scholarly journals A new malaria vector in Africa: Predicting the expansion range of Anopheles stephensi and identifying the urban populations at risk

2020 ◽  
Vol 117 (40) ◽  
pp. 24900-24908 ◽  
Author(s):  
M. E. Sinka ◽  
S. Pironon ◽  
N. C. Massey ◽  
J. Longbottom ◽  
J. Hemingway ◽  
...  
Keyword(s):  
Anopheles Stephensi ◽  
Close Association ◽  
Mosquito Species ◽  
Full Range ◽  
Spatial Models ◽  
Urban Environments ◽  
World Health ◽  
Horn Of Africa ◽  
Populations At Risk ◽  
Health Organization

In 2012, an unusual outbreak of urban malaria was reported from Djibouti City in the Horn of Africa and increasingly severe outbreaks have been reported annually ever since. Subsequent investigations discovered the presence of an Asian mosquito species; Anopheles stephensi, a species known to thrive in urban environments. Since that first report, An. stephensi has been identified in Ethiopia and Sudan, and this worrying development has prompted the World Health Organization (WHO) to publish a vector alert calling for active mosquito surveillance in the region. Using an up-to-date database of published locational records for An. stephensi across its full range (Asia, Arabian Peninsula, Horn of Africa) and a set of spatial models that identify the environmental conditions that characterize a species’ preferred habitat, we provide evidence-based maps predicting the possible locations across Africa where An. stephensi could establish if allowed to spread unchecked. Unsurprisingly, due to this species’ close association with man-made habitats, our maps predict a high probability of presence within many urban cities across Africa where our estimates suggest that over 126 million people reside. Our results strongly support the WHO’s call for surveillance and targeted vector control and provide a basis for the prioritization of surveillance.

scholarly journals Ecology of Malaria Vectors in an Endemic Area, Southeast of Iran

2021 ◽  
Author(s):  
Hamideh Edalat ◽  
Mehran Mahmoudi ◽  
Mohammad Mehdi Sedaghat ◽  
; Seyed Hassan Moosa-Kazemi ◽  
Sedigheh Kheirandish
Keyword(s):  
Anopheles Stephensi ◽  
Mosquito Species ◽  
Control Program ◽  
World Health ◽  
Malaria Vectors ◽  
Anopheles Mosquitoes ◽  
Larval Stages ◽  
Anopheles Fluviatilis ◽  
Vector Control Program ◽  
Health Organization

Background: Malaria has long been regarded as one of the most important public health issues in Iran. Although the country is now in the elimination phase, some endemic foci of malaria are still present in the southeastern areas of the country. In some endemic foci, there are no data on the malaria vectors. To fill this gap, the present study was designed to provide basic entomological data on malaria vectors in the southeastern areas of Iran. Methods: Adult and larval stages of Anopheles mosquitoes were collected by using different catch methods. Resistance of the main malaria vector in the study area to selected insecticides was evaluated using diagnostic doses advised by the World Health Organization in 2013–2014. Results: A total of 3288 larvae and 1055 adult Anopheles mosquitoes were collected, and identified as: Anopheles stephensi (32.1%), Anopheles culicifacies s.l. (23.4%), Anopheles dthali (23.2%), Anopheles superpictus s.l. (12.7%), and Anopheles fluviatilis s.l. (8.6%). Anopheles stephensi was the most predominant mosquito species collected indoors at the study area, with two peaks of activity in May and November. This species was found to be resistant to DDT 4%, tolerant to malathion 5% and susceptible to other tested insecticides. Conclusion: All the five malaria vectors endemic to the south of Iran were collected and identified in the study area. Our findings on the ecology and resting/feeding habitats of these malaria vectors provide information useful for planning vector control program in this malarious area.

Insecticide Resistance in Anopheles stephensi in Somali Region, Eastern Ethiopia

2020 ◽  
Author(s):  
Solomon Yared ◽  
Araya Gebressielasie ◽  
Lambodhar Damodaran ◽  
Victoria Bonnell ◽  
Karen Lopez ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Anopheles Stephensi ◽  
Mortality Rates ◽  
Resistance Mechanisms ◽  
World Health ◽  
Malaria Vectors ◽  
Eastern Ethiopia ◽  
Pyrethroid Insecticides ◽  
Pirimiphos Methyl ◽  
Health Organization

