Mosquito Behavior and Vertebrate Microbiota Interaction: Implications for Pathogen Transmission

The microbiota is increasingly recognized for its ability to influence host health and individual fitness through multiple pathways, such as nutrient synthesis, immune system development, and even behavioral processes. Most of these studies though focus on the direct effects microbiota has on its host, but they do not consider possible interactions with other individuals. However, host microbiota can change not only host behavior but also the behavior of other individuals or species toward the host. For example, microbes can have an effect on animal chemistry, influencing animal behaviors mediated by chemical communication, such as mosquito attraction. We know that host skin microbes play a major role in odor production and thus can affect the behavior of mosquitoes leading to differences in attraction to their hosts. Ultimately, the vector feeding preference of mosquitoes conditions the risk of vertebrates of coming into contact with a vector-borne pathogen, affecting its transmission, and thus epidemiology of vector-borne diseases. In this mini review, I provide an overview of the current status of research on the interaction between mosquito behavior and host skin microbiota, both in humans and other vertebrates. I consider as well the factors that influence vertebrate skin microbiota composition, such as sex, genetic makeup, and infection status, and discuss the implications for pathogen transmission.

Informasi Terkini Anopheles barbirostris dan Potensi Penularan Malaria pada Beberapa Provinsi di Indonesia

Anopheles barbirostris (An. barbirostris) is a malaria vector in several provinces in Indonesia. Bionomics An. barbirostris vary from region to region. The difference between bionomic and mosquito behavior affects the potential of An. barbirostris as a vector of malaria. The latest information about An. barbirostris is needed to determine the potential for malaria transmission in several provinces in Indonesia. The aim of the research was to get the latest information on An. barbirostris and the potential for malaria transmission in several provinces in Indonesia. Mosquitoes catching was carried out in several provinces in Indonesia using the human landing collection method, catching around livestocks, animal bited traps, light traps and morning resting. Larvae surveys were conducted in a place that had the potential for breeding ground place for An. barbirostris. Analysis of the presence of Plasmodium in An. barbirostris was performed using PCR. The examination results showed that An. barbirostris positive Plasmodium in South Sulawesi and Central Kalimantan. An. barbirostris’s behavior tended to be found to suck blood outside the home and some had been known to suck blood from people indoors. Fluctuation and density of An.barbirostris in April and June varied in the Provinces of West Papua, Central Kalimantan, North Kalimantan, South Sulawesi, Bali, Spesial Region of Yogyakarta (DIY), DKI Jakarta, Riau, Jambi, and Riau Islands. In general, An. barbirostris were known to suck the blood of people and animals with different percentages in each province. The breeding ground for An. barbirostris were found in rice fields, ponds, ditchesm and rivers. The potential for malaria transmission to be transmitted by An. barbirostris can occur in the provinces of South Sulawesi and Central Kalimantan. Abstrak Anopheles barbirostris (An. barbirostris) merupakan salah satu vektor malaria di beberapa provinsi di Indonesia. Bionomik An. barbirostris berbeda-beda di setiap wilayah. Perbedaan bionomik dan perilaku nyamuk berpengaruh terhadap potensi An. barbirostris sebagai vektor malaria. Informasi terkini tentang An. barbirostris sangat diperlukan untuk mengetahui potensi penularan malaria di beberapa provinsi di Indonesia. Tujuan penelitian adalah mendapatkan informasi terkini An. barbirostris dan potensi penularan malaria di beberapa provinsi di Indonesia. Penangkapan nyamuk dilakukan di beberapa provinsi di Indonesia menggunakan metode human landing collection, penangkapan di sekitar ternak, animal bited trap, light trap, dan resting morning. Survei jentik dilakukan di tempat yang berpotensi sebagai tempat perkembangbiakan An. barbirostris. Analisis keberadaan Plasmodium pada An. barbirostris dilakukan dengan menggunakan PCR. Hasil pemeriksaan menunjukkan bahwa An. barbirostris positif Plasmodium di Sulawesi Selatan dan Kalimantan Tengah. Perilaku An. barbirostris cenderung ditemukan menghisap darah di luar rumah dan sebagian diketahui menghisap darah orang di dalam rumah. Fluktuasi dan kepadatan An. barbirostris koleksi bulan April dan Juni berbeda-beda di Provinsi Papua Barat, Kalimantan Tengah, Kalimantan Utara, Sulawesi Selatan, Bali, Daerah Istimewa Yogyakarta (DIY), DKI Jakarta, Riau, Jambi, dan Kepulauan Riau. Secara umum An. barbirostris diketahui menghisap darah orang dan hewan dengan persentase yang berbeda-beda di setiap provinsi. Tempat perkembangbiakan An.barbirostris ditemukan di sawah, kolam, parit dan sungai. Potensi penularan malaria yang ditularkan An. barbirostris dapat terjadi di Provinsi Sulawesi Selatan dan Kalimantan Tengah.

