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1.
Mem Inst Oswaldo Cruz ; 115: e200070, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667462

RESUMO

BACKGROUND Nyssorhynchus deaneorum is a potential malaria vector because it has been shown to be competent to transmit Plasmodium vivax and Plasmodium falciparum, and because it exhibits antropophilic and endophilic behaviors in some regions of the Amazon. This profile makes Ny. deaneorum a useful mosquito for experiments that model Plasmodium-vector interactions in the Amazon. OBJECTIVE Herein we describe how a free-mating colony of Ny. deaneorum has been established using an automated light stimulation system. METHODS Mosquitoes were captured in São Francisco do Guaporé, Rondônia. The F1 generation was reared until adult emergence at which point copulation was induced using an automatic copulation induction system (ACIS). FINDINGS After four generations, natural mating and oviposition began to occur without light stimulation. The number of pupae and adult mosquitoes increased from the F5 to F10 generations. The new Ny. deaneorum colony exhibited susceptibility to P. vivax. MAIN CONCLUSIONS Automated light stimulation is an effective method for establishing an Ny. deaneorum colony under laboratory conditions as it produces enough adults to create a stenogamic colony. The establishment of a stable, P. vivax-susceptible colony of Ny. deaneorum makes it possible to model parasite-vector interactions and to test novel drug therapies that target parasite development in mosquitoes.


Assuntos
Anopheles/parasitologia , Copulação/fisiologia , Malária , Mosquitos Vetores/parasitologia , Oviposição , Animais , Anopheles/fisiologia , Brasil , Feminino , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/fisiologia , Plasmodium falciparum , Plasmodium vivax
2.
J Insect Sci ; 20(3)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32559297

RESUMO

Wolbachia is a maternally inherited bacterium ubiquitous in insects that has attracted interest as a prospective insect pest-control agent. Here, we detected and characterized Wolbachia in the leafhoppers Matsumuratettix hiroglyphicus (Matsumura) (Cicadellidae: Hemiptera) and Yamatotettix flavovittatus Matsumura (Cicadellidae: Hemiptera), insect vectors of the phytoplasma that cause white leaf disease in sugarcane. The 16S rRNA and wsp gene markers revealed that Wolbachia was not present in the M. hiroglyphicus but naturally occurs in Y. flavovittatus. Additionally, the infection rates in adult leafhoppers ranged from 0 to 100% depending on geographic location. Moreover, Wolbachia was detected in the eggs and first- to fifth-instar nymphs of Y. flavovittatus. A phylogenic tree of Wolbachia indicated that it resided in the monophyletic supergroup B clade and clustered in the Ori subgroup. Furthermore, fluorescence in situ hybridization revealed that Wolbachia localized to the egg apices, randomly distributed in the egg cytoplasm, and was concentrated in the nymph and adult bacteriomes, as well as occasional detection in the thorax and abdomen. To the best of our knowledge, the present study is the first to demonstrate the prevalence of Wolbachia in the leafhopper Y. flavovittatus. The obtained results would provide useful information for the future development of Wolbachia as a biological control agent for the leafhopper vectors.


Assuntos
Hemípteros/microbiologia , Simbiose , Wolbachia/fisiologia , Animais , Feminino , Hemípteros/crescimento & desenvolvimento , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/microbiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Óvulo/crescimento & desenvolvimento , Óvulo/microbiologia , Doenças das Plantas/microbiologia , Saccharum/microbiologia
3.
Enferm. clín. (Ed. impr.) ; 30(supl.5): 34-40, jun. 2020. mapas, tab
Artigo em Inglês | IBECS | ID: ibc-196470

