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1.
J Vis Exp ; (175)2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34605817

RESUMO

Insect vectors horizontally transmit many plant viruses of agricultural importance. More than one-half of plant viruses are transmitted by hemipteran insects that have piercing-sucking mouthparts. During viral transmission, the insect saliva bridges the virus-vector-host because the saliva vectors viruses, and the insect proteins, trigger or suppress the immune response of plants from insects into plant hosts. The identification and functional analyses of salivary proteins are becoming a new area of focus in the research field of arbovirus-host interactions. This protocol provides a system to detect proteins in the saliva of leafhoppers using the plant host. The leafhopper vector Nephotettix cincticeps infected with rice dwarf virus (RDV) serves as an example. The vitellogenin and major outer capsid protein P8 of RDV vectored by the saliva of N. cincticeps can be detected simultaneously in the rice plant that N. cincticeps feeds on. This method is applicable for testing the salivary proteins that are transiently retained in the plant host after insect feeding. It is believed that this system of detection will benefit the study of hemipteran-virus-plant or hemipteran-plant interactions.


Assuntos
Hemípteros , Oryza , Animais , Insetos Vetores , Insetos , Doenças das Plantas , Proteínas e Peptídeos Salivares
2.
Emerg Infect Dis ; 27(10): 2544-2553, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34545784

RESUMO

We analyzed epidemiologic characteristics and distribution of 1,067 human plague cases and 5,958 Yersinia pestis isolates collected from humans, host animals, and insect vectors during 1950-2019 in 4 Marmota plague foci in China. The case-fatality rate for plague in humans was 68.88%; the overall trend slowly decreased over time but fluctuated greatly. Most human cases (98.31%) and isolates (82.06%) identified from any source were from the Marmota himalayana plague focus. The tendency among human cases could be divided into 3 stages: 1950-1969, 1970-2003, and 2004-2019. The Marmota sibirica plague focus has not had identified human cases nor isolates since 1926. However, in the other 3 foci, Y. pestis continues to circulate among animal hosts; ecologic factors might affect local Y. pestis activity. Marmota plague foci are active in China, and the epidemic boundary is constantly expanding, posing a potential threat to domestic and global public health.


Assuntos
Peste , Yersinia pestis , Animais , China/epidemiologia , Humanos , Insetos Vetores , Marmota , Peste/epidemiologia
3.
Rev Bras Parasitol Vet ; 30(3): e007121, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34550212

RESUMO

American cutaneous leishmaniasis (ACL) is a neglected zoonotic disease caused mainly by Leishmania (Viannia) braziliensis, which is endemic throughout Brazil. Canine ACL cases were investigated in a rural area of Monte Mor, São Paulo, where a human ACL case had been confirmed. Dogs were evaluated through clinical and laboratory diagnosis including serology, cytological tissue preparations and PCR on skin lesions, lymph node and bone marrow samples. Entomological investigations on sandflies trapped in the surroundings of the study area were performed for 14 months. Nyssomyia neivai was the predominant phlebotomine species, comprising 94.65% of the captured specimens (832 out of 879). This species was the most abundant in all trapping sites, including human homes and dog shelters. Ny. whitmani, Migonemyia migonei, Pintomyia monticola, Evandromyia cortellezzii, Pi. fischeri and Expapilata firmatoi were also captured. Two of the three dogs examined were positive for anti-Leishmania IgG in ELISA using the antigen Fucose mannose ligand and skin samples were positive for L. (V.) braziliensis in PCR, but all the samples collected were negative for L. (L.) infantum. One of the dogs had a confirmed persistent infection for more than one year.


Assuntos
Doenças do Cão , Leishmania braziliensis , Leishmaniose Cutânea , Psychodidae , Animais , Brasil , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Cães , Insetos Vetores , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/veterinária
4.
East Mediterr Health J ; 27(9): 911-917, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34569047

