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We searched for evidence of knockdown resistance (kdr) mutations in the voltage-gated sodium channel gene of Aedes aegypti (Linnaeus) (Diptera: Culicidae) and Aedes albopictus (Skuse) (Diptera: Culicidae) mosquitoes from Panama. Conventional PCR was performed on 469 Ae. aegypti and 349 Ae. albopictus. We did not discover kdr mutations in Ae. albopictus, but 2 nonsynonymous kdr mutations, V1016I (found in 101 mosquitoes) and F1534C (found in 29 of the mosquitoes with the V1016I), were detected in Ae. aegypti. These kdr mutations were present in all specimens that were successfully sequenced for both IIS5-S6 and IIIS6 regions, which included samples collected from 8 of the 10 provinces of Panama. No other kdr mutations were found in Ae. aegypti, including V1016G, which has already been reported in Panama. Findings suggest that the V1016I-F1534C variant is prevalent in Panama, which might be related to the introduction and passive movement of mosquitoes as part of the used-tire trade. However, we cannot rule out the possibility that selection on de novo replacement of kdr mutations also partially explains the widespread distribution pattern of these mutations. These 2 ecological and evolutionary processes are not mutually exclusive, though, as they can occur in tandem. Research in Panama needs to calculate the genotypic and allelic frequencies of kdr alleles in local Ae. aegypti populations and to test whether some combinations confer phenotypic resistance or not. Finally, future studies will have to track the introduction and spreading of new kdr mutations in both Aedes species.

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Aedes aegypti and Aedes albopictus are responsible for transmitting major human arboviruses such as Dengue, Zika, and Chikungunya, posing a global threat to public health. The lack of etiological treatments and efficient vaccines makes vector control strategies essential for reducing vector population density and interrupting the pathogen transmission cycle. This study evaluated the impact of long-term pyriproxyfen exposure on the genetic structure and diversity of Ae. aegypti and Ae. albopictus mosquito populations. The study was conducted in Manaus, Amazonas, Brazil, where pyriproxyfen dissemination stations have been monitored since 2014 up to the present day. Double digest restriction-site associated DNA sequencing was performed, revealing that despite significant local population reductions by dissemination stations with pyriproxyfen in various locations in Brazil, focal intervention has no significant impact on the population stratification of these vectors in urban scenarios. The genetic structuring level of Ae. aegypti suggests it is more stratified and directly affected by pyriproxyfen intervention, while for Ae. albopictus exhibits a more homogeneous and less structured population. The results suggest that although slight differences are observed among mosquito subpopulations, intervention focused on neighborhoods in a capital city is not efficient in terms of genetic structuring, indicating that larger-scale pyriproxyfen interventions should be considered for more effective urban mosquito control.

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The Asian tiger mosquito, Aedes albopictus, is a highly invasive and aggressive species capable of transmitting a large number of etiological agents of medical and veterinary importance, posing a high risk for the transmission of emerging viruses between animals and humans. In this work, we evaluated the mosquitocidal activity of Neochloris aquatica against A. albopictus throughout its development and analyzed whether this effect was potentiated when the microalga was cultivated under stress conditions due to nutrient deprivation. Our results suggest that N. aquatica produces metabolites that have negative effects on these insects, including larval mortality, interruption of pupal development, and incomplete emergence of adults when fed on microalgae in the larval stages. When microalgae were cultured under stress conditions, an increase in molting defects was recorded, and the number of healthy adults emerged drastically decreased. Histological studies revealed severe signs of total disintegration of different tissues and organs in the thorax and abdomen regions. The muscles and fat bodies in the midgut and foregut were severely distorted. In particular, larval intestinal tissue damage included vacuolization of the cytoplasm, destruction of brush border microvilli, and dilation of the intercellular space, which are distinctive morphological characteristics of apoptotic cells. Evidence suggests that N. aquatica produces metabolites with mosquitocidal effects that affect development and, therefore, the ability to vector etiological agents of medical and veterinary importance.