Abstract Background: The movement of malaria vectors into new areas is a growing concern in the efforts to control malaria. The recent report of Anopheles stephensi in eastern Ethiopia has raised the necessity to understand the insecticide resistance status of the vector in the region to better inform vector-based interventions. The aim of this study was to evaluate insecticide resistance in An. stephensi in eastern Ethiopia using two approaches: 1) World Health Organization (WHO) bioassay tests in An. stephensi and 2) genetic analysis of insecticide resistance genes in An. stephensi in eastern Ethiopia. Methods: Mosquito larvae and pupae were collected from Kebridehar. Insecticide susceptibility of An. stephensi was tested with malathion 5%, bendiocarb 0.1%, propoxur 0.1%, deltamethrin 0.05%, permethrin 0.75%, Pirimiphos-methyl 0.25% and DDT 4%, according to WHO standard protocols. Results: All An. stephensi samples were resistant to carbamates, with mortality rates 23% and 21% for bendiocarb and propoxur, respectively. Adult An. stephensi was also resistant to pyrethroid insecticides with mortality rates 67% for deltamethrin and 53% for permethrin. Resistance to DDT and malathion was detected in An. stephensi with mortality rates of 32% as well as An. stephensi was resistance to pirimiphos-methyl with mortality rates 14%. Analysis of the voltage gate sodium channel gene (vgsc) revealed the absence of kdr L1014 mutations. Conclusion: Overall, these findings support that An. stephensi is resistant to several classes of insecticides, most notably pyrethroids. However, the absence of the kdr L1014 gene may suggest non-target site resistance mechanisms. Continuous insecticide resistance monitoring should be carried out in the region to confirm the documented resistance and exploring mechanisms conferring resistance in An. stephensi in Ethiopia.

A global perspective on suicides and suicide attempts

2021 ◽  
pp. 93-98
Author(s):  
Elise Paul
Keyword(s):  
Suicide Attempt ◽  
Suicide Attempts ◽  
Global Perspective ◽  
World Health ◽  
Populations At Risk ◽  
Increased Risk ◽  
World Mental Health Survey ◽  
The World ◽  
Health Organization ◽  
Ongoing Monitoring

Specific populations at risk for suicide differ considerably according to region, country, sex, age, and the most common suicide methods used, highlighting the need for ongoing systematic surveillance to inform prevention efforts. The magnitude of the problem is not limited to suicide deaths. It is estimated that for every suicide, there are 20 more persons who have made an attempt. Individuals who have made a suicide attempt are at increased risk for dying by suicide. This chapter explores differences in the suicide and suicide attempt rates in the general population on different continents, by examining data from the World Health Organization (WHO) Global Health Estimates and the World Mental Health Survey Initiative. Differences across contexts in suicidal behaviours and the need for ongoing monitoring are emphasized.

The healthy settings approach: Healthy Cities and environmental health indicators

2018 ◽  
pp. 264-270
Author(s):  
Evelyne de Leeuw ◽  
Premila Webster
Keyword(s):  
Urban Health ◽  
Health Indicators ◽  
Evidence Base ◽  
Urban Environments ◽  
World Health ◽  
Healthy Cities ◽  
The World ◽  
Global Movement ◽  
Settings Approach ◽  
Health Organization

‘Healthy Cities’ is a global movement in urban health that grew from a Canadian initiative in the mid-1980s to a World Health Organization programme. Healthy Cities are characterized by a strong commitment to values such as sustainability, solidarity, justice, and participation embedded in a vision that embraces ecological and community perspectives. The movement comes in different manifestations around the world; this chapter focuses mostly on the European evidence base and discusses efforts that have been made over three decades to establish validated sets of indicators to measure and assess urban health and Healthy Cities. True to the nature of the movement, indicators are both socioecological and biomedical, qualitative, and quantitative. This presents challenges to validity and applicability across urban environments.

scholarly journals Noise and Air Pollution Related to Health in Urban Environments

Proceedings ◽  
2018 ◽  
Vol 2 (20) ◽  
pp. 1311 ◽  
Author(s):  
David Montes-González ◽  
Rosendo Vílchez-Gómez ◽  
Juan Miguel Barrigón-Morillas ◽  
Pedro Atanasio-Moraga ◽  
Guillermo Rey-Gozalo ◽  
...  
Keyword(s):  
Air Pollution ◽  
Road Traffic ◽  
Urban Environments ◽  
World Health ◽  
Sound Levels ◽  
European Environmental Agency ◽  
Environmental Health Risk ◽  
Health Organization ◽  
Relationship Of ◽  
The Relationship

Environmental noise is a pollutant considered by the World Health Organization (WHO) as a threat to public health due to its harmful effects on human health. In this regard, the European Environmental Agency (EEA) indicates that road traffic is the sound source that generates the greatest number of people exposed in Europe to sound levels above what is recommended by the European Noise Directive. In a similar way, the EEA also reports that air pollution is the most important environmental health risk in Europe, where road traffic is one of the main sources of emission of polluting gases. The relationship between both pollutants, leads to think about the development of common strategies. This paper presents a review on recent researches about the relationship of these two types of pollution in urban environments with different types of diseases.

scholarly journals Walkable Urban Environments: An Ergonomic Approach of Evaluation