RESUMO

Background: Sandflies are active vectors of several diseases, including leishmaniasis, which Morocco hopes to eliminate by 2030. Despite efforts to limit their spread, they still remain a public health problem in the country, as the behaviour of individuals in relation to sandflies plays an important role in the sustainability of the epidemiological cycle. Aims: To explore and determine the knowledge and behaviours related to sandfly diseases. Methods: A quantitative method was adopted using a questionnaire assisted by a personal interview. Based on the epidemiological situation of leishmaniasis cases reported in recent years in Al-Hajeb province, we conducted a field survey among 281 persons in April and May 2019 residing in the communities where the cases of the disease are registered. Results: 61.6% of Moroccans know sandflies by the name "Chniwla"; 44.1% thought that sandflies do not transmit diseases; 41.3% thought they multiplied in contaminated water; 52.7% thought sandfly bites could not be avoided; and 6.4% recognized the role of individuals in the fight against vectors. Conclusions: The need to raise public awareness of the risks of sandflies, using the popular concepts obtained to simplify scientific terms and formulate targeted health education strategies that make the individual an active player in vector control.


Assuntos
Leishmaniose , Phlebotomus , Psychodidae , Animais , Humanos , Insetos Vetores , Leishmaniose/epidemiologia , Leishmaniose/prevenção & controle , Marrocos/epidemiologia
5.
J Vis Exp ; (174)2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34515677

RESUMO

Rice stripe virus (RSV), which causes significant economic loss of agriculture in East Asia, entirely depends on insect vectors for its effective transmission among host rice. Laodelphax striatellus (small brown planthopper, SBPH) is the primary insect vector that horizontally transmits RSV while sucking sap from the phloem. Saliva plays a significant role in insects' feeding behavior. A convenient method that will be useful for research on insects' saliva with piercing-sucking feeding behavior is described here. In this method, insects were allowed to feed on an artificial diet sandwiched between two stretched paraffin film layers. The diet containing the saliva was collected each day, filtered, and concentrated for further analysis. Finally, the quality of collected saliva was examined by protein staining and immunoblotting. This method was exemplified by detecting the presence of RSV and a mucin-like protein in the saliva of SBPH. These artificial feeding and saliva collection method will lay a foundation for further research on factors in insect saliva related to feeding behavior and virus transmission.


Assuntos
Hemípteros , Oryza , Tenuivirus , Animais , Insetos Vetores , Insetos , Saliva
6.
BMC Genomics ; 22(1): 677, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34544390

RESUMO

BACKGROUND: Candidatus Liberibacter asiaticus (CLas) is one the causative agents of greening disease in citrus, an unccurable, devastating disease of citrus worldwide. CLas is vectored by Diaphorina citri, and the understanding of the molecular interplay between vector and pathogen will provide additional basis for the development and implementation of successful management strategies. We focused in the molecular interplay occurring in the gut of the vector, a major barrier for CLas invasion and colonization. RESULTS: We investigated the differential expression of vector and CLas genes by analyzing a de novo reference metatranscriptome of the gut of adult psyllids fed of CLas-infected and healthy citrus plants for 1-2, 3-4 and 5-6 days. CLas regulates the immune response of the vector affecting the production of reactive species of oxygen and nitrogen, and the production of antimicrobial peptides. Moreover, CLas overexpressed peroxiredoxin, probably in a protective manner. The major transcript involved in immune expression was related to melanization, a CLIP-domain serine protease we believe participates in the wounding of epithelial cells damaged during infection, which is supported by the down-regulation of pangolin. We also detected that CLas modulates the gut peristalsis of psyllids through the down-regulation of titin, reducing the elimination of CLas with faeces. The up-regulation of the neuromodulator arylalkylamine N-acetyltransferase implies CLas also interferes with the double brain-gut communication circuitry of the vector. CLas colonizes the gut by expressing two Type IVb pilin flp genes and several chaperones that can also function as adhesins. We hypothesized biofilm formation occurs by the expression of the cold shock protein of CLas. CONCLUSIONS: The thorough detailed analysis of the transcritome of Ca. L. asiaticus and of D. citri at different time points of their interaction in the gut tissues of the host led to the identification of several host genes targeted for regulation by L. asiaticus, but also bacterial genes coding for potential effector proteins. The identified targets and effector proteins are potential targets for the development of new management strategies directed to interfere with the successful utilization of the psyllid vector by this pathogen.