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BACKGROUND The presence of Aedes albopictus in Bolivia has been a subject of controversy, with a lack of concrete documentation. OBJECTIVES This study aimed to provide evidence of Ae. albopictus presence in Bolivia. METHODS Larval habitats were sampled in Rosario del Yata and San Agustín, Guayaramerín Municipality, Beni Department, northern Bolivia. Collected mosquito larvae were reared to the L4 and adult stages for morphological identification, with some specimens sequenced for confirmation. FINDINGS Aedes albopictus was identified in multiple larval habitats within peridomestic areas, such as buckets, canisters, and cut plastic bottles used as flower vases in both localities, confirming its establishment in the area. This represents the first concrete documentation of the species in Bolivia. The collections (larvae and adults) have been deposited in the Medical Entomology Laboratory of the Universidad Mayor de San Simón in Cochabamba, Bolivia, and the Laboratory of Entomology of the Instituto Nacional de Laboratorios de Salud of the Ministry of Health in La Paz, Bolivia. MAIN CONCLUSION Given its role as a vector for arboviruses such as dengue and Chikungunya, Ae. albopictus should be incorporated into the Bolivian National Programme of Vector Control for monitoring.

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Dengue continues to be a major public health concern in Latin America and the Caribbean with many countries in the region having experienced drastic increases in the incidence of dengue over the past few years. Dengue virus is predominantly transmitted by the bite of an infected female Aedes aegypti mosquito via a process called horizontal transmission. However, the virus may also be transmitted from an infected female mosquito to her offspring by vertical transmission, which occurs via viral invasion of the ovary either at the time of fertilization or during oviposition. In this way, mosquitoes may become dengue virus infected before ever encountering a human host. While some researchers have reported this phenomenon and suggested it may serve as a reservoir for the dengue virus in nature, others have questioned its epidemiological significance because of the low frequency at which it has been observed. Several researchers have either altogether failed to detect it or observed its occurrence at low frequencies. However, some studies have attributed these failures to small sample sizes as well as poor sensitivities of screening methods employed. Therefore, an overview of the occurrence, significance and limitations of detection of vertical transmission of dengue virus in Aedes mosquitoes in nature within Latin America and the Caribbean will be the focus of this review.

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The largest outbreak of sylvatic yellow fever virus (YFV) in eight decades was recorded in Brazil between 2016-2018. Besides human and NHP surveillance, the entomo-virological approach is considered as a complementary tool. For this study, a total of 2904 mosquitoes of the Aedes, Haemagogus and Sabethes genera were collected from six Brazilian states (Bahia, Goiás, Mato Grosso, Minas Gerais, Pará, and Tocantins) and grouped into 246 pools, which were tested for YFV using RT-qPCR. We detected 20 positive pools from Minas Gerais, 5 from Goiás, and 1 from Bahia, including 12 of Hg. janthinomys and 5 of Ae. albopictus. This is the first description of natural YFV infection in this species and warns of the likelihood of urban YFV re-emergence with Ae. albopictus as a potential bridge vector. Three YFV sequences from Hg. janthinomys from Goiás and one from Minas Gerais, as well as one from Ae. albopictus from Minas Gerais were clustered within the 2016-2018 outbreak clade, indicating YFV spread from Midwest and its infection in a main and likely novel bridging vector species. Entomo-virological surveillance is critical for YFV monitoring in Brazil, which could highlight the need to strengthen YFV surveillance, vaccination coverage, and vector control measures.

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The risk of the emergence and reemergence of zoonoses is high in regions that are under the strong influence of anthropogenic actions, as they contribute to the risk of vector disease transmission. Yellow fever (YF) is among the main pathogenic arboviral diseases in the world, and the Culicidae Aedes albopictus has been proposed as having the potential to transmit the yellow fever virus (YFV). This mosquito inhabits both urban and wild environments, and under experimental conditions, it has been shown to be susceptible to infection by YFV. In this study, the vector competence of the mosquito Ae. albopictus for the YFV was investigated. Female Ae. albopictus were exposed to non-human primates (NHP) of the genus Callithrix infected with YFV via a needle inoculation. Subsequently, on the 14th and 21st days post-infection, the legs, heads, thorax/abdomen and saliva of the arthropods were collected and analyzed by viral isolation and molecular analysis techniques to verify the infection, dissemination and transmission. The presence of YFV was detected in the saliva samples through viral isolation and in the head, thorax/abdomen and legs both by viral isolation and by molecular detection. The susceptibility of Ae. albopictus to YFV confers a potential risk of reemergence of urban YF in Brazil.

