Research

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19 pages, 3564 KiB

Open AccessArticle

High Abundance of Haemoproteus Parasites in Culicoides (Diptera, Ceratopogonidae), with a Confirmation of Culicoides reconditus as a New Vector of These Avian Blood Parasites

by Carolina Romeiro Fernandes Chagas, Mélanie Duc, Margarita Kazak, Kristina Valavičiūtė-Pocienė, Dovilė Bukauskaitė, Carolina Hernández-Lara and Rasa Bernotienė

Insects 2024, 15(3), 157; https://doi.org/10.3390/insects15030157 - 26 Feb 2024

Viewed by 918

Abstract

Haemoproteus parasites are the most diverse among Haemosporida. However, their natural vectors (Culicoides) are still poorly investigated and were identified for only a few parasite species and lineages. The application of an integrative approach (insect dissection, microscopic analysis, and molecular-based methods) [...] Read more.

Haemoproteus parasites are the most diverse among Haemosporida. However, their natural vectors (Culicoides) are still poorly investigated and were identified for only a few parasite species and lineages. The application of an integrative approach (insect dissection, microscopic analysis, and molecular-based methods) is necessary in these studies, which have been carried out by a few research groups, mainly in Europe. The aim of this study was (i) to determine the Culicoides species that are naturally infected by Haemoproteus parasites, and which can support its complete sporogonic development, and (ii) to investigate the prevalence of Culicoides species and Haemoproteus parasite lineages in different study sites. In total, 1953 parous Culicoides females, from 11 species, were collected in four different localities in Lithuania and were dissected and analyzed using an integrative approach. The most abundant was C. pictipennis (30.3%). Parasite DNA was found in 7.9% of all investigated Culicoides, of which ~30% had sporozoites in their salivary glands, confirming their vector competence for these parasites. The Botanical Garden presented the highest number of Culicoides parous females, Culicoides species, and parasite lineages, as well as the highest positivity for sporozoites. Culicoides reconditus was confirmed as a natural vector of Haemoproteus parasites, sporozoites of six Haemoproteus lineages were reported for the first time, and 12 new interactions between Haemoproteus parasite lineages and Culicoides species were identified. Haemoproteus parasites seem to be transmitted by a high number of Culicoides species, with C. kibunensis, C. pictipennis, and C. segnis being the most important vectors. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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16 pages, 4198 KiB

Open AccessArticle

The SisaMob Information System: Implementation of Digital Data Collection as a Tool for Surveillance and Vector Control in the State of São Paulo

by Gerson Laurindo Barbosa, Antônio Henrique Alves Gomes and Vera Lucia Fonseca de Camargo-Neves

Insects 2023, 14(4), 380; https://doi.org/10.3390/insects14040380 - 13 Apr 2023

Viewed by 1232

Abstract

Information systems are essential instruments in managing resources, in the evaluation of the epidemiological situation, and for decision-making at all hierarchical levels. Technological advances have allowed the development of systems that meet these premises. Therefore, it is recommended to consider the optimization of [...] Read more.

Information systems are essential instruments in managing resources, in the evaluation of the epidemiological situation, and for decision-making at all hierarchical levels. Technological advances have allowed the development of systems that meet these premises. Therefore, it is recommended to consider the optimization of data entry and its immediate georeferencing in order to obtain information in real time. To meet this objective, we describe the application introduction process for the implementation of the digital collection of primary data and its integration with the database through synchronization with the SisaWeb platform (Information System for surveillance and control of Aedes aegypti), developed to meet the needs of the Arbovirus Surveillance and Control Program in the state of São Paulo, Brazil. For this purpose, the application—SisaMob—was conceived in the Android Studio development environment, Google^®, following the same guidelines as the traditional collection method. Tablets equipped with the Android^® operating system were used. To evaluate the implementation of the application, a semi-structured test was applied. The results highlighted that 774.9% (27) of the interviewees evaluated its use positively and, replacing the standard bulletin, 61.1% (22) of the users considered it regular to excellent. The automatic collection of geographic coordinates represented the greatest innovation in the use of the portable device, with reductions in errors and in the time taken to complete the report in the field. The integration to SisaWeb allowed obtaining information in real-time, being easily presented in tabular and graphic modes and spatially arranged through maps, making it possible to monitor the work at a distance, and allowing preliminary analyses during the data collection process. For the future, we must improve the mechanisms for assessing the effectiveness of information, increase the potential of the tool to produce more accurate analyses, which can direct actions more efficiently. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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14 pages, 2195 KiB