Microbial interactions in the mosquito gut determine Serratia colonization and blood-feeding propensity

How microbe–microbe interactions dictate microbial complexity in the mosquito gut is unclear. Previously we found that, Serratia, a gut symbiont that alters vector competence and is being considered for vector control, poorly colonized Aedes aegypti yet was abundant in Culex quinquefasciatus reared under identical conditions. To investigate the incompatibility between Serratia and Ae. aegypti, we characterized two distinct strains of Serratia marcescens from Cx. quinquefasciatus and examined their ability to infect Ae. aegypti. Both Serratia strains poorly infected Ae. aegypti, but when microbiome homeostasis was disrupted, the prevalence and titers of Serratia were similar to the infection in its native host. Examination of multiple genetically diverse Ae. aegypti lines found microbial interference to S. marcescens was commonplace, however, one line of Ae. aegypti was susceptible to infection. Microbiome analysis of resistant and susceptible lines indicated an inverse correlation between Enterobacteriaceae bacteria and Serratia, and experimental co-infections in a gnotobiotic system recapitulated the interference phenotype. Furthermore, we observed an effect on host behavior; Serratia exposure to Ae. aegypti disrupted their feeding behavior, and this phenotype was also reliant on interactions with their native microbiota. Our work highlights the complexity of host–microbe interactions and provides evidence that microbial interactions influence mosquito behavior.

Mosquito Behavior of Mansonia and Anopheles and Its Relationship With the Filariasis Disease in Taniwel Timur District and Taniwel, Seram barat regency

Mansonia mosquitoes are in endemic forest and swamp areas, dirty environments and unused fish farming areas, Mansonia mosquitoes are aggressive and suck blood when humans are at night, outside the home. Anopheles actively seeks blood during illness and at night. This research uses survey and cross sectional research, it discusses to study mosquitoes, the density of mosquitoes mansonia and anopheles, as well as looking at the development of disease (prevalence) of filariasis. The population in this study is the population and population of mosquito mansonia and anopheles in East Taniwel and Taniwel Districts. Filariasis in Taniwel and East Taniwel Sub-districts, West Seram District was reported in local health centers of around 15 people. The outbreak of filariasis in Taniwel District around 2010-2019. Mansonia bleeds people at home when sick at 18: 00-18: 45. While outside the house at night 20: 00-20: 45. While Anopheles mosquitoes bite humans, at dusk and at night at 16.00-24.00, The peak is 02.00-03.00. The density of mansonia mosquitoes in Sohuwe Village, 4.00 - 5.85, Lumalatal 5.00 - 6.60 and Maloang 4.00-5.50 (moderate), Anopheles in Sohuwe 7.00-9.85, Lumalatal 5.89- 6.82, Maloang 5.00-6.50 (high). The prevalence of filariasis in Sohuwe 0.66, Lumlat 0.88. and Maloang 1.54. There is a relationship between attitudes and community relations with filariasis

A Survey of Chemoreceptive Responses on Different Mosquito Appendages

Research on the functions of insect chemoreceptors have primarily focused on antennae (olfactory receptors) and mouthparts (gustatory receptors). However, chemoreceptive sensilla are also present on other appendages, such as the leg tarsi and the anterior wing margin, and their specific roles in chemoreception and mosquito behavior remain largely unknown. In this study, electrophysiological analyses in an electroantennogram recording format were performed on Aedes aegypti (L., Diptera: Culicidae) antennae, mouthparts, tarsi, and wings during exposure to a variety of insect repellent and attractant compounds. The results provide evidence that the tarsi and wings can sense chemicals in a gaseous form, and that the odors produce differing responses on different appendages. The most consistent and strongest response occurred when exposed to triethylamine (TEA). Antennae and mouthparts showed nearly identical responses pattern to all tested compounds, and their rank orders of effectiveness were similar to those of fore- and mid-leg tarsi. Hindleg tarsi only responded to TEA, indicating that the hind legs are not as chemoreceptive. Wings responded to a range of odorants, but with a different rank order and voltage amplitude. Insights gleaned into the function of these appendages in insect chemoreception are discussed.