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Aedes albopictus (Skuse, 1894) is one of the major vectors for arboviruses such as dengue, Zika, and chikungunya. Originally from Southeast Asia, this species has spread to Africa, Europe, and the Americas, including Cuba. This spread has been favored by its great adaptability to variable temperatures and to the resistance of its eggs to desiccation. Chemical control of mosquitoes is an essential alternative to stop arbovirus transmission, but insecticide resistance status of the Cuban Ae. albopictus populations is unknown. For this study, Ae. albopictus larvae and adults were collected from two municipalities in Havana, Cuba in 2019. Adult bioassays for deltamethrin, cypermethrin, lambda-cyhalothrin, chlorpyrifos, propoxur, and bendiocarb susceptibility were conducted according to CDC methodology. Larval bioassays for temephos susceptibility were performed following WHO protocols. Resistance profiles for α and ß-esterases, glutathione S-transferase (GST), and multifunction oxidases (MFO) pathways were constructed and analyzed. Resistance to temephos and deltamethrin was detected in Mulgoba and Plaza field populations, but resistance to lambda-cyhalothrin was only found in the Plaza colony. Plaza colony exhibited a higher expression level to all four metabolic enzymes and α-esterases and GTS were over-expressed in Mulgoba. The development of insecticide resistance in Cuban Ae. albopictus populations makes it imperative that we develop integrated control strategies to minimize the development of resistance and provide effective vector control that prevents the onset of arbovirus epidemics.

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Various arboviruses are transmitted to humans by mosquitoes, particularly Aedes aegypti and Aedes albopictus, two invasive and frequently sympatric species. The objective of this study was to evaluate the dispersion and the behavior of Ae. albopictus in relation to houses and its association with other mosquitoes in the province of Havana, Cuba. All water-containing deposits in the houses or vacant lots in urban and peri­urban municipalities of the province of Havana were sampled during the two study periods: 1995-1999 and 2010-2018. The following patterns in the presence of Ae. albopictus in the study area were observed: a persistent absence of Ae. albopictus in one of the municipalities; a rapid dispersion in the second period, staring from the absence of vector in the first period, in tow other municipalities; and a sustained decrease in the dispersion of Ae.albopictus in two other municipalities. The peripheral municipalities noted the highest presence of Ae. albopictus, but few associations with other mosquitoes. However, overall, we found an increase in this association when comparing the period 2010-2018 with the first period. Ae. albopictus was present in 8% (2016) to 21.5% (2013) inside the houses with an average of 15%, which evidences an initial domiciliation of the species. The results obtained in this work show an initiation of domiciliation of Ae. albopictus in the urban area of the province of Havana. This is important to alert the National Control Program to strengthen the entomological monitoring of Ae. albopictus, and not only Ae. aegypti. The follow-up of this domiciliation is important to guide control efforts, knowing its role as a vector of different arboviruses.

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Earth observation environmental features measured through remote sensing and models of vector mosquitoes species Aedes aegypti and Ae. albopictus provide an advancement with regards to dengue risk in urban environments of subtropical areas of Argentina. The authors aim to estimate the effect of landscape coverage and spectral indices (Normalized Difference Vegetation Index [NDVI], Normalized Difference Water Index [NDWI] and Normalized Difference Built-up Index [NDBI]) on the larvae abundance of Ae. aegypti and Ae. albopictus in Eldorado, Misiones, Argentina using remote satellite sensors. Larvae of these species were collected monthly (June 2016 to April 2018), in four environments: tire repair shops, cemeteries, dwellings and an urban natural park. The proportion of landscape coverage (water, urban areas, bare soil, low vegetation and high vegetation) was determined from the supervised classification of Sentinel-2 images and spectral indices, calculated. The authors developed spatial models of both vector species by generalized linear mixed models. The model's results showed that Ae. aegypti larvae abundance was better modelled by NDVI minimum values, NDBI maximum values and the interaction between them. For Ae. albopictus proportion of bare soil, low vegetation and the interaction between both variables explained better the abundance.