Assuntos
Citrus , Hemípteros , Rhizobiaceae , Animais , Expressão Gênica , Hemípteros/genética , Insetos Vetores/genética , Liberibacter , Doenças das Plantas , Rhizobiaceae/genética
7.
Malar J ; 20(1): 388, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34587958

RESUMO

BACKGROUND: Female mosquitoes serve as vectors for a host of illnesses, including malaria, spread by the Plasmodium parasite. Despite monumental strides to reduce this disease burden through tools such as bed nets, the rate of these gains is slowing. Ongoing disruptions related to the COVID-19 pandemic may also negatively impact gains. The following scoping review was conducted to examine novel means of reversing this trend by exploring the efficacy of insecticide-treated window screens or eaves to reduce Anopheles mosquito bites, mosquito house entry, and density. METHODS: Two reviewers independently searched PubMed, Scopus, and ProQuest databases on 10 July, 2020 for peer-reviewed studies using insecticide-treated screens or eaves in malaria-endemic countries. These articles were published in English between the years 2000-2020. Upon collection, the reports were stratified into categories of biting incidence and protective efficacy, mosquito entry and density, and mosquito mortality. RESULTS: Thirteen out of 2180 articles were included in the final review. Eaves treated with beta-cyfluthrin, transfluthrin or bendiocarb insecticides were found to produce vast drops in blood-feeding, biting or mosquito prevalence. Transfluthrin-treated eaves were reported to have greater efficacy at reducing mosquito biting: Rates dropped by 100% both indoors and outdoors under eave ribbon treatments of 0.2% transfluthrin (95% CI 0.00-0.00; p < 0.001). Additionally, co-treating window screens and eaves with polyacrylate-binding agents and with pirimiphos-methyl has been shown to retain insecticidal potency after several washes, with a mosquito mortality rate of 94% after 20 washes (95% CI 0.74-0.98; p < 0.001). CONCLUSIONS: The results from this scoping review suggest that there is value in implementing treated eave tubes or window screens. More data are needed to study the longevity of screens and household attitudes toward these interventions.


Assuntos
Anopheles/fisiologia , Habitação/normas , Insetos Vetores/fisiologia , Inseticidas , Malária/prevenção & controle , Animais , Anopheles/efeitos dos fármacos , Feminino , Mordeduras e Picadas de Insetos/prevenção & controle , Insetos Vetores/efeitos dos fármacos , Malária/transmissão
8.
An Acad Bras Cienc ; 93(4): e20191178, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495197

RESUMO

To better understand the dispersion strategies of Triatoma infestans (Klug) (Hemiptera: Reduviidae, Triatominae), we evaluated the spatial effect of infested peridomicile and density vegetation cover in a historically endemic area for Chagas disease. The study was conducted in rural houses of the northwest of Córdoba province, Argentine, during 2012-2013. Active search of triatomines were made in domicile and peridomicile habitats. To characterize vegetation coverage, a thematic map was obtained considering five types of vegetation cover (closed/open forest, closed/open shrubland and cultural land). From each house we extracted the area of vegetation coverage, housing density and infested peridomiciles density. We used generalized linear models to evaluate the effect of these variables on the occurrence of infested peridomicile. According to our results, the probability of a peridomicile to be infested increases by 1.34 (95%CI [0.98; 1.90]) times more when peridomicile structures are in environments with higher housing density and by 1.25 (95%CI [0.84; 1.88]) more times when houses are surrounded by open shrublands. Among the multiple ecological determinants of peridomestic infestation, the influence of vegetation cover has been poorly studied. In this study we discussed the effect of the vegetation as a potential modulator of the dispersion strategies of T. infestans.


Assuntos
Doença de Chagas , Triatoma , Animais , Argentina , Habitação , Humanos , Insetos Vetores , População Rural
9.
Rev Soc Bras Med Trop ; 54: e01412021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34431942

RESUMO

INTRODUCTION: This short communication presents a novel report on the occurrence of Panstrongylus rufotuberculatus in the Brazilian state of Rondônia. METHODS: Two specimens were collected inside dwellings and identified using dichotomous keys. RESULTS: The present study showed the extensive geographic distribution of P. rufotuberculatus and the increased number of species in the state of Rondônia. CONCLUSIONS: This new record of P. rufotuberculatus is important for understanding the epidemiology of Chagas disease because this species is found naturally infected with Trypanosoma cruzi. Studies on the ecology, biology, and vector-host-parasite interactions of this species are essential for surveillance programs.