Open AccessArticle

DNA Barcoding of Morphologically Characterized Mosquitoes Belonging to the Genus Mansonia from the Atlantic Forest and Brazilian Savanna

by Karin Kirchgatter, Lilian de Oliveira Guimarães, Eliana Ferreira Monteiro, Vanessa Christe Helfstein, Juliana Telles-de-Deus, Regiane Maria Tironi de Menezes, Simone Liuchetta Reginato, Carolina Romeiro Fernandes Chagas and Vera Lucia Fonseca de Camargo-Neves

Insects 2023, 14(2), 109; https://doi.org/10.3390/insects14020109 - 20 Jan 2023

Cited by 1 | Viewed by 2089

Abstract

The identification of mosquito species is necessary for determining the entomological components of disease transmission. However, identification can be difficult in species that are morphologically similar. The cytochrome c oxidase subunit I (COI) DNA barcode region is considered a valuable and [...] Read more.

The identification of mosquito species is necessary for determining the entomological components of disease transmission. However, identification can be difficult in species that are morphologically similar. The cytochrome c oxidase subunit I (COI) DNA barcode region is considered a valuable and reliable diagnostic tool for mosquito species recognition, including those that belong to species complexes. Mansonia mosquitoes are found in forests near swampy areas. They are nocturnal and are highly attracted to light. Hematophagous adult females exhibit aggressive biting behavior and can become infected with and transmit pathogens during their feeding, including some epizootic viruses and avian malaria. In Brazil, twelve Mansonia species have been reported. In a recent study from the São Paulo Zoo in Brazil, three morphologically distinct species were collected and identified, namely: Mansonia (Mansonia) indubitans, Ma. (Man.) pseudotitillans and Ma. (Man.) titillans. However, confirmation of these species by molecular identification was unsuccessful due to a lack of COI sequences in the GenBank database. Thus, this research aimed to describe the COI DNA barcode sequences of some morphologically characterized Mansonia (Man.) species from Brazil and to determine their utility in delimiting species collected from the Atlantic Forest and Brazilian Savanna. Accordingly, we provide tools for the genetic identification of species that play a significant role in pathogen transmission in wildlife and potentially humans. We show that the delimitation of Mansonia species via five different approaches based on COI DNA sequences (BI, NJ, ASAP, bPTP and GMYC) yield basically the same groups identified by traditional taxonomy, and we provide the identification of specimens that were previously identified only up to the subgenus level. We also provide COI sequences from two Mansonia species that were not previously available in sequence databases, Ma. wilsoni and Ma. pseudotitillans, and thus contribute to the ongoing global effort to standardize DNA barcoding as a molecular means of species identification. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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10 pages, 752 KiB

Open AccessArticle

Pyrethroid Susceptibility in Stomoxys calcitrans and Stomoxys indicus (Diptera: Muscidae) Collected from Cattle Farms in Southern Thailand

by Sokchan Lorn, Warin Klakankhai, Pitunart Nusen, Anchana Sumarnrote and Krajana Tainchum

Insects 2022, 13(8), 711; https://doi.org/10.3390/insects13080711 - 07 Aug 2022

Cited by 6 | Viewed by 1863

Abstract

The susceptibility to six pyrethroid insecticides (permethrin, deltamethrin, alpha-cypermethrin, cypermethrin, lambda-cyhalothrin, and bifenthrin), each at the recommended concentration, was evaluated for two stable fly species—Stomoxys calcitrans (Linnaeus, 1758) and Stomoxys indicus Picard, 1908 (Diptera: Muscidae)—through tarsal contact using a World Health Organization [...] Read more.