2019 ◽  
Author(s):  
Letizia Appolloni ◽  
Alberto Giretti ◽  
Daniela D'Alessandro
Keyword(s):  
Bayesian Network ◽  
Urban Space ◽  
Urban Environments ◽  
World Health ◽  
Related Factors ◽  
Average Value ◽  
And Performance ◽  
Health Organization ◽  
The Relationship ◽  
Space Method

Background: The World Health Organization (WHO) stresses the need to create active environments, able to promote physical activity of people, according to their ability. Objective; This paper describes a new tool curried out to meaasure the relationship between the characteristics of urban space and its salutogenicity, intended as its ability to address population toward healthy lifestyles. Salutogenity has been read in terms of ergonomics of urban space. Method: The tool includes a set of 67 parameters, classified in needs, requirements and performance. It focuses on three requirements: usability, wellbeing and safety. The related performances are measured by a set of 29 indicators, divided in 5 categories (natural elements, built environment, mobility, urban furniture and perceived environment). To calibrate the tool, it was applied to 10 neighborhoods of Rieti city. To take into account the relationship between the variables, a causal network (Bayesian network) was applied. Findings: The average value of ergonomics of Rieti city, obtained applying the discrete bayesian model is 44.25%. Using the network, it is evident that by intervening on one node, the information requested expands to all the other nodes to which it is connected directly or indirectly, showing all the possible related factors. Conclusions: By using the tool and the discrete bayesian network it was possible to focus on the realities requiring analysis and to indicate the areas where the first interventions would be useful to increase the value of the analyzed nodes and, consequently, to improve the urban salutogenicity.

scholarly journals Genome Features of Asaia sp. W12 Isolated from the Mosquito Anopheles stephensi Reveal Symbiotic Traits

Genes ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 752
Author(s):  
Shicheng Chen ◽  
Ting Yu ◽  
Nicolas Terrapon ◽  
Bernard Henrissat ◽  
Edward D. Walker
Keyword(s):  
Molecular Mechanisms ◽  
Anopheles Stephensi ◽  
Environmental Changes ◽  
Plant Biomass ◽  
Close Association ◽  
Mosquito Species ◽  
Regulatory Protein ◽  
Terminal Oxidases ◽  
Multiple Organs ◽  
Insect Gut

Asaia bacteria commonly comprise part of the microbiome of many mosquito species in the genera Anopheles and Aedes, including important vectors of infectious agents. Their close association with multiple organs and tissues of their mosquito hosts enhances the potential for paratransgenesis for the delivery of antimalaria or antivirus effectors. The molecular mechanisms involved in the interactions between Asaia and mosquito hosts, as well as Asaia and other bacterial members of the mosquito microbiome, remain underexplored. Here, we determined the genome sequence of Asaia strain W12 isolated from Anopheles stephensi mosquitoes, compared it to other Asaia species associated with plants or insects, and investigated the properties of the bacteria relevant to their symbiosis with mosquitoes. The assembled genome of strain W12 had a size of 3.94 MB, the largest among Asaia spp. studied so far. At least 3585 coding sequences were predicted. Insect-associated Asaia carried more glycoside hydrolase (GH)-encoding genes than those isolated from plants, showing their high plant biomass-degrading capacity in the insect gut. W12 had the most predicted regulatory protein components comparatively among the selected Asaia, indicating its capacity to adapt to frequent environmental changes in the mosquito gut. Two complete operons encoding cytochrome bo3-type ubiquinol terminal oxidases (cyoABCD-1 and cyoABCD-2) were found in most Asaia genomes, possibly offering alternative terminal oxidases and allowing the flexible transition of respiratory pathways. Genes involved in the production of 2,3-butandiol and inositol have been found in Asaia sp. W12, possibly contributing to biofilm formation and stress tolerance.

scholarly journals Discriminating Lethal Concentrations for Transfluthrin, a Volatile Pyrethroid Compound for Mosquito Control in Thailand

2019 ◽  
Vol 35 (4) ◽  
pp. 258-266 ◽  
Author(s):  
Chutipong Sukkanon ◽  
Michael J. Bangs ◽  
Jirod Nararak ◽  
Jeffrey Hii ◽  
Theeraphap Chareonviriyaphap
Keyword(s):  
Mosquito Control ◽  
Mosquito Species ◽  
World Health ◽  
Testing System ◽  
Test Field ◽  
Complex Species ◽  
Control Programs ◽  
High Vapor ◽  
Health Organization ◽  
Routine Assessment