Assuntos
Panstrongylus , Reduviidae , Triatominae , Animais , Brasil , Insetos Vetores
10.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361781

RESUMO

The protozoan diseases Human African Trypanosomiasis (HAT), Chagas disease (CD), and leishmaniases span worldwide and therefore their impact is a universal concern. The present regimen against kinetoplastid protozoan infections is poor and insufficient. Target-based design expands the horizon of drug design and development and offers novel chemical entities and potential drug candidates to the therapeutic arsenal against the aforementioned neglected diseases. In this review, we report the most promising targets of the main kinetoplastid parasites, as well as their corresponding inhibitors. This overview is part of the Special Issue, entitled "Advances of Medicinal Chemistry against Kinetoplastid Protozoa (Trypanosoma brucei, Trypanosoma cruzi and Leishmania spp.) Infections: Drug Design, Synthesis and Pharmacology".


Assuntos
Antiprotozoários/farmacologia , Doença de Chagas/tratamento farmacológico , Desenho de Fármacos , Leishmaniose/tratamento farmacológico , Terapia de Alvo Molecular/métodos , Tripanossomíase Africana/tratamento farmacológico , Animais , Antiprotozoários/síntese química , Antiprotozoários/classificação , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Descoberta de Drogas , Humanos , Insetos Vetores/efeitos dos fármacos , Insetos Vetores/parasitologia , Leishmania/efeitos dos fármacos , Leishmania/genética , Leishmania/crescimento & desenvolvimento , Leishmania/metabolismo , Leishmaniose/parasitologia , Leishmaniose/transmissão , Estágios do Ciclo de Vida/efeitos dos fármacos , Estágios do Ciclo de Vida/genética , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Estrutura Molecular , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Relação Estrutura-Atividade , Trypanosoma brucei gambiense/efeitos dos fármacos , Trypanosoma brucei gambiense/genética , Trypanosoma brucei gambiense/crescimento & desenvolvimento , Trypanosoma brucei gambiense/metabolismo , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/genética , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/metabolismo , Tripanossomíase Africana/parasitologia , Tripanossomíase Africana/transmissão
11.
Parasitol Res ; 120(9): 3105-3111, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34387751

RESUMO

Visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) are diseases transmitted by infected female sand flies. Since the eradication of malaria in Turkey, CL is the main vector-borne disease in the country, with more than 2000 cases per year, making it a significant public health problem. The aims of this study were to carry out an entomological survey in Antalya Province, an endemic area for CL in the Mediterranean Region of Turkey, to identify sand fly fauna and to screen female specimens for the presence of Leishmania parasites (Leishmania infantum, L. tropica, L. major, and L. donovani) using molecular analysis. Sand flies were collected in 42 localities of seven districts in Antalya Province using CDC miniature light traps in two different periods, June 2012 and September 2013. The specimens were kept in 96% ethanol until the dissection was done. The head and genitalia of the specimens were cut for preparing individual slides for species identification. The rest of the body of female specimens was kept separately. The specimens were identified at the species level, and 27 pools were generated according to the locations and species for screening the presence of Leishmania. A commercial kit was used for DNA extractions. Real-time and conventional polymerase chain reaction (PCR) targeting the internal transcribed spacer region (ITS1) were then performed. In total, 1306 specimens comprising nine species belonging to the Phlebotomus genus were collected in the study region, with Phlebotomus neglectus/syriacus (38.82%) the most abundant, followed by P. alexandri (21.67%) and P. tobbi (20.44%). In the 27 pools, Leishmania infantum DNA was detected in four pools containing P. neglectus/syriacus and one pool containing P. tobbi. In conclusion, the sand fly fauna in the Antalya Province is diverse. The probable vector sand fly species are P. neglectus/syriacus and P. tobbi with high dominance (59.26%), which indicates a high risk of CL transmission. The data presented here may help to shed more light on the transmission cycles of the Leishmania parasite in this CL endemic area.