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Arboviral infections transmitted by Aedes spp. mosquitoes are a major threat to human health, particularly in tropical regions but are expanding to temperate regions. The ability of Aedes aegypti and Aedes albopictus to transmit multiple arboviruses involves a complex relationship between mosquitoes and the virus, with recent discoveries shedding light on it. Furthermore, this relationship is not solely between mosquitoes and arboviruses, but also involves the mosquito microbiome. Here, we aimed to construct a comprehensive review of the latest information about the arbovirus infection process in A. aegypti and A. albopictus, the source of mosquito microbiota, and its interaction with the arbovirus infection process, in terms of its implications for vectorial competence. First, we summarized studies showing a new mechanism for arbovirus infection at the cellular level, recently described innate immunological pathways, and the mechanism of adaptive response in mosquitoes. Second, we addressed the general sources of the Aedes mosquito microbiota (bacteria, fungi, and viruses) during their life cycle, and the geographical reports of the most common microbiota in adults mosquitoes. How the microbiota interacts directly or indirectly with arbovirus transmission, thereby modifying vectorial competence. We highlight the complexity of this tripartite relationship, influenced by intrinsic and extrinsic conditions at different geographical scales, with many gaps to fill and promising directions for developing strategies to control arbovirus transmission and to gain a better understanding of vectorial competence. The interactions between mosquitoes, arboviruses and their associated microbiota are yet to be investigated in depth.

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ABSTRACT Aedes (Stegomyia) albopictus (Skuse, 1854) was reported in Brazil for the first time in 1986 and has shown marked expansion throughout the Brazilian territory. During a routine activity to control dengue fever conducted by the Division of Entomology of the Municipal Health Department in Rio Branco city, adults and immatures of Culicidae were collected in a peri-urban area. The identified Culicidae forms indicated that they belonged to the species Ae. albopictus. This is the first official record of the presence of Ae. albopictus in the Acre State, confirming its current presence in all Brazilian states.

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Insect-specific viruses (ISVs) are viruses that replicate exclusively in arthropod cells. Many ISVs have been studied in mosquitoes as many of them act as vectors for human etiological agents, such as arboviruses. Aedes (Stegomyia) albopictus is an important potential vector of several arboviruses in Brazil, such as dengue (DENV), Zika (ZIKV) and chikungunya (CHIKV). The development of next-generation sequencing metagenomics has enabled the discovery and characterization of new ISVs. Ae. albopictus eggs were collected using oviposition traps placed in two urban parks in the city of São Paulo, Brazil. The Aedes albopictus females were divided into pools and the genetic material was extracted and processed for sequencing by metagenomics. Complete genomes of ISV Wenzhou sobemo-like virus 4 (WSLV4) were obtained in three of the four pools tested. This is the first detection of ISV WSLV4 in Ae. albopictus females in Latin America. Further studies on ISVs in Ae. albopictus are needed to better understand the role of this species in the dynamics of arbovirus transmission in the Americas.

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Aedes aegypti and Aedes albopictus are considered the most important vectors of arboviruses in the world. Aedes aegypti is the primary vector of dengue, urban yellow fever, chikungunya and zika in Brazil, and Ae. albopictus is considered a potential vector. Distribution patterns and the influence of climatic variables on the oviposition of Ae. aegypti and Ae. albopictus were evaluated in Morretes, a tourist city in the coastal area of Paraná State, Brazil, which has recently been experiencing cases of dengue fever. Eggs were collected using ovitraps over a period of one year (September 2017 to September 2018) and reared from hatching until the emergence of the adults. Both Aedes species were found in anthropized areas with a high human density index. Findings suggest that the monthly average temperature (LRT = 16.65, p = 0.001) had significant positive influences on the oviposition of the Aedes species. Considering the wide distribution of DENV around the Paraná coast and the presence of Ae. albopictus alongside Ae. aegypti, studies on natural arbovirus infection patterns and seasonality are recommended in the region.