RESUMO

Background of study: As an effort of prevention of Dengue Fever Occurence, it must be applied an information system which is able to give fast, exact, complete, and easy understood information. Because of that, it needs to be developed a Geographical Information System {Sistem Informasi Geografis (SIG)} in society health service, that is related to the distribution and risking factors of Dengue Fever Occurence. The Geographical Information System model can show the description of spacial distribution of Dengue Fever cases in a district, the tendency of illness spreading, and whether there is clustering of the illness or not, so it can identify unsafe/susceptible level in a district to Dengue Fever Occurrence. METHOD: The design of this research is observational analytic with Cross Sectional approach, using Geographical Information System in spacial analysis. The samples of the research are all dengue fever victims recorded at public health centre in Ngemplak Subdistrict, Boyolali Regency from 2016 to 2017, which are 93 respondents. The data analysis is done by univariate, bivariate with Contingency Coefficient test and spacial analysis in Geographical Information System approach. THE RESULT OF THE STUDY: The result of the recearch shows risking factors that is proved significantly related to dengue fever occurence. Those are population density percentage (p = 0.003) and the number of free mosquito larva percentage (p = 0.001). Spacialy, districts in Ngemplak Subdistrict, Boyolali, that have highest susceptible level to dengue fever are Sindon and Gagak Sipat village


No disponible


Assuntos
Humanos , Dengue/epidemiologia , Dengue/prevenção & controle , Controle de Doenças Transmissíveis/organização & administração , Insetos Vetores/crescimento & desenvolvimento , Indonésia/epidemiologia , Sistemas de Informação Geográfica/estatística & dados numéricos , Aedes/patogenicidade
5.
PLoS Negl Trop Dis ; 14(5): e0008324, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32463829

RESUMO

Local anomalies in rainfall and temperature induced by El Niño and La Niña episodes could change the structure of the vector community. We aimed to estimate the effect of the El Niño-La Niña cycle in the potential distribution of cutaneous leishmaniasis (CL) vector species in Colombia and to compare the richness of the vectors with the occurrence of CL in the state of Norte de Santander. The potential distributions of four species were modeled using a MaxEnt algorithm for the following episodes: La Niña 2010-2011, Neutral 2012-2015 and El Niño 2015-2016. The relationship between the potential richness of the vectors and the occurrence of CL in Norte de Santander was evaluated with a log-binomial regression model. During the El Niño 2015-2016 episode, Lutzomyia ovallesi and Lutzomyia panamensis increased their distribution into environmentally suitable areas, and three vector species (Lutzomyia gomezi, Lutzomyia ovallesi and Lutzomyia panamensis) showed increases in the range of their altitudinal distribution. During the La Niña 2010-2011 episode, a reduction was observed in the area suitable for occupation by Lutzomyia gomezi and Lutzomyia spinicrassa. During the El Niño 2015-2016 episode, the occurrence of at least one CL case was related to a higher percentage of rural localities showing a richness of vectors = 4. The anomalies in rainfall and temperature induced by the episodes produced changes in the potential distribution of CL vectors in Colombia. In Norte de Santander, during Neutral 2012-2015 and El Niño 2015-2016 episodes, a higher probability of at least one CL case was related to a higher percentage of areas with a greater richness of vectors. The results help clarify the effect of the El Niño-La Niña cycle in the dynamics of CL in Colombia and emphasize the need to monitor climate variability to improve the prediction of new cases.


Assuntos
El Niño Oscilação Sul , Insetos Vetores/crescimento & desenvolvimento , Leishmaniose Cutânea/epidemiologia , Psychodidae/crescimento & desenvolvimento , Animais , Colômbia/epidemiologia , Humanos
6.
PLoS One ; 15(4): e0231251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32287300

RESUMO

Outdoor residual spraying is proposed for the control of exophilic mosquitoes. However, the residual effect of insecticide mists applied to outdoor resting habitats of mosquitoes is not well characterized. The objective of this study was to assess the longevity of the residual insecticidal effect of three pyrethroid formulations applied to outdoor vegetation against the Southeast Asian malaria vector Anopheles dirus. Lambda-cyhalothrin capsule suspension, deltamethrin emulsifiable concentrate and bifenthrin wettable powder were sprayed on dense bamboo bushes on the Thailand-Myanmar border during the dry season 2018. The duration and magnitude of the residual insecticidal effect were assessed weekly with a standard cone assay, using freshly collected insecticide-treated bamboo leaves and a laboratory-adapted colony of Anopheles dirus sensu stricto susceptible to pyrethroids. The experiment was repeated during the rainy season to assess the persistence of the lambda-cyhalothrin formulation after natural rains and artificial washings. During the dry season (cumulative rainfall = 28 mm in 111 days), mortality and knockdown (KD) rates were >80% for 60 days with bifenthrin and 90 days with lambda-cyhalothrin and deltamethrin. The 50% knockdown time (TKD50) was <15 min with lambda-cyhalothrin and deltamethrin, and <30 min with bifenthrin. During the rainy season (cumulative rainfall = 465 mm in 51 days), mortality and KD rates were >80% for 42 days and TKD50 was <15 min with lambda-cyhalothrin. Additional artificial washing of the testing material with 10L of tap water before performing the cone tests had no significant effect on the residual insecticidal effect of this formulation. Long-lasting residual insecticidal effect can be obtained when spraying pyrethroid insecticides on the outdoor resting habitats of malaria vectors.