ABSTRACT Pyrethroids are commonly used to control malaria and dengue vectors in Thailand. The lack of specific lethal discriminating concentrations (DCs) for specific mosquito species has possibly compromised more accurate assessments of physiological susceptibility to various chemicals over time. Previous studies have established DCs of various residual pyrethroids against specific mosquitoes in Thailand. However, DCs for transfluthrin (TFT), a highly volatile pyrethroid compound, against mosquito vectors in Thailand has been lacking. The aim of this study was to determine the DCs and susceptibility baselines of TFT against pyrethroid-susceptible laboratory strains of Aedes aegypti, Anopheles minimus, and An. dirus using the World Health Organization adult susceptibility tube method. Final DCs of TFT of each species were determined based on doubling the 99% lethal concentration at the following percentages: Ae. aegypti (0.06824%), An. minimus (0.06382%), and An. dirus (0.01508%). Subsequently, the respective TFT DCs were used to test field-collected populations of Ae. aegypti, An. harrisoni (Minimus Complex species), and An. dirus. Anopheles harrisoni and An. dirus were found completely susceptible (100% mortality), whereas Ae. aegypti from Nonthaburi Province was resistant to TFT. The suitability of the testing system and procedures is discussed. Routine assessment of insecticide susceptibility should include pyrethroids with high-vapor-pressure characteristics for informing control programs and consumers of product and chemical effectiveness.

scholarly journals Genome Features of Asaia sp. W12 Isolated from the Mosquito Anopheles stephensi Reveal Symbiotic Traits

2021 ◽  
Author(s):  
Shicheng Chen ◽  
Ting Yu ◽  
Nicolas Terrapon ◽  
Bernard Henrissat ◽  
Edward Walker
Keyword(s):  
Molecular Mechanisms ◽  
Anopheles Stephensi ◽  
Environmental Changes ◽  
Close Association ◽  
Mosquito Species ◽  
Regulatory Protein ◽  
Terminal Oxidases ◽  
Cytochrome Bo3 ◽  
Multiple Organs ◽  
Protein Components

Asaia bacteria commonly comprise part of the microbiome of many mosquito species in the genera Anopheles and Aedes, including important vectors of infectious agents. Their close association with multiple organs and tissues of their mosquito hosts enhances the potential for paratransgenesis for delivery of anti-malaria or anti-virus effectors. The molecular mechanisms involved in the interactions between Asaia and mosquito hosts, as well as Asaia and other bacterial members of the mosquito microbiome, remained unexplored. Here, we determined the genome sequence of the strain W12 isolated from Anopheles stephensi mosquitoes, compared them to other Asaia species associated with plants or insects, and investigated some properties of the bacteria relevant to their symbiosis with host mosquitoes. The assembled genome of strain W12 has a size of 3.94 MB, which is the largest among Asaia spp studied so far. At least 3,585 coding sequences were predicted. The insect-associated Asaia including strain W12 carried more glycoside hydrolase (GH) encoding genes (31 per genome) than those isolated from plants (22 per genome). W12 had the most predicted regulatory protein components (213) among the selected Asaia (ranging from 131 to 211), indicating its great capability to adapt to frequent environmental changes in the mosquito gut. Two complete operons encoding cytochrome bo3-type ubiquinol terminal oxidases (cyoABCD-1 and cyoABCD-2) were found in most of Asaia genomes, which possibly offer alternative terminal oxidases and allow the flexible transition of respiratory pathways. Genes involved in the production of acetoin and 2,3-butandiol have been identified in Asaia sp. W12.

scholarly journals Predicting intensities of Zika infection and microcephaly using transmission intensities of other arboviruses

2016 ◽  
Author(s):  
Isabel Rodriguez-Barraquer ◽  
Henrik Salje ◽  
Justin Lessler ◽  
Derek AT Cummings
Keyword(s):  
Zika Virus ◽  
Strong Correlation ◽  
Mosquito Species ◽  
World Health ◽  
Detailed Knowledge ◽  
Crude Incidence ◽  
Force Of Infection ◽  
Dengue Transmission ◽  
Health Organization ◽  
Virus Emergence

The World Health Organization has declared Zika Virus a Public Health Emergency of International Concern due to the virus' emergence in multiple countries globally and the possible association of Zika virus with microcephaly and neurological disorders. There is a clear need to identify risk factors associated with Zika infection and microcephaly in order to target surveillance, testing and intervention efforts. Here, we show that there is a strong correlation between the incidence of Zika in Colombian departments and the force of infection (but not the crude incidence) of dengue, a virus transmitted by the same mosquito species, Aedes aegypti (R2 = 0.41, p<0.001). Furthermore, we show that there is also a strong correlation between the incidence of microcephaly in Brazilian states and the force of infection of dengue (R2 = 0.36, p<0.001). Because dengue, Zika and Chikungunya are transmitted by the same vector, these associations provide further support to the supposition that Zika virus infection during pregnancy causes microcephaly. In addition, they provide an opportunity to project the expected incidence of microcephaly in multiple dengue endemic locations across Colombia and the American continent. Detailed knowledge of dengue transmission should be use to target efforts against Zika and other flaviviruses.

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