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A dityrosine network mediated by dual oxidase and peroxidase influences the persistence of Lyme disease pathogens within the vector.

Ixodes scapularis ticks transmit a wide array of human and animal pathogens including Borrelia burgdorferi; however, how tick immune components influence the persistence of invading pathogens remains unknown. As originally demonstrated in Caenorhabditis elegans and later in Anopheles gambiae, we show here that an acellular gut barrier, resulting from the tyrosine cross-linking of the extracellular matrix, also exists in I. scapularis ticks. This dityrosine network (DTN) is dependent upon a dual oxidase (Duox), which is a member of the NADPH oxidase family. The Ixodes genome encodes for a singl…

Amazonian plant natural products: perspectives for discovery of new antimalarial drug leads.

Plasmodium falciparum and P. vivax malaria parasites are now resistant, or showing signs of resistance, to most drugs used in therapy. Novel chemical entities that exhibit new mechanisms of antiplasmodial action are needed. New antimalarials that block transmission of Plasmodium spp. from humans to Anopheles mosquito vectors are key to malaria eradication efforts. Although P. vivax causes a considerable number of malaria cases, its importance has for long been neglected. Vivax malaria can cause severe manifestations and death; hence there is a need for P. vivax-directed research. Plants used i…

Potential for mosquitoes (Diptera: Culicidae) from Florida to transmit Rift Valley fever virus.

We evaluated Aedes atlanticus Dyar and Knab, Aedes infirmatus Dyar and Knab, Aedes vexans (Meigen), Anopheles crucians Wiedemann, Coquillettidia perturbans (Walker), Culex nigripalpus Theobald, Mansonia dyari Belkin, Heinemann, and Page, and Psorophora ferox (Von Humboldt) from Florida to determine which of these species should be targeted for control should Rift Valley fever virus (RVFV) be detected in North America. Female mosquitoes that had fed on adult hamsters inoculated with RVFV were incubated for 7-21 d at 26 degrees C, then allowed to refeed on susceptible hamsters, and tested to det…

Monitoring of malaria, Japanese encephalitis and filariasis vectors.

BACKGROUND: Vector monitoring in military stations would help in protecting the armed forces from vector borne diseases such as malaria, Japanese encephalitis and filariasis. METHODS: Adult mosquitoes were collected from four villages around a military station in India using light traps and the species composition was estimated. Insecticide susceptibility of disease vectors against DDT, deltamethrin and permethrin was established using WHO kits. RESULTS: The known malaria vectors constituted 4.9% of the total mosquito collections and Anopheles philippinensis/nivipes (2.05%) was the most abun…

Mosquito-borne illnesses in travelers: a review of risk and prevention.

In 2008, residents of the United States made 12 million visits to developing countries in Asia, South America, Central America, Oceania, the Middle East, and Africa. Due to the presence of Anopheles, Aedes, and Culex mosquitoes, travel to these destinations poses a risk for diseases such as malaria, yellow fever, and Japanese encephalitis that cause significant morbidity and mortality. To gain a better understanding of the major emerging and established travel-related infectious diseases transmitted principally by mosquitoes and the measures for their prevention in U.S. residents who travel to…

LYMFASIM, a simulation model for predicting the impact of lymphatic filariasis control: quantification for African villages.

LYMFASIM is a simulation model for lymphatic filariasis transmission and control. We quantified its parameters to simulate Wuchereria bancrofti transmission by Anopheles mosquitoes in African villages, using a wide variety of reported data. The developed model captures the general epidemiological patterns, but also the differences between communities. It was calibrated to represent the relationship between mosquito biting rate and the prevalence of microfilariae (mf) in the human population, the age-pattern in mf prevalence, and the relation between mf prevalence and geometric mean mf intensit…

Natural vectors of dirofilariasis in rural and urban areas of the Tuscan region, central Italy.