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BACKGROUND: The rapid worldwide spreading of Aedes aegypti and Aedes albopictus is expanding the risk of arboviral diseases transmission, pointing out the urgent need to improve monitoring and control of mosquito vector populations. Assessment of human-vector contact, currently estimated by classical entomological methods, is crucial to guide planning and implementation of control measures and evaluate transmission risk. Antibody responses to mosquito genus-specific salivary proteins are emerging as a convenient complementary tool for assessing host exposure to vectors. We previously showed that IgG responses to the Ae. albopictus 34k2 salivary protein (al34k2) allow detection of seasonal and geographic variation of human exposure to the tiger mosquito in two temperate areas of Northeast Italy. The main aim of this study was to confirm and extend these promising findings to tropical areas with ongoing arboviral transmission. METHODS: IgG responses to al34k2 and to the Ae. aegypti orthologous protein ae34k2 were measured by ELISA in cohorts of subjects only exposed to Ae. albopictus (Réunion Island), only exposed to Ae. aegypti (Bolivia) or unexposed to both these vectors (North of France). RESULTS AND CONCLUSION: Anti-al34k2 IgG levels were significantly higher in sera of individuals from Réunion Island than in unexposed controls, indicating that al34k2 may be a convenient and reliable proxy for whole saliva or salivary gland extracts as an indicator of human exposure to Ae. albopictus. Bolivian subjects, exposed to bites of Ae. aegypti, carried in their sera IgG recognizing the Ae. albopictus al34k2 protein, suggesting that this salivary antigen can also detect, even though with low sensitivity, human exposure to Ae. aegypti. On the contrary, due to the high background observed in unexposed controls, the recombinant ae34k2 appeared not suitable for the evaluation of human exposure to Aedes mosquitoes. Overall, this study confirmed the suitability of anti-al34k2 IgG responses as a specific biomarker of human exposure to Ae. albopictus and, to a certain extent, to Ae. aegypti. Immunoassays based on al34k2 are expected to be especially effective in areas where Ae. albopictus is the main arboviral vector but may also be useful in areas where Ae. albopictus and Ae. aegypti coexist.

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Aedes albopictus, also known as the tiger mosquito, is widespread worldwide across tropical, subtropical, and temperate regions. This insect is associated with the transmission of several vector-borne diseases, and, as such, monitoring its distribution is highly important for public health. In Ecuador, Ae. albopictus was first reported in 2017 in Guayaquil. Since then, the vector has been identified in the Northeastern lowlands and the Amazon basin. This study aims to determine the genetic diversity of Ecuadorian populations of Ae. albopictus through the analysis of the mitochondrial gene COI and to describe the potential distribution areas of this species within the country. The genetic diversity was determined by combining phylogenetic and population genetics analyses of five localities in Ecuador. Results showed two haplotypes in the Ecuadorian populations of Ae. albopictus. Haplotype 1 (H1) was found in the coastal and Amazon individuals, while haplotype 2 (H2) was only found in the three northeastern lowlands sites. In a worldwide context, H1 is the most widespread in 21 countries with temperate and tropical habitats. In contrast, H2 distribution is limited to five countries in tropical regions, suggesting fewer adaptation traits. Our prediction model showed a suitable habitat for Ae. albopictus in all regions (coastal, Amazon basin, and Andean lowland regions and the Galápagos Islands) of Ecuador. Hence, understanding different aspects of the vector can help us implement better control strategies for surveillance and vectorial control in Ecuador.