Assuntos
Leishmania infantum , Phlebotomus , Psychodidae , Animais , Feminino , Insetos Vetores , Turquia/epidemiologia
12.
Parasitol Res ; 120(9): 3091-3103, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34405280

RESUMO

Green periurban residential areas in Mediterranean countries have flourished in the last decades and become foci for leishmaniasis. To remedy the absence of information on vector ecology in these environments, we examined phlebotomine sand fly distribution in 29 sites in Murcia City over a 3-year period, including the plots of 20 detached houses and nine non-urbanized sites nearby. We collected 5,066 specimens from five species using "sticky" interception and light attraction traps. The relative frequency of the main Leishmania infantum vector Phlebotomus perniciosus in these traps was 32% and 63%, respectively. Sand fly density was widely variable spatially and temporally and greatest in non-urbanized sites, particularly in caves and abandoned buildings close to domestic animal holdings. Phlebotomus perniciosus density in house plots was positively correlated with those in non-urbanized sites, greatest in larger properties with extensive vegetation and non-permanently lived, but not associated to dog presence or a history of canine leishmaniasis. Within house plots, sand fly density was highest in traps closest to walls. Furthermore, the study provides a guideline for insect density assessment and reporting and is envisioned as a building block towards the development of a pan-European database for robust investigation of environmental determinants of sand fly distribution.


Assuntos
Leishmania infantum , Leishmaniose , Phlebotomus , Psychodidae , Animais , Cães , Feminino , Insetos Vetores , Leishmaniose/epidemiologia , Leishmaniose/veterinária , Masculino , Espanha
13.
BMC Infect Dis ; 21(1): 846, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418974

RESUMO

BACKGROUND: A proactive approach to preventing and responding to emerging infectious diseases is critical to global health security. We present a three-stage approach to modeling the spatial distribution of outbreak vulnerability to Aedes aegypti-vectored diseases in Perú. METHODS: Extending a framework developed for modeling hemorrhagic fever vulnerability in Africa, we modeled outbreak vulnerability in three stages: index case potential (stage 1), outbreak receptivity (stage 2), and epidemic potential (stage 3), stratifying scores on season and El Niño events. Subsequently, we evaluated the validity of these scores using dengue surveillance data and spatial models. RESULTS: We found high validity for stage 1 and 2 scores, but not stage 3 scores. Vulnerability was highest in Selva Baja and Costa, and in summer and during El Niño events, with index case potential (stage 1) being high in both regions but outbreak receptivity (stage 2) being generally high in Selva Baja only. CONCLUSIONS: Stage 1 and 2 scores are well-suited to predicting outbreaks of Ae. aegypti-vectored diseases in this setting, however stage 3 scores appear better suited to diseases with direct human-to-human transmission. To prevent outbreaks, measures to detect index cases should be targeted to both Selva Baja and Costa, while Selva Baja should be prioritized for healthcare system strengthening. Successful extension of this framework from hemorrhagic fevers in Africa to an arbovirus in Latin America indicates its broad utility for outbreak and pandemic preparedness and response activities.


Assuntos
Aedes , Arbovírus , Dengue , Epidemias , Animais , Dengue/epidemiologia , Dengue/prevenção & controle , Humanos , Insetos Vetores , Mosquitos Vetores
14.
Hist Cienc Saude Manguinhos ; 28(3): 869-874, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-34346995

RESUMO

This article describes the emergence of health concerns relating to the epidemics that occurred during the twentieth century in La Pampa, a province in Argentina. Epidemics such as smallpox drove such policies, which frequently originated in Buenos Aires, the country's capital. The spread of many epidemics was due to shortages: water, sewage and adequate refuse disposal, an insufficient number of health care workers, the presence of disease transmission vectors such as mosquitos, and, ultimately, poverty. The historical experience described in this text highlights the importance of analyzing the impact of SARS-CoV-2 beyond the big cities.


Assuntos
COVID-19/história , Epidemias/história , Varíola/história , Animais , Argentina/epidemiologia , COVID-19/epidemiologia , Criança , Cidades/epidemiologia , Cidades/história , Erradicação de Doenças/história , Erradicação de Doenças/organização & administração , Feminino , Pessoal de Saúde/história , Pessoal de Saúde/estatística & dados numéricos , Política de Saúde/história , Política de Saúde/legislação & jurisprudência , História do Século XX , Humanos , Índios Sul-Americanos/história , Índios Sul-Americanos/estatística & dados numéricos , Insetos Vetores , Masculino , Militares/história , Pobreza/história , Eliminação de Resíduos/história , Esgotos , Varíola/epidemiologia , Varíola/prevenção & controle , Vacinação/história , Vacinação/legislação & jurisprudência , Abastecimento de Água/história
15.
Viruses ; 13(7)2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372534

