Entomological surveillance of mosquitoes (Diptera: Culicidae), vectors of arboviruses, in an ecotourism park in Cachoeiras de Macacu, state of Rio de Janeiro-RJ, Brazil

Arboviruses are arthropod-dependent viruses to complete their zoonotic cycle. Among the transmitting arthropods, culicids stand out, which participate in the cycle of several arboviruses that can affect humans. The present study aimed to identify species of culicidae and to point out the risk of circulation, emergency, or reemergence of pathogenic arboviruses to humans in the region of the Jequitibá headquarters of the Parque Estadual dos Três Picos (PETP), in Cachoeiras de Macacu, state of Rio de Janeiro, Brazil. Sampling was carried out at five Sample Points (SP) demarcated on trails from the headquarters, with CDC light traps, HP model with dry ice attached to the side, for 48 hours of activity each month. Additionally, active catches were made with a castro catcher in the period of one hour per day in the field, from six to eleven o’clock in the morning, in each PM. After the captures, thematic map was assembled using the ArcGIS 10 software and performing a multidimensional scaling (MDS). A total of 1151 specimens were captured and the presence of culicids already incriminated as vectors of arboviruses circulating in the region was observed: Aedes fluviatilis Lutz, 1904 (71 specimens); Aedes scapularis Rondani, 1848 (55 specimens); Haemagogus leococelaenus Dyar and Shannon, 1924 (29 specimens). In addition to the subgenus Culex (culex) spp. (163 specimens). In this sense, we highlight the importance of strengthening the actions of continuous entomological surveillance of the emergence and re-emergence of new arboviruses in ecotourism visitation parks.

First Description of the Mitogenome and Phylogeny of Culicinae Species from the Amazon Region

The Culicidae family is distributed worldwide and comprises about 3587 species subdivided into the subfamilies Anophelinae and Culicinae. This is the first description of complete mitochondrial DNA sequences from Aedes fluviatilis, Aedeomyia squamipennis, Coquillettidia nigricans, Psorophora albipes, and Psorophora ferox. The mitogenomes showed an average length of 15,046 pb and 78.02% AT content, comprising 37 functional subunits (13 protein coding genes, 22 tRNAs, and two rRNAs). The most common start codons were ATT/ATG, and TAA was the stop codon for all PCGs. The tRNAs had the typical leaf clover structure, except tRNASer1. Phylogeny was inferred by analyzing the 13 PCGs concatenated nucleotide sequences of 48 mitogenomes. Maximum likelihood and Bayesian inference analysis placed Ps. albipes and Ps. ferox in the Janthinosoma group, like the accepted classification of Psorophora genus. Ae. fluviatilis was placed in the Aedini tribe, but was revealed to be more related to the Haemagogus genus, a result that may have been hampered by the poor sampling of Aedes sequences. Cq. nigricans clustered with Cq. chrysonotum, both related to Mansonia. Ae. squamipennis was placed as the most external lineage of the Culicinae subfamily. The yielded topology supports the concept of monophyly of all groups and ratifies the current taxonomic classification.

Aedes Fluviatilis Cell Lines As New Tools To Study Metabolic And Immune Interactions In Mosquito-Wolbachia Symbiosis

In the present work, we established two novel embryonic cell lines from the mosquito Aedes fluviatilis containing or not the naturally occurring symbiont bacteria Wolbachia, which were called wAflu1 and Aflu2, respectively. We also obtained wAflu1 without Wolbachia after tetracycline treatment, named wAflu1.tet. Morphofunctional characterization was performed to help elucidate the symbiont-host interaction in the context of energy metabolism regulation and molecular mechanisms of the immune responses involved. The presence of Wolbachia pipientis improves energy performance in A. fluviatilis cells; it affects the regulation of key energy sources such as lipids, proteins, and carbohydrates, increasing the speed of cell proliferation, making the distribution of actin more peripheral and with more extensions that come into contact with neighboring cells. Additionally, innate immunity mechanisms were activated, showing that the wAflu1 and wAflu1.tet cells are responsive after the stimulus using Gran negative bacteria. Therefore, this work confirms the natural, mutually co-regulating symbiotic relationship between W. pipientis and A. fluviatilis, modulating the host metabolism and immune pathway activation. The results presented here add important resources to the current knowledge of Wolbachia-arthropod interactions.