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Resumen INTRODUCCION: El dengue es causado por un virus perteneciente a la familia Flaviviridae; existen cuatro serotipos relacionados: DENV-1, DENV-2, DENV-3, DENV-4 trasmitidos por picadura del mosquito hembra de las especies Aedes aegypti y Aedes albopictus. CASO CLÍNICO: Paciente de 19 años, con 36 semanas de embarazo por fecha de la última menstruación y diagnóstico de dengue por serología positiva (Ag-NS1) y trombocitopenia (68,000/mm3). El padecimiento se inició con fiebre de 38.0°C, de tres días de evolución acompañado de artralgias, mialgias, dolor retro ocular y contracciones uterinas. La paciente se ingresó al área de terapia intensiva debido a insuficiencia respiratoria (que ameritó ventilación mecánica invasiva), insuficiencia renal aguda y hematológica, posterior a cesárea. Ameritó reintervención quirúrgica por sangrado intrabdominal por trastornos de la coagulación. Durante su estancia hospitalaria requirió 50 concentrados plaquetarios, 8 concentrados eritrocitarios, 14 plasmas frescos y 4 aféresis plaquetarias. Después de 14 días de estancia hospitalaria se dio de alta por mejoría clínica. CONCLUSIÓN: Si no se actúa inmediatamente, el dengue grave es una causa de desenlace fatal madre-hijo. La identificación oportuna de las complicaciones agregadas a esta enfermedad en la embarazada denota la importancia de la prevención, el diagnóstico temprano y su tratamiento. De igual manera, es importante que en pacientes embarazadas con esta comorbilidad el servicio de Obstetricia intervenga oportunamente en la vigilancia pre y posquirúrgica.

Abstract BACKGROUND: Dengue is caused by a virus belonging to the Flaviviridae family, there are four related serotypes: DENV-1, DENV-2, DENV-3, DENV-4 transmitted by the bite of the female mosquito of the species Aedes aegypti and Aedes albopictus. CLINICAL CASE: 19-year-old female patient, 36 weeks pregnant by date of last menstrual period and diagnosed with dengue due to positive serology (Ag-NS1) and thrombocytopenia (68,000/mm3). The illness started with fever of 38.0°C, of three days of evolution accompanied by arthralgias, myalgias, retro ocular pain and uterine contractions. The patient was admitted to the intensive care unit due to respiratory failure (which required invasive mechanical ventilation), acute renal and hematologic failure, following cesarean section. She required surgical reintervention for intra-abdominal bleeding due to coagulation disorders. During her hospital stay she required 50 platelet concentrates, 8 erythrocyte concentrates, 14 fresh plasmas and 4 platelet apheresis. After 14 days of hospital stay he was discharged due to clinical improvement. CONCLUSION: If no immediate action is taken, severe dengue is a cause of fatal mother-child outcome. The timely identification of the complications associated with this disease in pregnant women highlights the importance of prevention, early diagnosis and treatment. Similarly, it is important that in pregnant patients with this comorbidity, the obstetrics service should intervene in a timely manner in pre- and post-surgical surveillance.