Assuntos
Anopheles/efeitos dos fármacos , Insetos Vetores/efeitos dos fármacos , Resistência a Inseticidas , Inseticidas/farmacologia , Controle de Mosquitos/métodos , Nitrilos/farmacologia , Piretrinas/farmacologia , Animais , Anopheles/crescimento & desenvolvimento , Insetos Vetores/crescimento & desenvolvimento , Inseticidas/química , Mianmar , Nitrilos/química , Piretrinas/química , Tailândia
7.
J Med Entomol ; 57(1): 25-32, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31602460

RESUMO

Laboratory rearing procedures of Culicoides stellifer Coquillett (Diptera: Ceratopogonidae) were evaluated with an aim towards colonization of this species. Eggs collected from field-collected gravid females were placed on 0.25% agar slants and given a diet of 1) nematodes (Panagrellus redivivus Linnaeus), 2) nematodes + lactalbumin and yeast (LY), 3) microbes from nematode medium, and 4) tap water (autoclaved). Complete larval development to adult stage occurred only in two treatments: 1) nematodes and 2) nematodes + LY. Culicoides stellifer larvae could not survive beyond 1 wk on a diet of microbes alone or in the sterile water treatment. Larval survival rates were high using nematode diet (79.2 ± 11.3% [mean ± SE]) but were slightly lower in the nematode + LY group (66.5 ± 19.6%). Larval stage lasted ~21 d in both treatments. Sex ratio of F1 adults was ~1:1 (M:F) using nematode diet but was male biased (~2:1) with nematode + LY diet. These findings collectively suggest that a microbial community is required for midge larvae, either to support invertebrate prey base or as a potential food source. But in the present study, the supplied microbes alone were not sufficient to support midge survival/development. It appears that other nutritional components may also be essential to support the larval survival/development of C. stellifer. Overall, a simple diet of bacterial feeding nematodes and their associated microorganisms can be used to rear C. stellifer larvae under laboratory conditions. However, captive mating in F1 adults poses a major obstacle for successful colonization of this species currently.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Ceratopogonidae/crescimento & desenvolvimento , Insetos Vetores/crescimento & desenvolvimento , Traços de História de Vida , Animais , Dieta , Orbivirus , Estados Unidos
8.
J Med Entomol ; 57(1): 33-38, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31603199

RESUMO

This study reports the third collection of Triatoma nitida Usinger in Mexico, with a brief description of the collection area and an investigation of parameters related to its vectorial capacity. Whether a triatomine (Hemiptera: Reduviidae) species is a primary or secondary vector is determined by factors that include vectorial capacity, anthropophilic habits, geographic distribution, and capacity to invade and colonize human dwellings. However, when the primary vectors are removed, secondary vectors, such as T. nitida, can become important transmitters of Trypanosoma cruzi Chagas to humans. To estimate the vectorial capacity of T. nitida, the egg-to-adult development time, number of blood meals required to molt to the adult stage, accumulative mortality, onset time for feeding, and feeding and defecation times were examined. Triatoma nitida (n = 100) required a median of 590 d to complete its development time, with a median of 31 blood meals. Almost half (46.5%) of the nymphs died during the cycle. The onset of feeding time exceeded 5 min in all nymphal instars (except on fourth-instar) and adults and feeding times exceeded 22 min in all instars, except on first-instar nymphs. No defecation was observed for 65.6% (n = 383) of the triatomines during a 30-min observation period. Based on the six parameters, the vectorial capacity of T. nitida should be considered as low. However, surveillance programs should include this species because the potential importance of T. nitida as a vector has been demonstrated in other countries.