RESUMO

(1) Background: Hemorrhagic diseases in white-tailed deer (Odocoileus virginianus) are caused by orbiviruses and have significant economic impact on the deer ranching industry in the United States. Culicoides stellifer is a suspected vector of epizootic hemorrhagic disease virus (EHDV), with recent field evidence from Florida, but its natural history is poorly understood. Studying the distribution and abundance of C. stellifer across the landscape can inform our knowledge of how virus transmission can occur locally. We may then target vector management strategies in areas where viral transmission can occur. (2) Methods: Here, we used an occupancy modeling approach to estimate abundance of adult C. stellifer females at various physiological states to determine habitat preferences. We then mapped midge abundance during the orbiviral disease transmission period (May-October) in Florida. (3) Results: We found that overall, midge abundance was positively associated with sites in closer proximity to large-animal feeders. Additionally, midges generally preferred mixed bottomland hardwood and agricultural/sand/water habitats. Female C. stellifer with different physiological states preferred different habitats. (4) Conclusions: The differences in habitat preferences between midges across states indicate that disease risk for deer is heterogeneous across this landscape. This can inform how effective vector management strategies should be implemented.


Assuntos
Ceratopogonidae/patogenicidade , Ceratopogonidae/virologia , Infecções por Reoviridae/prevenção & controle , Animais , Ceratopogonidae/metabolismo , Cervos/virologia , Suscetibilidade a Doenças , Ecossistema , Florida , Vírus da Doença Hemorrágica Epizoótica/patogenicidade , Insetos Vetores/virologia , Modelos Teóricos , Orbivirus/metabolismo , Orbivirus/patogenicidade , Infecções por Reoviridae/veterinária , Doenças Transmitidas por Vetores/prevenção & controle
16.
Proc Biol Sci ; 288(1956): 20210881, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34375559

RESUMO

Food limitation is a universal stressor for wildlife populations and is increasingly exacerbated by human activities. Anthropogenic environmental change can significantly alter the availability and quality of food resources for reservoir hosts and impact host-pathogen interactions in the wild. The state of the host's nutritional reserves at the time of infection is a key factor influencing infection outcomes by altering host resistance. Combining experimental and model-based approaches, we investigate how an environmental stressor affects host resistance to West Nile virus (WNV). Using American robins (Turdus migratorius), a species considered a superspreader of WNV, we tested the effect of acute food deprivation immediately prior to infection on host viraemia. Here, we show that robins food deprived for 48 h prior to infection, developed higher virus titres and were infectious longer than robins fed normally. To gain an understanding about the epidemiological significance of food-stressed hosts, we developed an agent-based model that simulates transmission dynamics of WNV between an avian host and the mosquito vector. When simulating a nutritionally stressed host population, the mosquito infection rate rose significantly, reaching levels that represent an epidemiological risk. An understanding of the infection disease dynamics in wild populations is critical to predict and mitigate zoonotic disease outbreaks.


Assuntos
Culex , Culicidae , Aves Canoras , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Humanos , Insetos Vetores , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária
17.
J Med Entomol ; 58(5): 2006-2011, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34342359

RESUMO

Medical Entomology as a field is inherently global - thriving on international and interdisciplinary collaborations and affected dramatically by arthropod and pathogen invasions and introductions. This past year also will be remembered as the year in which the SARS-CoV-2 COVID-19 pandemic affected every part of our lives and professional activities and impacted (or changed, sometimes in good ways) our ability to collaborate and detect or respond to invasions. This incredible year is the backdrop for the 2020 Highlights in Medical Entomology. This article highlights the broad scope of approaches and disciplines represented in the 2020 published literature, ranging from sensory and chemical ecology, population genetics, impacts of human-mediated environmental change on vector ecology, life history and the evolution of vector behaviors, to the latest developments in vector surveillance and control.