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BACKGROUND: Aedes aegypti and Ae. albopictus are vectors of numerous arboviruses that adversely affect human health. In mosquito vectors of disease, the bacterial microbiota influence several physiological processes, including fertility and vector competence, making manipulation of the bacterial community a promising method to control mosquito vectors. In this study, we describe the reproductive tract tissue microbiota of lab-reared virgin Ae. aegypti and Ae. albopictus males, and virgin, mated, and mated + blood-fed females of each species, comparing the bacterial composition found there to the well-described gut microbiota. METHODS: We performed metabarcoding of the 16S rRNA isolated from the gut, upper reproductive tract (URT; testes or ovaries), and lower reproductive tract (LRT; males: seminal vesicles and accessory glands; females: oviduct, spermathecae, and bursa) for each species, and evaluated the influence of host species, tissue, nutritional status, and reproductive status on microbiota composition. Finally, based on the identified taxonomic profiles of the tissues assessed, bacterial metabolic pathway abundance was predicted. RESULTS: The community structure of the reproductive tract is unique compared to the gut. Asaia is the most prevalent OTU in the LRTs of both Ae. aegypti and Ae. albopictus. In the URT, we observed differences between species, with Wolbachia OTUs being dominant in the Ae. albopictus URT, while Enterobacter and Serratia were dominant in Ae. aegypti URT. Host species and tissue were the best predictors of the community composition compared to reproductive status (i.e., virgin or mated) and nutritional status (i.e., sugar or blood-fed). The predicted functional profile shows changes in the abundance of specific microbial pathways that are associated with mating and blood-feeding, like energy production in mated tissues and siderophore synthesis in blood-fed female tissues. CONCLUSIONS: Aedes aegypti and Ae. albopictus have distinct differences in the composition of microbiota found in the reproductive tract. The distribution of the bacterial taxonomic groups indicates that some bacteria have tissue-specific tropism for reproductive tract tissue, such as Asaia and Wolbachia. No significant differences in the taxonomic composition were observed in the reproductive tract between virgin, mated, and mated + blood-fed females, but changes in the abundance of specific metabolic pathways were found in the predicted microbial functional profiles in mated and blood-fed females.

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BACKGROUND: Dengue, Zika and chikungunya are arboviruses of significant public health importance that are transmitted by Aedes aegypti and Aedes albopictus mosquitoes. In Colombia, where dengue is hyperendemic, and where chikungunya and Zika were introduced in the last decade, more than half of the population lives in areas at risk. The objective of this study was to characterize Aedes spp. vectors and study their natural infection with dengue, Zika and chikungunya in Ibagué, a Colombian city and capital of the department of Tolima, with case reports of simultaneous circulation of these three arboviruses. METHODS: Mosquito collections were carried out monthly between June 2018 and May 2019 in neighborhoods with different levels of socioeconomic status. We used the non-parametric Friedman, Mann-Whitney and Kruskal-Wallis tests to compare mosquito density distributions. We applied logistic regression analyses to identify associations between mosquito density and absence/presence of breeding sites, and the Spearman correlation coefficient to analyze the possible relationship between climatic variables and mosquito density. RESULTS: We collected Ae. aegypti in all sampled neighborhoods and found for the first time Ae. albopictus in the city of Ibagué. A greater abundance of mosquitoes was collected in neighborhoods displaying low compared to high socioeconomic status as well as in the intradomicile compared to the peridomestic space. Female mosquitoes predominated over males, and most of the test females had fed on human blood. In total, four Ae. aegypti pools (3%) were positive for dengue virus (serotype 1) and one pool for chikungunya virus (0.8%). Interestingly, infected females were only collected in neighborhoods of low socioeconomic status, and mostly in the intradomicile space. CONCLUSIONS: We confirmed the co-circulation of dengue (serotype 1) and chikungunya viruses in the Ae. aegypti population in Ibagué. However, Zika virus was not detected in any mosquito sample, 3 years after its introduction into the country. The positivity for dengue and chikungunya viruses, predominance of mosquitoes in the intradomicile space and the high proportion of females fed on humans highlight the high risk for arbovirus transmission in Ibagué, but may also provide an opportunity for establishing effective control strategies.

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Zika virus (ZIKV) was recently introduced into the Western Hemisphere, where it is suspected to be transmitted mainly by Aedes aegypti in urban environments. ZIKV represents a public health problem as it has been implicated in congenital microcephaly in South America since 2015. Reports of ZIKV transmission in forested areas of Africa raises the possibility of its dispersal to non-human-modified environments in South America, where it is now endemic. The current study aimed to detect arboviruses in mosquitoes collected from areas with low human interference in Rio de Janeiro, Brazil. Using a sensitive pan-flavivirus RT-PCR, designed to detect the NS5 region, pools of Ae. albopictus and Haemagogus leucocelaenus, were positive for both ZIKV and yellow fever (YFV). Virus RNA was detected in pools of adult males and females reared from field-collected eggs. Findings presented here suggest natural vertical transmission and infection of ZIKV in Hg. leucocelaenus and Ae.albopitcus in Brazil.