The susceptibility to six pyrethroid insecticides (permethrin, deltamethrin, alpha-cypermethrin, cypermethrin, lambda-cyhalothrin, and bifenthrin), each at the recommended concentration, was evaluated for two stable fly species—Stomoxys calcitrans (Linnaeus, 1758) and Stomoxys indicus Picard, 1908 (Diptera: Muscidae)—through tarsal contact using a World Health Organization (WHO) cone bioassay procedure. The field populations of S. calcitrans were collected from the Songkhla and Phattalung provinces, while S. indicus were collected from the Phattalung and Satun provinces in Thailand. The stable flies were exposed to insecticide-treated filter paper for 30 min, and their knockdown counts at 30 min and 60 min and mortality counts at 12 h and 24 h were recorded. The S. calcitrans and S. indicus Songkhla and Phattalung populations were moderately susceptible to pyrethroids, as indicated by the 24 h mortality. Nonetheless, the Satun population of S. indicus was completely susceptible to permethrin, with 100% mortality, and showed the lowest susceptibility to deltamethrin and bifenthrin. The results indicate the generally low susceptibility of stable flies to pyrethroids in the southern provinces of Thailand. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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17 pages, 3012 KiB

Open AccessArticle

The Use of “Tail-Pedometers” to Evaluate the Impact of Dipterans in Feeder Cattle

by Marc Desquesnes, Kornkanok Thaisungnoen, Piangjai Chalermwong, Adèle Nevot, Clément Fossaert, Antoine Lucas, Sathaporn Onju, Phoompong Boonsaen and Sathaporn Jittapalapong

Insects 2022, 13(7), 616; https://doi.org/10.3390/insects13070616 - 08 Jul 2022

Viewed by 1397

Abstract

Hematophagous flies are a pest for livestock; their direct impact reduces productivity, and they are vectors of parasites, bacteria and viruses. Their control using insecticides is inefficient and highly polluting. The validation of new control tools requires efficacy and cost-effectiveness evaluation. The quantification [...] Read more.

Hematophagous flies are a pest for livestock; their direct impact reduces productivity, and they are vectors of parasites, bacteria and viruses. Their control using insecticides is inefficient and highly polluting. The validation of new control tools requires efficacy and cost-effectiveness evaluation. The quantification of hematophagous insects’ impact in livestock is a challenging prerequisite. Tail flicks counts can reliably evaluate fly-burden; however, visual records are tedious and time-consuming. In the present study, automation of tail flick counts was made through the use of pedometers attached to the tail, in two groups of feeder cattle. Group A was kept in a pen under the protection of a mosquito net, and Group B was kept in an open-air pen. The fly density of Group B was evaluated using fly traps. The apparent density per trap ranged from 130 to 1700 in the study. The mean pedometer records per 24 h ranged from 957+/−58 bits in Group A to 11,138+/−705 bits in Group B. The night/day records observed in Group A (200/800 bits) were drastically increased in Group B (1000–4000/4000–14,000 bits) and variable along seasons. A very high correlation was observed between fly density and visual records or pedometer records (PR). Two-hour PRs proved to be a reliable predictive tool for fly density. Moreover, the pedometers revealed an unsuspected but significant nuisance of mosquitoes, which should be thoroughly investigated. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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13 pages, 623 KiB

Open AccessArticle

Utilization of Pomelo (Citrus maxima) Peel Waste into Bioactive Essential Oils: Chemical Composition and Insecticidal Properties

by Naduvilthara U. Visakh, Berin Pathrose, Arunaksharan Narayanankutty, Ahmed Alfarhan and Varsha Ramesh

Insects 2022, 13(5), 480; https://doi.org/10.3390/insects13050480 - 20 May 2022

Cited by 27 | Viewed by 18010

Abstract

The wastes generated during the post-harvest handling of various agricultural commodities is rather under-utlilized. The peels of citrus fruits are often discarded as waste. Citrus peels are rich in essential oils and exhibit toxicity towards various insect species. The essential oils are also [...] Read more.