A minimal 3D model of mosquito flight behavior around the human baited bed net

Advances in digitized video-tracking and behavioral analysis have enabled accurate recording and quantification of mosquito flight and host-seeking behaviors, enabling development of Individual (agent) Based Models at much finer spatial scales than previously possible. We used such quantified behavioral parameters to create a novel virtual testing model, capable of accurately simulating indoor flight behavior by a virtual population of host-seeking mosquitoes as it interacts with and responds to simulated stimuli from a human-occupied bed net. We describe the model, including base mosquito behavior, state transitions, environmental representation and host stimulus representation. In the absence of a bed net and human bait, flight distribution of the model population is relatively uniform in the arena. Introducing an unbaited net induces a change in distribution due to landing events on the net surface, predominantly occurring on the sides and edges of the net. Presence of simulated human baited net strongly impacted flight distribution patterns, exploratory foraging, the number and distribution of net landing sites, depending on the bait orientation. As recorded in live mosquito experiments, contact with baited nets (a measure of exposure to the lethal insecticide) occurred predominantly on the top surface of the net. Number of net contacts and height of contacts decreased with increasing attractant dispersal noise. Results generated by the model are an accurate representation of actual mosquito behavior recorded at and around a human-occupied bed net in untreated and insecticide treated nets. In addition to providing insights into host-seeking behavior of endophilic vectors, this fine-grained model is highly flexible and has significant potential for in silico screening of novel bed net designs, accelerating the deployment of new and more effective tools for protecting against malaria in sub-Saharan Africa.

Behavior-based control of arthropod vectors: the case of mosquitoes, ticks, and Chagasic bugs

This chapter outlines the patterns and occurrences of major diseases transmitted by arthropod vectors, highlighting the need for behavior-based control strategies, first, focusing on mosquito control tools with an emphasis on how knowledge of mosquito behavioral ecology may help vector control programmes. The potential of sound traps, swarm manipulation, ‘lure and kill’, radiation, transgenicm and symbiont-based approaches will be outlined, and how mosquito behavior influences these vector control strategies. Secondly, tick control strategies, as well as pheromone-assisted tick control will be reviewed, with special reference to pheromone-assisted matrix for application to vegetation, tick decoy, bont tick decoy, and the deployment of confusants. Thirdly, how Chagasic bugs are traditionally controlled will be summarized. Also, we highlight emerging chemical-based attraction methods, employing bug pheromones, as well as the use of entomopathogens. This review is not a thorough one, as it should only instruct students on how to use arthropod behavior to control arthropod vectors.

Peripheral, intrareceptor inhibition in mosquito olfaction

How chemical signals are integrated at the peripheral sensory system of insects is still an enigma. Here we show that when coexpressed with Orco in Xenopus oocytes, an odorant receptor from the southern house mosquito, CquiOR32, generated inward (regular) currents when challenged with cyclohexanone and methyl salicylate, whereas eucalyptol and fenchone elicited inhibitory (upward) currents. Responses of CquiOR32-CquiOrco-expressing oocytes to odorants were reduced in a dose-dependent fashion by coapplication of inhibitors. This intrareceptor inhibition was also manifested in vivo in fruit flies expressing the mosquito receptor CquiOR32, as well in neurons on the antennae of the southern house mosquito. Likewise, an orthologue from the yellow fever mosquito, AaegOR71, showed intrareceptor inhibition in the Xenopus oocyte recording system and corresponding inhibition in antennal neurons. Intrareceptor inhibition was also manifested in mosquito behavior. Blood-seeking females were repelled by methyl salicylate, but repellence was significantly reduced when methyl salicylate was coapplied with eucalyptol.One Sentence SummaryIntrareceptor inhibition was observed in mosquito odorant receptors expressed in heterologous systems, in vivo, and manifested in behavioral responses.