. However, the complex interplay of climate variables with the mosquito-host-pathogen systems rend the overall effect of the climate on the local prevalence of mosquito-borne diseases difficult to determine. Therefore, the assumption that warmer global temperatures will produce increase mosquito proliferation and geographic range may not be entirely true. Furthermore, general climatic observations may not reflect the local microclimates experienced by mosquitoes, mainly by the synantrophic species which live in mild human-modified habitats. Human socio-economic context, community’s culture or behavioural habits are also sidestepped factors prone to influence MBD transmission.

Background The malaria vector Anopheles arabiensis exhibits greater behavioural and ecological plasticity than the other major vectors of the Anopheles gambiae complex, which presents challenges for major control methods. This study reports for the first time the presence of An. arabiensis in Antula, a suburb of Bissau city, the capital of Guinea Bissau, where high levels of hybridization between Anopheles coluzzii and An. gambiae have been reported. Given that previous surveys in the area, based on indoor collections, did not sample An. arabiensis, the possibility of a recently introduced exophilic population was investigated. Methods Larval and adult mosquito collections were carried out in Antula at the end of the rainy season of 2010. Anopheles gambiae species composition, determined by rDNA-IGS and SINE200X6.1 markers, was compared with four previously collected samples dating back to 1993. Analysis of ten microsatellites was used to estimate levels of genetic diversity, relatedness and to investigate demographic stability. Results Anopheles arabiensis comprised 54.0% of larvae and 25.6% of adults collected in 2010, but was absent in all previous collections, a highly unlikely observation by chance if the population was stable. This species had the lowest levels of genetic diversity, highest relatedness and, along with An. gambiae, exhibited evidence of a recent population expansion. Conclusions Results point to the presence of a previously undetected outdoor population of An. arabiensis in Antula, which appears to have expanded recently, highlighting the importance of complementing indoor-based mosquito collections with sampling methods targeting outdoor adults and immature stages for a more complete assessment of mosquito biodiversity. A change in temporal dynamics in the species complex composition was also detected. Coupled with previous evidence of asymmetric introgression from An. coluzzii to An. gambiae, this suggests that the study area may be subject to ecological changes with a potential impact on both the genetics of these species and on malaria transmission. Electronic supplementary material The online version of this article (doi:10.1186/1475-2875-13-423) contains supplementary material, which is available to authorized users.

Made available in DSpace on 2014-09-30T18:18:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2013Bitstream added on 2014-10-01T14:04:14Z : No. of bitstreams: 1 S0074-02762013000900003.pdf: 529161 bytes, checksum: 81385c72bbd25c5d11a271d286f7317a (MD5) The increasing population of Aedes aegypti mosquitoes on Madeira Island (Portugal) resulted in the first autochthonous dengue outbreak, which occurred in October 2012. Our study establishes the first genetic evaluation based on the mitochondrial DNA (mtDNA) genes [cytochrome oxidase subunit I (COI) and NADH dehydrogenase subunit 4 (ND4)] and knockdown resistance ( kdr ) mutations exploring the colonisation history and the genetic diversity of this insular vector population. We included mosquito populations from Brazil and Venezuela in the analysis as putative geographic sources. The Ae. aegyptipopulation from Madeira showed extremely low mtDNA genetic variability, with a single haplotype for COI and ND4. We also detected the presence of two important kdr mutations and the quasi-fixation of one of these mutations (F1534C). These results are consistent with a unique recent founder event that occurred on the island of Ae. aegyptimosquitoes that carry kdr mutations associated with insecticide resistance. Finally, we also report the presence of the F1534C kdr mutation in the Brazil and Venezuela populations. To our knowledge, this is the first time this mutation has been found in South American Ae. aegypti mosquitoes. Given the present risk of Ae. aegypti re-invading continental Europe from Madeira and the recent dengue outbreaks on the island, this information is important to plan surveillance and control measures. Unidade de Ensino e Investigacao-Parasitologia Medica Centro de Malaria e outras Doencas Tropicais Universidade Nova de Lisboa Instituto de Higiene e Medicina Tropical Unidade de Parasitologia e Microbiologia Medicas Instituto de Administracao da Saude e Assuntos Sociais Unidade de Engenharia Sanitaria Departamento de Promocao e Protecao da Saude Universidade Estadual Paulista Instituto de Biociencias Departamento de Parasitologia Universidad Central de Venezuela Instituto de Medicina Tropical Seccion Entomologia Medica Universidade Estadual Paulista Instituto de Biociencias Departamento de Parasitologia