The wastes generated during the post-harvest handling of various agricultural commodities is rather under-utlilized. The peels of citrus fruits are often discarded as waste. Citrus peels are rich in essential oils and exhibit toxicity towards various insect species. The essential oils are also an eco-friendly option for insect pest management. The Citrus maxima peel essential oil (CMEO), a waste product, characterized it, and evaluated its potential for insect pest management. The major terpenoids present in CMEO are Limonene and α-Pinene. The CMEO displayed potentials in controlling the insect pests via contact and fumigant toxicity. Moreover, CMEO showed significant larvicidal activities against Culex tritaeniorhynchus and Aedes aegypti species of mosquitoes; however, Armigeres subalbatus was more resistant. The biological safety of the essential oil was also tested against the stored seeds, where no significant inhibition of seed germination was noticed compared to the control. Utilizing a waste product such as citrus peel for pest management can achieve the dual objective of waste utilization and eco-friendly pest management. Overall, the CMEO is therefore found to be a bioactive essential oil extracted from the wastes of pomelo (C. maxima). Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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14 pages, 3332 KiB

Open AccessArticle

Culex Flavivirus Isolation from Naturally Infected Mosquitoes Trapped at Rio de Janeiro City, Brazil

by Cinthya Amaral, Daniel Câmara, Tiago Salles, Marcelo Damião Meneses, Carlla de Araújo-Silva, Vanessa Dias, Fábio da Costa, Lúcio Caldas and Renata Azevedo

Insects 2022, 13(5), 477; https://doi.org/10.3390/insects13050477 - 19 May 2022

Cited by 1 | Viewed by 1991

Abstract

Culex Flavivirus (CxFV) is a classical insect-specific virus, which has aroused interest after the first indication that it can produce in nature superinfection exclusion of viruses of medical interest such as West Nile. Despite the detection of CxFV in different regions, CxFV ecology [...] Read more.

Culex Flavivirus (CxFV) is a classical insect-specific virus, which has aroused interest after the first indication that it can produce in nature superinfection exclusion of viruses of medical interest such as West Nile. Despite the detection of CxFV in different regions, CxFV ecology and the influence of co-circulation of arboviruses remains poorly understood. Therefore, our primary goals are to observe the occurrence of CxFV infection in mosquitoes trapped in an urban area of Rio de Janeiro, Brazil, characterize the virus circulating, and provide isolates. A prospective study was carried out for eight months on the campus of the Federal University of Rio de Janeiro, trapping adult mosquitoes. The CxFV minimum infection rates were determined in this period, and the virus isolation process is fully described. Samples from this study were grouped into genotype 2, along with CxFV sequences from Latin America and Africa. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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22 pages, 1359 KiB

Open AccessArticle

Modeling of Control Efforts against Rhipicephalus sanguineus, the Vector of Rocky Mountain Spotted Fever in Sonora Mexico

by Gerardo Alvarez-Hernandez, Alejandro Villegas Trejo, Vardayani Ratti, Michael Teglas and Dorothy I. Wallace

Insects 2022, 13(3), 263; https://doi.org/10.3390/insects13030263 - 07 Mar 2022

Cited by 5 | Viewed by 2044

Abstract

Rocky Mountain spotted fever (RMSF) is a significant health problem in Sonora, Mexico. The tick vector, Rhipicephalus sanguineus, feeds almost exclusively on domestic dogs that, in this region, also serve as the reservoir for the tick-borne pathogen, Rickettsia rickettsii. A process-based [...] Read more.