Entomological investigations by means of dog- and human-baited traps were carried out in summers 2000-2002 in urban and rural areas of the T … cating their possible role as an intermediate host, but filarial DNA was found only in Cx. pipiens, Anopheles maculipennis s.l. (Meigen), and Coquillettidia richiardii (Ficalbi). In rural environments, the DNA evidence indicated the presence of infective larvae of Dirofilaria immitis, whereas in urban areas, infective larvae of Dirofilaria repens were prese …

Molecular characterization of insulin-like peptides in the yellow fever mosquito, Aedes aegypti: expression, cellular localization, and phylogeny.

Insulin-like peptides are key regulators of metabolism, reproduction, and senescence in higher eukaryotic organisms. Here we present the ide … enetic relationship of ILPs from three dipteran species, Ae. aegypti, the African malaria mosquito (Anopheles gambiae), and Drosophila melanogaster is presented as a step towards understanding the structural and functional diversity of insect ILPs.

Methylmercury in mosquitoes related to atmospheric mercury deposition and contamination.

A connection between loadings of inorganic Hg, especially from the atmosphere, and accumulation of methylmercury (MeHg) in aquatic biota has … g mosquito species at six sites in northwest Florida (Ochlerotatus atlanticus < Culex nigripalpus < Anopheles crucians); this may be related to differences in biogeochemical characteristics of the aquatic habitat that affect dietary accumulation of MeHg during the larval stage. Mosquito MeHg was related positively to wet atmospheric Hg deposition among loca …

Сезонная динамика четырех потенциальных векторных видов Западного Нила в северо-центральном Техасе.

В период с апреля по сентябрь 2002 года было проведено демографическое обследование видов комаров, происходящих в прибрежном коридоре &lt; &lt; Рэй Робертс Грин ремень &gt; &gt; , используемом для общественного отдыха на Эльм-Форке реки Троица, графство Дентон, TX. Программное обеспечение геоинформационной системы использовалось для создания стратифицированной случайной выборки на основе параметров среды обитания. Москиты собирались с помощью световых ловушек, гравичных ловушек и ящиков для отдыха. В ходе этого исследования было собрано в общей сложности 29 видов, относящихся к следующим роду:

Совпадение в аннотации оригинала
A population survey was conducted from April through September 2002 on mosquito species occurring on the Ray Roberts Greenbelt, a riparian c … es. A total of 29 species was collected during this study belonging to the following genera: Aedes, Anopheles, Coquillettidia, Culex, Mansonia, Ochlerotatus, Orthopodomyia, Psorophora, and Uranotaenia. The four most common species collected during this study were Aedes vexans, Culex erraticus, Culex salinarius, and Psorophora columbiae. West Nile virus (WNV …

The epidemiology of malaria in Rondonia (Western Amazon region, Brazil): study of a riverine population.

We report on a longitudinal study concerning the incidence of malaria in a riverine population (Portuchuelo) settled on the riverbanks of Ri … igrants or eventual settlers at their vicinity. To date, the opposite view has been generally held. Anopheles darlingi, the main vector species in the area, is essentially sylvatic, which contributes to make the control of malaria highly problematic. The only hopes for control rest on permanent surveillance and the prompt treatment of patients, which are al …

Conforming strategies of public health campaigns to disease specificity and national contexts: Rockefeller Foundation's early campaigns against hookworm and malaria in Brazil.

The early experience of Rockefeller Foundation in Brazil, starting in 1915, reflected the idea of extending learned experience in Southern U … ast dependency on local social and political dynamics, as in the exemplar case of Frederick Soper's Anopheles gambiae eradication campaign (1938-1942).

Lack of malaria parasite transmission between apes and humans in Gabon.

The International Center for Medical Research (CIRMF) is located in an area highly endemic for malaria in southeastern Gabon, where humans and apes (gorillas and chimpanzees) are living in the same geographic area. The presence of the CIRMF primate center housing apes (59 chimpanzees and nine gorillas in 1994) within the city of Franceville provided an opportunity to investigate the capability of cross-transmission of malaria species from humans to apes. The main vector of human malaria, Anopheles gambiae, was found in the primate center and in a nearby populated area of Franceville. Despite h…

Knowledge, beliefs, and practices in relation to malaria transmission and vector control in Guatemala.