Background Community participation is mandatory in the prevention of Dengue outbreaks. Taking public views into account is crucial to guide more effective planning and quicker community participation in preventing campaigns. This study aims to assess community perceptions of Madeira population in order to explore their involvement in the A. aegypti’s control and reinforce health-educational planning. Due to the lack of accurate methodologies for measuring perception, a new tool to assess the community’s perceptions was built. Methods A cross-sectional survey was performed in the Island’s aegypti-infested area, exploring residents’ perceptions regarding most critical community behaviour: aegypti-source reduction and their domestic aegypti-breeding sites. A novel tool defining five essential topics which underlie the source reduction’s awareness and accession was built, herein called Essential-Perception (EP) analysis. Results Of 1276 individuals, 1182 completed the questionnaire (92 · 6%). EP-Score analysis revealed that community’s perceptions were scarce, inconsistent and possibly incorrect. Most of the population (99 · 6%) did not completely understood the five essential topics explored. An average of 54 · 2% of residents only partially understood each essential topic, revealing inconsistencies in their understanding. Each resident apparently believed in an average of four false assumptions/myths. Significant association (pAedes aegypti’s breeding sites, consisting of décor/leisure containers, presented an atypical pattern of infestation comparing with dengue prone regions. Conclusions The studied population was not prepared for being fully engaged in dengue prevention. Evidences suggest that EP-methodology was efficient and accurate in assessing the community perception and its compliance to practices. Moreover, it suggested a list of myths that could persist in the community. This is the first study reporting an aegypti-entomological pattern and community’s perception in a developed dengue-prone region. Tailored messages considering findings of this study are recommended to be used in future campaigns in order to more effectively impact the community perception and behaviour.

Background In 2012, the first dengue virus outbreak was reported on the Portuguese island of Madeira with 1080 confirmed cases. Dengue virus of serotype 1 (DENV-1), probably imported from Venezuela, caused this outbreak with autochthonous transmission by invasive Aedes aegypti mosquitoes. Results We investigated the seroprevalence among the population on Madeira Island four years after the outbreak. Study participants (n = 358), representative of the island population regarding their age and gender, were enrolled in 2012 in a cross-sectional study. Dengue antibodies were detected with an in-house enzyme-linked immunosorbent assay (ELISA) using the dimer of domain III (ED3) of the DENV-1 envelope protein as well as commercial Panbio indirect and capture IgG ELISAs. Positive ELISA results were validated with a neutralization test. The overall seroprevalence was found to be 7.8% (28/358) with the in-house ELISA, whereas the commercial DENV indirect ELISA detected IgG antibodies in 8.9% of the individuals (32/358). The results of the foci reduction neutralization test confirmed DENV-1 imported from South America as the causative agent of the 2012 epidemic. Additionally, we found a higher seroprevalence in study participants with an age above 60 years old and probable secondary DENV infected individuals indicating unreported dengue circulation before or after 2012 on Madeira Island. Conclusions This study revealed that the number of infections might have been much higher than estimated from only confirmed cases in 2012/2013. These mainly DENV-1 immune individuals are not protected from a secondary DENV infection and the majority of the population of Madeira Island is still naïve for DENV. Surveillance of mosquitoes and arboviruses should be continued on Madeira Island as well as in other European areas where invasive vector mosquitoes are present. Electronic supplementary material The online version of this article (10.1186/s13071-019-3357-3) contains supplementary material, which is available to authorized users.

Following the identification of two autochthonous cases of dengue type 1 on 3 October 2012, an outbreak of dengue fever has been reported in Madeira, Portugal. As of 25 November, 1,891 cases have been detected on the island where the vector Aedes aegypti had been established in some areas since 2005. This event represents the first epidemic of dengue fever in Europe since 1928 and concerted control measures have been initiated by local health authorities.

International audience; Both Aedes aegytpi and Ae. albopictus are major vectors of 5 important arboviruses (namely chikungunya virus, dengue virus, Rift Valley fever virus, yellow fever virus, and Zika virus), making these mosquitoes an important factor in the worldwide burden of infectious disease. Vector control using insecticides coupled with larval source reduction is critical to control the transmission of these viruses to humans but is threatened by the emergence of insecticide resistance. Here, we review the available evidence for the geographical distribution of insecticide resistance in these 2 major vectors worldwide and map the data collated for the 4 main classes of neurotoxic insecticide (carbamates, organochlorines, organophosphates, and pyrethroids). Emerging resistance to all 4 of these insecticide classes has been detected in the Americas, Africa, and Asia. Target-site mutations and increased insecticide detoxification have both been linked to resistance in Ae. aegypti and Ae. albopictus but more work is required to further elucidate metabolic mechanisms and develop robust diagnostic assays. Geographical distributions are provided for the mechanisms that have been shown to be important to date. Estimating insecticide resistance in unsampled locations is hampered by a lack of standardisation in the diagnostic tools used and by a lack of data in a number of regions for both resistance phenotypes and genotypes. The need for increased sampling using standard methods is critical to tackle the issue of emerging insecticide resistance threatening human health. Specifically, diagnostic doses and well-characterised susceptible strains are needed for the full range of insecticides used to control Ae. aegypti and Ae. albopictus to standardise measurement of the resistant phenotype, and calibrated diagnostic assays are needed for the major mechanisms of resistance.