Rocky Mountain spotted fever (RMSF) is a significant health problem in Sonora, Mexico. The tick vector, Rhipicephalus sanguineus, feeds almost exclusively on domestic dogs that, in this region, also serve as the reservoir for the tick-borne pathogen, Rickettsia rickettsii. A process-based mathematical model of the life cycle of R. sanguineus was developed to predict combinations of insecticidal dog collars and long-lasting insecticidal wall treatments resulting in suppression of indoor tick populations. Because of a high burden of RMSF in a rural community near the Sonora state capital of Hermosillo, a test area was treated with a combination of insecticidal dog collars and long-lasting insecticidal wall treatments from March 2018 to April 2019, with subsequent reduction in RMSF cases and deaths. An estimated 80% of the dogs in the area had collars applied and 15% of the houses were treated. Data on tick abundance on walls and dogs, collected during this intervention, were used to parameterize the model. Model results show a variety of treatment combinations likely to be as successful as the one carried out in the test community. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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13 pages, 8930 KiB

Open AccessArticle

Evaluation of Methods to Collect Diurnal Culicidae (Diptera) at Canopy and Ground Strata, in the Atlantic Forest Biome

by Juliana Telles de Deus, Luís Filipe Mucci, Simone Lucheta Reginatto, Mariza Pereira, Eduardo Sterlino Bergo and Vera Lucia Fonseca de Camargo-Neves

Insects 2022, 13(2), 202; https://doi.org/10.3390/insects13020202 - 16 Feb 2022

Cited by 2 | Viewed by 1825

Abstract

Hand-held insect nets are the standard method for capturing vector mosquitoes of sylvatic arboviruses; however, occupational risks and biases due to individual skill and attractiveness are important limitations. The use of chemical attractants and automatic traps could be an alternative to resolve these [...] Read more.

Hand-held insect nets are the standard method for capturing vector mosquitoes of sylvatic arboviruses; however, occupational risks and biases due to individual skill and attractiveness are important limitations. The use of chemical attractants and automatic traps could be an alternative to resolve these limitations. This study compares the yields achieved using nets with those employing electrical traps with CO₂ and BG-Lure^®, near the ground and in the canopy strata (6.0 and 8.0 m high). The study was conducted at the Cantareira State Park, which is in the Brazilian Atlantic Forest biome. In the 18 collections performed, 3570 specimens of 52 taxa were obtained. The most frequent species captured near the ground were Wyeomyia confusa and Limatus durhamii, whereas Sabethes albiprivus, Sabethes purpureus, and Haemagogus leucocelaenus were the most frequent in the canopy. The nets resulted in greater species richness and abundance, followed by the trap employing CO₂. The combination of CO₂ traps with BG-Lure^® did not improve performance. The use of BG-Lure^® alone resulted in low abundance and a low number of species. Our results demonstrate that the use of traps with CO₂ can be complementary to collections with nets; however, for species of epidemiological interest such as those of the genera Haemagogus and Sabethes, especially in the canopy, the net remains the method of choice. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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14 pages, 2876 KiB

Open AccessArticle

Isolation and Characterization of Mosquito-Associated Spiroplasma cantharicola from Aedes japonicus Collected in Hokkaido, Japan

by Makoto Shimooka, Yoshimi Sakurai, Yasukazu Muramatsu and Leo Uchida

Insects 2021, 12(12), 1056; https://doi.org/10.3390/insects12121056 - 25 Nov 2021

Cited by 1 | Viewed by 2094

Abstract

Species of the genus Spiroplasma are common within arthropods and plants worldwide. Mosquito-associated Spiroplasma spp. have been reported to show pathogenicity toward mosquitoes, which serve as vectors of several infectious diseases that have detrimental effects on public health. Although Spiroplasma spp. are expected [...] Read more.