Aedes fluviatilis cell lines as new tools to study metabolic and immune interactions in mosquito-Wolbachia symbiosis

In the present work, we established two novel embryonic cell lines from the mosquito Aedes fluviatilis containing or not the naturally occurring symbiont bacteria Wolbachia, which were called wAflu1 and Aflu2, respectively. We also obtained wAflu1 without Wolbachia after tetracycline treatment, named wAflu1.tet. Morphofunctional characterization was performed to help elucidate the symbiont-host interaction in the context of energy metabolism regulation and molecular mechanisms of the immune responses involved. The presence of Wolbachia pipientis improves energy performance in A. fluviatilis cells; it affects the regulation of key energy sources such as lipids, proteins, and carbohydrates, making the distribution of actin more peripheral and with extensions that come into contact with neighboring cells. Additionally, innate immunity mechanisms were activated, showing that the wAflu1 and wAflu1.tet cells are responsive after the stimulus using Gram negative bacteria. Therefore, this work confirms the natural, mutually co-regulating symbiotic relationship between W. pipientis and A. fluviatilis, modulating the host metabolism and immune pathway activation. The results presented here add important resources to the current knowledge of Wolbachia-arthropod interactions.

ESTRUTURA DE COMUNIDADES E ESPÉCIES INDICADORAS DE CULICÍDEOS (DIPTERA: NEMATOCERA) EM AMBIENTES COM DIFERENTES GRAUS DE IMPACTO AMBIENTAL

Os culicídeos são insetos hematófagos chamados de mosquitos. Eles são vetores responsáveis pela transmissão de diversos patógenos aos animais e ao homem. As fêmeas destes dípteros fazem oviposição em recipientes introduzidos pelo humano no ambiente natural. Estes reservatórios de água transformam-se em novos criadouros. Desta forma, o objetivo desta pesquisa é descrever a diversidade de espécies de culicídeos no município de Ribeirão Claro, Paraná, encontradas em criadouros artificiais instalados em ambientes com diferentes níveis de impacto antrópico. Foram instaladas armadilhas em quatro pontos da cidade com características urbanas, periurbanas, rurais e silvestres respectivamente e em cada ponto distribuíram-se três recipientes artificiais para servir de criadouros. A captura das larvas nestes recipientes foi realizada quinzenalmente, sendo o período de coleta desenvolvido de fevereiro a setembro de 2018. As métricas de comunidade realizadas foram: riqueza, abundância total e relativa, diversidade, equitabilidade, dominância e a similaridade. Também foi analisada a presença de espécies indicadoras para cada ambiente avaliado. Foram coletados 472 culicídeos imaturos, distribuídos nos taxa: Aedes aegypti (Linnaeus, 1762), Aedes albopictus (Skuse, 1894), Culex quinquefasciatus Say, 1823, Culex coronator Dyar & Knab, 1906, Toxorhynchites sp., Anopheles argyritarsis Robineau-Desvoidy, 1827, Aedes fluviatilis (Lutz, 1904) e Uranotaenia sp. A maior abundância ocorreu na área periurbana sendo a espécie Aedes aegypti a de maior ocorrência. Foram apontados como bioindicadores o Aedes aegypti para o ambiente periurbano, o Aedes albopictus para a área rural e o Toxorhynchites sp. para o ambiente silvestre. A maior riqueza e diversidade foram observadas no ambiente silvestre mostrando que alterações nestes locais podem favorecer a presença de insetos de importância para a saúde pública.