Assuntos
Entomologia , Aedes , Animais , COVID-19/epidemiologia , Meio Ambiente , Humanos , Controle de Insetos , Insetos Vetores , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos
18.
Artigo em Inglês | MEDLINE | ID: mdl-34353512

RESUMO

The genera Phlebovirus transmitted by Diptera belonging to the Psychodidae family are a cause of self-limited febrile syndrome in the Mediterranean basin in summer and autumn. Toscana virus can also cause meningitis and meningoencephalitis. In Spain, Toscana, Granada, Naples, Sicily, Arbia and Arrabida-like viruses have been detected. The almost widespread distribution of Phlebotomus genus vectors, and especially Phlebotomus perniciosus, in which several of these viruses have been detected, makes it very likely that there will be regular human infections in our country, with this risk considered moderate for Toscana virus and low for the other ones, in areas with the highest vector activity. Most of the infections would be undiagnosed, while only Toscana virus would have a greater impact due to the potential severity of the illness.


Assuntos
Phlebovirus , Psychodidae , Vírus da Febre do Flebótomo Napolitano , Animais , Humanos , Insetos Vetores , Espanha/epidemiologia
19.
Pan Afr Med J ; 38: 410, 2021.
Artigo em Francês | MEDLINE | ID: mdl-34381554

RESUMO

Introduction: synanthropic flies are sometimes involved in the transmission of diarrheal diseases as mechanical vectors of pathogenic bacteria. The purpose of this study was to assess the diversity of synanthropic flies and to determine their potential involvement in the transmission of diarrheal diseases in the city of Maroua. Methods: fly catching sessions were carried out per season in 12 wards, in five different sites and in three moments of the day, corresponding to the different daily sunshine hours. Multiple keys for the identification of diptera and of microbiological analyzes in the laboratory were used to estimate the biodiversity and the portage of microorganisms by the synanthropic flies. We carried out an ecological and statistical analyses of collected data. Results: eight species of synanthropic flies belonging to four families were identified in the city of Maroua and the distribution of these species varied according to the seasons, sites and moment of the day (p<0.05). Musca domestica and Chrysomya putoria were the most numerous species detected in the sites where the activities of agri-food processing and livestock were intense, notably Hardé, Pont-vert, Doualaré, Kongola and Makabaye. Escherichia coli was more involved than Salmonella spp.in the transmission of diarrheal diseases and the portage of bacteria by synanthropic flies was abundance-dependent. Conclusion: the diversity of synanthropic flies varies as a function of anthropogenic activities, season of the year and moment of the day. These flies are important potential mechanical vectors of fecal pathogenic bacteria in Maroua.


Assuntos
Bactérias/isolamento & purificação , Diarreia/epidemiologia , Dípteros/microbiologia , Insetos Vetores , Animais , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/transmissão , Camarões/epidemiologia , Diarreia/microbiologia , Humanos
20.
Biomed Environ Sci ; 34(7): 581-586, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34353424

RESUMO

Pathogens like bacteria and protozoa, which affect human and animal health worldwide, can be transmitted by vectors like ticks. To investigate the epidemiology and genetic diversity of bacteria and protozoans carried by ticks in Chengmai county of Hainan province, China, 285 adult hard ticks belonging to two species [ Rhipicephalus sanguineus ( sensu lato): 183, 64.21% and Rhipicephalus microplus: 102, 35.79%] from dogs, cattle, and goats were collected. Microbial families were identified in these ticks by amplifying the 18S rRNA, 16S rRNA ( rrs), citrate synthase ( gltA), and heat shock protein ( groEL) genes. Our data revealed the presence of four recognized species and two Candidatus spp. of Anaplasmataceae and Coxiellaceae. In sum, these data reveal an extensive diversity of Anaplasmataceae bacteria, Coxiellaceae bacteria, Babesiidae, and Hepatozoidae in ticks from Hainan Island, highlighting the need to understand the tick-borne pathogen infection in local animals and humans.


Assuntos
Anaplasmataceae/genética , Coccídios/genética , Coxiellaceae/genética , Insetos Vetores/microbiologia , Ixodidae/microbiologia , Piroplásmios/genética , Anaplasmataceae/isolamento & purificação , Animais , Chaperonina 60/genética , China , Citrato (si)-Sintase/genética , Coccídios/isolamento & purificação , Coxiellaceae/isolamento & purificação , Ilhas , Filogenia , Piroplásmios/isolamento & purificação , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética
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