As part of an effort to involve community members in malaria control activities, we studied knowledge, beliefs, and practices of residents of both the Pacific coastal plain and northeastern Guatemala related to malaria transmission and Anopheles albimanus control. Most residents recognized the role of mosquitoes in malaria transmission, but few knew how mosquitoes acquired their infections or understood the risk of having an untreated person in their midst. If this were more widely known, residents might put greater pressure on infected patients to seek timely and appropriate antimalarial trea…

[Mosquito nets impregnated against malaria in Zaire].

On the Bateké plateau 60 km east of Kinshasa, Zaïre, where malaria is stable, three villages have been selected for a trial of malaria control using bednets impregnated with deltamethrin at 25 mg per square meter from February to November 1991. One village (3,000 inhabitants) has been provided 800 impregnated bednets and an other one (2,900 inhabitants) kept 800 non impregnated bednets. The third village (900 inhabitants) served as a control and has remained without nets. Anopheles gambiae was the main and nearly exclusive vector of malaria. Its biting density was reduced by 94% in the village…

Integrating 3D video tracking with the standard WHO tunnel assay: a proof-of-concept to support improving insecticide-treated nets for mosquito control.

The World Health Organization (WHO) tunnel test is a standardised laboratory assay used to characterise the biological availability and potency of active ingredients on the surface of an insecticide-treated bed net (ITN) against host-seeking mosquitoes. However, the assay provides only endpoint measurements-the proportions of mosquitoes killed and blood-fed - and therefore offers no insight into how mosquitoes interact with the ITN. Therefore, complementary behavioural data would be highly valuable, for example to reveal the extent to which mosquitoes engage with the net, thereby helping to ex

Reframing vector control: land use and climate shape malaria risk in Amazonian communities.

BACKGROUND: Malaria remains a major public health challenge in the Brazilian Amazon, where ecological heterogeneity and socio-economic vulnerability hinder the effectiveness of vector elimination. The primary vector, Nyssorhynchus darlingi, shows substantial spatiotemporal variation influenced by land-use changes and local microclimates. OBJECTIVES: Investigate how land cover and microclimatic factors affect Ny. darlingi human biting rate (HBR) across different Amazonian ecoregions. METHODS: HBR was measured through human landing catches at 70 sites in four ecoregions, with simultaneous temp

A spatial multiscale mathematical model of Plasmodium vivax transmission.

The epidemiological behavior of Plasmodium vivax malaria occurs across spatial scales including within-host, population, and metapopulation levels. On the within-host scale, P. vivax sporozoites inoculated in a host may form latent hypnozoites, the activation of which drives secondary infections and accounts for a large proportion of P. vivax illness; on the metapopulation level, the coupled human-vector dynamics characteristic of the population level are further complicated by the migration of human populations across patches with different malaria forces of (re-)infection. To explore the int

First report on larvicidal potential of zinc sulfide aqua nanoparticles against Aedes aegypti (Linnaeus).

BACKGROUND & OBJECTIVES: Mosquitoes are considered to be the deadliest arthropod-vectors, which cause millions of human deaths globally. Presently, nanotechnology in the field of insect pest management is being explored. The current study deals with the synthesis of zinc sulfide nanoparticles (ZnS NPs) in aqueous medium and their larvicidal efficacy against Ae. aegypti. METHODS: Aqueous zinc sulfide nanoparticles were synthesized by mixing equal quantities of zinc acetate and zinc sulfide solutions by using sonochemical irradiation method. The synthesized NPs were characterized by Transmissio

Impact of Environmental Modifications on the Ecology, Epidemiology, and Pathogenesis of Plasmodium falciparum and Plasmodium vivax Malaria in East Africa.

Food insecurity, recurrent famine, and poverty threaten the health of millions of African residents. Construction of dams and rural irrigation schemes is key to solving these problems. The sub-Saharan Africa International Center of Excellence for Malaria Research addresses major knowledge gaps and challenges in Plasmodium falciparum and Plasmodium vivax malaria control and elimination in malaria-endemic areas of Kenya and Ethiopia where major investments in water resource development are taking place. This article highlights progress of the International Center of Excellence for Malaria Resear