Species of the genus Spiroplasma are common within arthropods and plants worldwide. Mosquito-associated Spiroplasma spp. have been reported to show pathogenicity toward mosquitoes, which serve as vectors of several infectious diseases that have detrimental effects on public health. Although Spiroplasma spp. are expected to have potential use as biological vector-control tools, characteristics such as their distribution, host species, and cytopathogenic effects (CPEs) are not well understood. In this study, we isolated a Spiroplasma sp. from a female Aedes japonicus collected in Hokkaido, northern Japan. Phylogenetic analysis based on the 16S rRNA gene sequence indicated our isolate was closely related to S. cantharicola. We screened 103 mosquito pools consisting of 3 genera and 9 species, but only detected S. cantharicola in the first isolation. In an in vitro assay, our isolate grew well at 28 °C, but no propagation was observed at 37 °C. Furthermore, the isolate showed strong CPE on a mosquito-derived cultured cell line (C6/36), and its propagation slightly increased when co-cultured with C6/36 cells. To our knowledge, this is the third report of the isolation of S. cantharicola from mosquitoes and the first case in Asia. Our findings provide epidemiological data on S. cantharicola distribution in the region. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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12 pages, 1679 KiB

Open AccessArticle

Updating Ecological and Behavioral Aspects of the Sandfly Fauna in the Vale do Ribeira Region, São Paulo State, Brazil

by Byara Freitas Guedes Oliveira, Maria de Fátima Domingos, Fredy Galvis Ovallos and Vera Lucia Fonseca de Camargo-Neves

Insects 2021, 12(11), 988; https://doi.org/10.3390/insects12110988 - 02 Nov 2021

Cited by 1 | Viewed by 1578

Abstract

Some ecological parameters and the distribution of vectors in the municipality of Eldorado, Vale do Ribeira Region, São Paulo, were studied. Entomological surveys were carried out from September 2019 to March 2021. It was observed that a few ecological parameters, including richness, abundance, [...] Read more.

Some ecological parameters and the distribution of vectors in the municipality of Eldorado, Vale do Ribeira Region, São Paulo, were studied. Entomological surveys were carried out from September 2019 to March 2021. It was observed that a few ecological parameters, including richness, abundance, diversity, and equitability, were typical of a modified environment, where artificial ecotopes maintain the presence of sandflies throughout the year. A total of 11,668 sandflies were captured. The presence of five taxa were observed in Eldorado, with low diversity and high dominance of Nyssomyia intermedia next to Ny. neivai, which are sympatric species. The results presented reinforce the importance of these species in anthropized areas in the transmission of cutaneous leishmaniasis (CL) agents and the need for entomological monitoring. Psathyromyia pascalei was encountered for the first time in the municipality, expanding the known area of distribution of this species in a modified environment. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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Review

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10 pages, 454 KiB

Open AccessReview

Spotted Fever Group Rickettsioses in Central America: The Research and Public Health Disparity among Socioeconomic Lines

by Kyndall C. Dye-Braumuller, Marvin S. Rodríguez Aquino, Stella C. W. Self, Mufaro Kanyangarara and Melissa S. Nolan

Insects 2022, 13(8), 674; https://doi.org/10.3390/insects13080674 - 27 Jul 2022

Cited by 2 | Viewed by 1796

Abstract

Tick-borne diseases including rickettsial diseases are increasing in incidence worldwide. Many rickettsial pathogens can cause disease which is commonly underdiagnosed and underreported; Rickettsia pathogens in the spotted fever group (SFGR) are thus classified as neglected bacterial pathogens. The Central American region shoulders a [...] Read more.

Tick-borne diseases including rickettsial diseases are increasing in incidence worldwide. Many rickettsial pathogens can cause disease which is commonly underdiagnosed and underreported; Rickettsia pathogens in the spotted fever group (SFGR) are thus classified as neglected bacterial pathogens. The Central American region shoulders a large proportion of the global neglected disease burden; however, little is known regarding SFGR disease here. Although development varies, four of the seven countries in this region have both the highest poverty rates and SFGR disease burdens (El Salvador, Honduras, Guatemala, and Nicaragua), compared to Belize, Panama, and Costa Rica. Utilizing the Human Development Index (HDI), we compared published articles related to SFGR Rickettsia prevalence in the lowest-HDI-scoring countries to the highest-HDI-scoring countries. Our analysis identified a distinct dichotomy in publication, and by proxy, potentially awareness and knowledge of SFGR tick-borne disease in Central America, where the least-developed countries are at the highest risk for, yet the most vulnerable to, SFGR disease. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

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