Assuntos
Insetos Vetores/fisiologia , Traços de História de Vida , Triatoma/fisiologia , Distribuição Animal , Animais , Doença de Chagas , Comportamento Alimentar , Feminino , Insetos Vetores/crescimento & desenvolvimento , Masculino , México , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Triatoma/crescimento & desenvolvimento
9.
PLoS Negl Trop Dis ; 13(12): e0007902, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31834879

RESUMO

Trypanosoma cruzi is the causative agent of Chagas disease, a Neglected Tropical Disease affecting 8 million people in the Americas. Triatomine hematophagous vectors feed on a high diversity of vertebrate species that can be reservoirs or dead-end hosts, such as avian species refractory to T. cruzi. To understand its transmission dynamics in synanthropic and domesticated species living within villages is essential to quantify disease risk and assess the potential of zooprophylaxis. We developed a SI model of T. cruzi transmission in a multi-host community where vector reproduction and parasite transmission depend on a triatomine blood-feeding rate accounting for vector host preferences and interference while feeding. The model was parameterized to describe T. cruzi transmission in villages of the Yucatan peninsula, Mexico, using the information about Triatoma dimidiata vectors and host populations accumulated over the past 15 years. Extensive analyses of the model showed that dogs are key reservoirs and contributors to human infection, as compared to synanthropic rodents and cats, while chickens or other domesticated avian hosts dilute T. cruzi transmission despite increasing vector abundance. In this context, reducing the number of dogs or increasing avian hosts abundance decreases incidence in humans by up to 56% and 39%, respectively, while combining such changes reduces incidence by 71%. Although such effects are only reached over >10-years periods, they represent important considerations to be included in the design of cost-effective Integrated Vector Management. The concomitant reduction in T. cruzi vector prevalence estimated by simulating these zooprophylactic interventions could indeed complement the removal of colonies from the peridomiciles or the use of insect screens that lower vector indoor abundance by ~60% and ~80%. These new findings reinforce the idea that education and community empowerment to reduce basic risk factors is a cornerstone to reach and sustain the key objective of interrupting Chagas disease intra-domiciliary transmission.


Assuntos
Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Doença de Chagas/transmissão , Reservatórios de Doenças/parasitologia , Transmissão de Doença Infecciosa , Insetos Vetores/crescimento & desenvolvimento , Triatoma/crescimento & desenvolvimento , Animais , Doença de Chagas/veterinária , Simulação por Computador , Humanos , Incidência , México
10.
PLoS Negl Trop Dis ; 13(12): e0007903, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31805051

RESUMO

BACKGROUND: Several modeling studies have been undertaken to assess the feasibility of the WHO goal of eliminating gambiense human African trypanosomiasis (g-HAT) by 2030. However, these studies have generally overlooked the effect of vector migration on disease transmission and control. Here, we evaluated the impact of vector migration on the feasibility of interrupting transmission in different g-HAT foci. METHODS: We developed a g-HAT transmission model of a single tsetse population cluster that accounts for migration of tsetse fly into this population. We used a model calibration approach to constrain g-HAT incidence to ranges expected for high, moderate and low transmission settings, respectively. We used the model to evaluate the effectiveness of current intervention measures, including medical intervention through enhanced screening and treatment, and vector control, for interrupting g-HAT transmission in disease foci under each transmission setting. RESULTS: We showed that, in low transmission settings, under enhanced medical intervention alone, at least 70% treatment coverage is needed to interrupt g-HAT transmission within 10 years. In moderate transmission settings, a combination of medical intervention and a vector control measure with a daily tsetse mortality greater than 0.03 is required to achieve interruption of disease transmission within 10 years. In high transmission settings, interruption of disease transmission within 10 years requires a combination of at least 70% medical intervention coverage and at least 0.05 tsetse daily mortality rate from vector control. However, the probability of achieving elimination in high transmission settings decreases with an increased tsetse migration rate. CONCLUSION: Our results suggest that the WHO 2030 goal of G-HAT elimination is, at least in theory, achievable. But the presence of tsetse migration may reduce the probability of interrupting g-HAT transmission in moderate and high transmission foci. Therefore, optimal vector control programs should incorporate monitoring and controlling of vector density in buffer areas around foci of g-HAT control efforts.


Assuntos
Migração Animal , Transmissão de Doença Infecciosa/prevenção & controle , Controle de Insetos/métodos , Insetos Vetores/crescimento & desenvolvimento , Tripanossomíase Africana/prevenção & controle , Moscas Tsé-Tsé/crescimento & desenvolvimento , Animais , Simulação por Computador , Erradicação de Doenças , Humanos , Incidência , Tripanossomíase Africana/transmissão
11.
Acta Trop ; 200: 105177, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31539526

RESUMO

The parasite manipulation hypothesis states that the parasite modifies host's behavior thereby increasing the probability that the parasite will pass from an intermediate host to its final host. We used the kissing bugs Triatoma pallidipennis and T. longipennis and two isolates of the Trypanosoma cruzi parasite (Chilpancingo and Morelos) to test these ideas. These insects are intermediate hosts of this parasite, which is the causal agent of Chagas disease. The Chilpancingo isolate is more pathogenic than the Morelos isolate, in the bugs. We expected that infected bugs would be more active and likely at detecting human-like odors. Given the differences in pathogenicity between isolates, we expected the Chilpancingo isolate to induce these effects more strongly and lead to higher parasite number than the Morelos isolate. Finally, infected bugs would gain less mass (a mechanism thought to increase bite rate, and thus transmission) than non-infected bugs. Having determined that both isolate haplotypes belong to the Tc1a group, we found that: (a) young instars of both species were more active and likely to detect human odor when they were infected, regardless of the isolate; (b) there was no difference in parasite abundance depending on isolate; and, (c) infected bugs did not end up with less weight than uninfected bugs. These results suggest that T. cruzi can manipulate the bugs, which implies a higher risk to contract Chagas disease than previously thought.


Assuntos
Comportamento Animal , Interações Hospedeiro-Parasita , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/parasitologia , Triatoma/crescimento & desenvolvimento , Triatoma/parasitologia , Trypanosoma cruzi/parasitologia , Animais , Doença de Chagas/transmissão , Humanos , México
12.
J Med Entomol ; 56(5): 1384-1388, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31322659

RESUMO

The etiologic agent of Chagas disease, Trypanosoma cruzi, is transmitted by hematophagous insect vectors that subsist on repeated blood meals over their lives separated by periods of fasting. Using naturally infected Mepraia spinolai, we measured the influence of parasite infection on this host vector's mortality during regular feeding and after fasting. After their capture, the insects were fed twice with uninfected mice to evaluate parasitic infection in their fecal samples by microscopic observation and PCR. Then the insects were subjected to a fasting period, followed by a third (final) feeding. After each feeding, a fecal sample was obtained to evaluate T. cruzi infection. To determine its progress through ontogeny, mortality and ecdysis of the infected and uninfected nymphs and adults were recorded on three occasions, over 140 d, and analyzed. Detections of infection by T. cruzi between the two first feedings increased, but this detection level was generally reduced after final feeding unless reinfected. For nymphs (stages III-V), their mortality was highest when infected after the fasting period, whereas adults were equally resistant to death after fasting when infected with T. cruzi. Metacyclic trypomastigotes were principally excreted in the fecal samples. Our results confirm that T. cruzi is pathogenic to its invertebrate hosts under nutritional stress conditions, when nymphs' mortality is higher while infected than uninfected when they were hungry. These results are epidemiologically important because T. cruzi harms the fasting vector M. spinolai, reducing its lifespan and competence as a disease vector, and thereby its rates of parasite transmission.


Assuntos
Insetos Vetores/fisiologia , Triatominae/fisiologia , Trypanosoma cruzi/fisiologia , Animais , Doença de Chagas , Jejum , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/parasitologia , Longevidade , Ninfa/crescimento & desenvolvimento , Ninfa/parasitologia , Ninfa/fisiologia , Triatominae/crescimento & desenvolvimento , Triatominae/parasitologia
13.
Microbiologyopen ; 8(10): e899, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31271530

RESUMO

The small hive beetle (SHB) is an opportunistic parasite that feeds on bee larvae, honey, and pollen. While SHBs can also feed on fruit and other plant products, like its plant-feeding relatives, SHBs prefer to feed on hive resources and only reproduce inside bee colonies. As parasites, SHBs are inevitably exposed to bee-associated microbes, either directly from the bees or from the hive environment. These microbes have unknown impacts on beetles, nor is it known how extensively beetles transfer microbes among their bee hosts. To identify sets of beetle microbes and the transmission of microbes from bees to beetles, a metagenomic analysis was performed. We identified sets of herbivore-associated bacteria, as well as typical bee symbiotic bacteria for pollen digestion, in SHB larvae and adults. Deformed wing virus was highly abundant in beetles, which colonize SHBs as suggested by a controlled feeding trial. Our data suggest SHBs are vectors for pathogen transmission among bees and between colonies. The dispersal of host pathogens by social parasites via floral resources and the hive environment increases the threats of these parasites to honey bees.


Assuntos
Abelhas/microbiologia , Abelhas/parasitologia , Besouros/microbiologia , Insetos Vetores/microbiologia , Insetos Vetores/virologia , Microbiota , Animais , Bactérias/classificação , Bactérias/genética , Besouros/crescimento & desenvolvimento , Insetos Vetores/crescimento & desenvolvimento , Metagenômica , Vírus de RNA/genética
14.
Acta Trop ; 198: 105097, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325415

RESUMO

An appropriate management strategy of bluetongue vectors should include larvicidal treatments in their larval development sites utilizing active substances with low environmental impact. A selection of biorational insecticides with potential against dipteran larvae was assayed in the laboratory against field collected Culicoides larvae including C. cataneii, C. circumscriptus, and C. imicola, determining their median lethal concentrations in water and mud/water substrate. The efficacy of formulations containing the insect growth regulators pyriproxyfen and cyromazine, the botanical insecticide azadirachtin, and the entomopathogenic bacteria Bacillus thuringiensis israelensis and Brevibacillus laterosporus, was also assessed in field conditions in a comparative study conducted in sheep farm larval development sites, including treatments with the organophosphate temephos. Significant larvicidal properties were associated with the various insecticides evaluated in the laboratory assays and in field trials, although with different levels of effectiveness. While temephos was confirmed to be an effective broad spectrum larvicidal substance, B. laterosporus appeared to be the most effective among entomopathogens, while insect growth regulators combined a good efficacy to a long-lasting residual effect in the field. Everything considered, the use of these biorational insecticides alone or in combination with larval habitat manipulation techniques appears to be a promising method to complement integrated biting midge management programs.


Assuntos
Ceratopogonidae/efeitos dos fármacos , Inseticidas/farmacologia , Animais , Ecossistema , Controle de Insetos/métodos , Insetos Vetores/efeitos dos fármacos , Insetos Vetores/crescimento & desenvolvimento , Inseticidas/administração & dosagem , Inseticidas/química , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Solo/química , Água/química
15.
PLoS Negl Trop Dis ; 13(6): e0007314, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31194743

RESUMO

BACKGROUND: The Mediterranean Basin is historically a hotspot for trade, transport, and migration. As a result, countries surrounding the Mediterranean Sea share common public health threats. Among them are vector-borne diseases, and in particular, mosquito-borne viral diseases are prime candidates as (re)emerging diseases and are likely to spread across the area. Improving preparedness and response capacities to these threats at the regional level is therefore a major issue. The implementation of entomological surveillance is, in particular, of utmost importance. Guidance in designing entomological surveillance systems is critical, and these systems may pursue different specific objectives depending on the disease. The purpose of the proposed review is to draw up guidelines for designing effective and sustainable entomological surveillance systems in order to improve preparedness and response. However, we make it clear that there is no universal surveillance system, so the thinking behind harmonisation is to define evidence-based standards in order to promote best practises, identify the most appropriate surveillance activities, and optimise the use of resources. Such guidance is aimed at policymakers and diverse stakeholders and is intended to be used as a framework for the implementation of entomological surveillance programmes. It will also be useful to collaborate and share information with health professionals involved in other areas of disease surveillance. Medical entomologists and vector control professionals will be able to refer to this report to advocate for tailored entomological surveillance strategies. The main threats targeted in this review are the vectors of dengue virus, chikungunya virus, Zika virus, West Nile virus, and Rift Valley fever virus. The vectors of all these arboviruses are mosquitoes. METHODS: Current knowledge on vector surveillance in the Mediterranean area is reviewed. The analysis was carried out by a collaboration of the medical entomology experts in the region, all of whom belong to the MediLabSecure network, which is currently funded by the European Union and represents an international effort encompassing 19 countries in the Mediterranean and Black Sea region. FINDINGS: Robust surveillance systems are required to address the globalisation of emerging arboviruses. The prevention and management of mosquito-borne viral diseases must be addressed in the prism of a One Health strategy that includes entomological surveillance as an integral part of the policy. Entomological surveillance systems should be designed according to the entomological and epidemiological context and must have well-defined objectives in order to effect a tailored and graduated response. We therefore rely on different scenarios according to different entomological and epidemiological contexts and set out detailed objectives of surveillance. The development of multidisciplinary networks involving both academics and public authorities will provide resources to address these health challenges by promoting good practises in surveillance (identification of surveillance aims, design of surveillance systems, data collection, dissemination of surveillance results, evaluation of surveillance activities) and through the sharing of effective knowledge and information. These networks will also contribute to capacity building and stronger collaborations between sectors at both the local and regional levels. Finally, concrete guidance is offered on the vector of the main arbovirus based on the current situation in the area.


Assuntos
Transmissão de Doença Infecciosa , Monitoramento Epidemiológico , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/virologia , Viroses/transmissão , Vírus/isolamento & purificação , Animais , Humanos , Insetos Vetores/classificação , Região do Mediterrâneo , Vírus/classificação
16.
J Med Entomol ; 56(6): 1565-1570, 2019 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-31227827

RESUMO

Triatominae bugs (Hemiptera: Reduviidae) are usually associated with different vertebrate species, upon which many of them feed. Yet how these different blood meal sources influence key biological parameters is rarely investigated for triatomines. To fill this knowledge gap, this study sought to determine the effect of a domestic rat species (Rattus norvegicus Berkenhout (Rodentia: Muridae)), a domestic mice species (Mus musculus L. (Rodentia: Muridae)), and chickens (Gallus gallus domesticus L. (Galliformes: Phasianidae)), as blood meal sources upon several biological parameters (development time, number of required blood meals to moult and feeding and defecation behaviors) of the Mexican major vector Triatoma barberi Usinger. The three studied cohorts' development times were similar (325-338 d), but the number of required blood meals to moult (21), as well as the total mortality rate (26%), were both the highest in the cohort that fed on chickens. The longevity of females (186-190 d) was similar among the three studied cohorts, as was that of males. The median time elapsed between the presentation of a blood meal source and onset of feeding (10 min) was similar among the three studied cohorts, as were their feeding times and defecation patterns. Most of our studied parameters demonstrate how T. barberi can effectively take advantage of feeding on rodents as much as it does on hens. Those parameter results also show that T. barberi should be considered as a potential yet underappreciated vector in some areas, thus warranting a surveillance program of its current distribution area in Mexico.


Assuntos
Insetos Vetores/fisiologia , Traços de História de Vida , Triatoma/fisiologia , Animais , Doença de Chagas/transmissão , Galinhas , Defecação , Comportamento Alimentar , Feminino , Insetos Vetores/crescimento & desenvolvimento , Longevidade , Masculino , Camundongos , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Ratos , Triatoma/crescimento & desenvolvimento
17.
Geospat Health ; 14(1)2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-31099510

RESUMO

Infectious diseases transmitted by vectors/intermediate hosts constitute a major part of the economic burden related to public health in the endemic countries of the tropics, which challenges local welfare and hinders development. The World Health Organization, in partnership with pharmaceutical companies, major donors, endemic countries and non-governmental organizations, aims to eliminate the majority of these infections in the near future. To succeed, the ecological requirements and real-time distributions of the causative agents (bacteria, parasites and viruses) and their vectors must not only be known to a high degree of accuracy, but the data must also be updated more rapidly than has so far been the case. Current approaches include data collection through terrestrial capture on site and satellite-generated information. This article provides an update of currently available sources of remotely-sensed data, including specific information on satellite-borne sensors, and how such data can be handled by Geographical Information Systems (GIS). Computers, when equipped with GIS software based on common spatial denominators, can connect remotely-sensed environmental records with terrestrial-captured data and apply spatial statistics in ways uniquely suited to manage control activities in areas where vector-borne infections dominate.


Assuntos
Doenças Transmissíveis/epidemiologia , Sistemas de Informação Geográfica/organização & administração , Doenças Transmitidas por Vetores/epidemiologia , Animais , Ecossistema , Monitoramento Ambiental/instrumentação , Humanos , Insetos Vetores/crescimento & desenvolvimento , Solo , Tempo (Meteorologia)
18.
Methods Mol Biol ; 1971: 351-368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30980314

RESUMO

Sand fly colonies are of major importance for experimental studies on biology, behavior, vector competence, relationship with Leishmania parasites, and vector control. This chapter is intended to provide methods and techniques used to initiate, establish, and maintain sand fly colonies. Details on collecting sand flies for colonization, colony initiation, maintenance, and experimental infection of Phlebotomus spp. with Leishmania spp. are reported.


Assuntos
Insetos Vetores , Leishmania/crescimento & desenvolvimento , Phlebotomus , Animais , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/parasitologia , Phlebotomus/crescimento & desenvolvimento , Phlebotomus/parasitologia
19.
Pathog Glob Health ; 113(2): 49-57, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30916639

RESUMO

Climatic changes, landscape management, massive human, animal and commodity transportation represent important factors which are contributing to the spread of zoonotic diseases. The environmental and socioeconomic factors affecting the incidence of vector-borne zoonoses and possibilities for the reduction of disease impacts are discussed in the article. The most important zoonoses with expanding area of incidence and/or increasing occurrence are summarized, with special emphasis on the European region. While some diseases and their respective pathogens are indigenous to Europe (e.g. Lyme disease), others have been introduced to Europe from tropical areas (e.g. chikungunya or dengue fever). These emerging diseases may represent a serious threat in near future and better understanding of their spreading mechanisms, pathogenesis and consequent treatment is very important.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/transmissão , Insetos Vetores/crescimento & desenvolvimento , Zoonoses/epidemiologia , Zoonoses/transmissão , Animais , Mudança Climática , Europa (Continente)/epidemiologia , Saúde Global , Incidência
20.
J Med Entomol ; 56(3): 617-624, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30768666

RESUMO

Chagas disease is caused by Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae). It is transmitted to humans primarily through contaminated feces of blood-sucking vectors of the subfamily Triatominae, known in Ecuador as 'chinchorros'. Some Triatominae species can adapt to domiciliary and peridomiciliary environments where T. cruzi can be transmitted to humans. Triatoma carrioni (Larrousse 1926) colonizes domestic and peridomestic habitats up to 2,242 m above sea level (masl) in southern Ecuador (Loja Province) and northern Peru. This study describes the life cycle, feeding, and defecation patterns of T. carrioni under controlled laboratory conditions using mice as hosts. Specimens were collected in Loja Province, Ecuador, and maintained in the laboratory. The life cycle was approximately 385.7 ± 110.6 d. There was a high mortality rate, 40.9% for first instars and 38.9% for fifth instars (NV). Feeding and defecation patterns for each life stage were examined by recording: insertion time of the proboscis into the host, total feeding time, time to first defecation, and weight of the bloodmeal. Total feeding time varied between 20.6 ± 11.4 min for first instars (NI) and 48.9 ± 19.0 min for adult females. The time to first defecation was variable but ranged from 9.8 ± 10.6 min for NI to 39.4 ± 24.7 min for NV during feeding. This suggests that T. carrioni has an annual life cycle and is a potential vector of T. cruzi in Loja Province. Improved knowledge of populations of T. carrioni in domestic and peridomestic environments of Ecuador can have a significant impact on the prevention and control of Chagas disease.


Assuntos
Insetos Vetores/fisiologia , Estágios do Ciclo de Vida , Triatoma/fisiologia , Animais , Doença de Chagas , Defecação , Comportamento Alimentar , Insetos Vetores/crescimento & desenvolvimento , Triatoma/crescimento & desenvolvimento , Trypanosoma cruzi/fisiologia
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