Urbanization creates diverse aquatic habitats for immature mosquitoes in urban areas

Abstract Global increases in temperatures and urbanization are impacting the epidemiology of mosquito-borne diseases. Urbanization processes create suitable habitats for vector mosquitoes in which there are a reduced number of predators, and human hosts are widely available. We hypothesize that mosquito vector species, especially Aedes aegypti, are locally concentrated primarily in those specific habitats at the neighborhood levels that provide suitable conditions and environmental resources needed for mosquito survival. Determining how mosquito vector species composition and abundance depend on environmental resources across habitats addresses where different types of vector control need to be applied. Therefore, our goal was to analyze and identify the most productive aquatic habitats for mosquitoes in Miami-Dade County, Florida. Immature mosquito surveys were conducted throughout Miami-Dade County from April 2018 to June 2019, totaling 2,488 inspections. Mosquitoes were collected in 76 different types of aquatic habitats scattered throughout 141 neighborhoods located in the urbanized areas of Miami-Dade County. A total of 44,599 immature mosquitoes were collected and Ae. aegypti was the most common and abundant species, comprising 43% of all specimens collected. Aedes aegypti was primarily found in buckets, bromeliads, and flower pots, concentrated in specific neighborhoods. Our results showed that aquatic habitats created by anthropogenic land-use modifications (e.g., ornamental bromeliads, buckets, etc.) were positively correlated with the abundance of Ae. aegypti. This study serves to identify how vector mosquitoes utilize the resources available in urban environments and to determine the exact role of these specific urban features in supporting populations of vector mosquito species. Ultimately, the identification of modifiable urban features will allow the development of targeted mosquito control strategies optimized to preventatively control vector mosquitoes in urban areas.

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Urbanization favors the proliferation of Aedes aegypti and Culex quinquefasciatus in urban areas of Miami-Dade County, Florida

Scientific Reports ◽

10.1038/s41598-021-02061-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

André B. B. Wilke ◽

Chalmers Vasquez ◽

Augusto Carvajal ◽

Maday Moreno ◽

Douglas O. Fuller ◽

...

Keyword(s):

Community Composition ◽

Rural Areas ◽

Urban Areas ◽

Mosquito Control ◽

Mosquito Species ◽

Pathogen Transmission ◽

Dade County ◽

Mosquito Vector ◽

Remote Areas ◽

Anthropogenic Alterations

AbstractUrbanization processes are increasing globally. Anthropogenic alterations in the environment have profound effects on biodiversity. Decreased biodiversity due to biotic homogenization processes as a consequence of urbanization often result in increased levels of mosquito vector species and vector-borne pathogen transmission. Understanding how anthropogenic alterations in the environment will affect the abundance, richness, and composition of vector mosquito species is crucial for the implementation of effective and targeted mosquito control strategies. We hypothesized that anthropogenic alterations in the environment are responsible for increasing the abundance of mosquito species that are adapted to urban environments such as Aedesaegypti and Culexquinquefasciatus. Therefore, our objective was to survey mosquito relative abundance, richness, and community composition in Miami-Dade County, Florida, in areas with different levels of urbanization. We selected 24 areas, 16 remote areas comprised of natural and rural areas, and 8 urban areas comprised of residential and touristic areas in Miami-Dade County, Florida. Mosquitoes were collected weekly in each area for 24 h for 5 consecutive weeks from August to October 2020 using BG-Sentinel traps baited with dry ice. A total of 36,645 mosquitoes were collected, from which 34,048 were collected in the remote areas and 2,597 in the urban areas. Our results show a clear and well-defined pattern of abundance, richness, and community composition according to anthropogenic modifications in land use and land cover. The more urbanized a given area the fewer species were found and those were primary vectors of arboviruses, Ae.aegypti and Cx.quinquefasciatus.

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Effectiveness of adulticide and larvicide in controlling high densities of Aedes aegypti in urban environments

PLoS ONE ◽

10.1371/journal.pone.0246046 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0246046

Author(s):

André B. B. Wilke ◽

Chalmers Vasquez ◽

Augusto Carvajal ◽

Monica Ramirez ◽

Gabriel Cardenas ◽

...

Keyword(s):

Aedes Aegypti ◽

Relative Abundance ◽

Urban Areas ◽

Mosquito Control ◽

Urban Environments ◽

Baseline Survey ◽

Dade County ◽

Bacillus Thuringiensis Israelensis ◽

Breeding Habitats ◽

And Control

Current management and control of Aedes aegypti populations in urban areas are based on the spraying of insecticides. Here, we evaluated the effectiveness of spraying larvicide (Bacillus thuringiensis israelensis) using a truck-mounted Buffalo Turbine and adulticide (Deltamethrin) using a Grizzly ULV Sprayer in an urban area with high densities of Ae. aegypti and many cryptic and difficult to reach aquatic breeding habitats. Experiments were conducted in a tire shop located in Miami-Dade County, Florida with approximately 100,000 used airplane tires. Insecticide interventions were performed after a baseline survey consisting of 3 weeks of collections, followed by two insecticide interventions: (i) application of the adulticide followed by the application of larvicide on the subsequent week; and (ii) application of both adulticide and larvicide on two consecutive weeks. The first insecticide intervention resulted in a non-significant decrease in the relative abundance of Ae. aegypti. On the other hand, the second insecticide intervention significantly reduced the Ae. aegypti relative abundance (P < 0.002). Our results demonstrated that the combined insecticide interventions on two consecutive weeks significantly reduced the relative abundance of Ae. aegypti. This result indicated that the larvicide was successfully propelled reaching cryptical and difficult to reach aquatic habitats. However, even though the number of mosquitoes was greatly reduced, it was still greatly above the 10-mosquito threshold by trap night used by the Miami-Dade Mosquito Control Division to deploy an inspector to survey the area. Considering the lack of new and effective mosquito control tools, efficient and mobile insecticide propellers such as Buffalo Turbine can be of great help to manage mosquito populations in urban areas.

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Larval habitat diversity and mosquito species distribution along the coast of Kenya

Wellcome Open Research ◽

10.12688/wellcomeopenres.15550.1 ◽

2019 ◽

Vol 4 ◽

pp. 175 ◽

Cited By ~ 1

Author(s):

Miriam Karuitha ◽

Joel Bargul ◽

Joel Lutomiah ◽

Simon Muriu ◽

Joseph Nzovu ◽

...

Keyword(s):

Species Diversity ◽

Aedes Aegypti ◽

Urban Areas ◽

Mosquito Species ◽

Habitat Diversity ◽

Larval Habitat ◽

Control Measures ◽

Effective Control ◽

Aquatic Habitats ◽

Forested Areas

Background: Management of arboviruses relies heavily on vector control. Implementation and sustenance of effective control measures requires regular surveillance of mosquito occurrences, species abundance and distribution. The current study evaluated larval habitat diversity and productivity, mosquito species diversity and distribution in selected sites along the coast of Kenya. Methods: A cross-sectional survey of mosquito breeding habitats, species diversity and distribution was conducted in urban, peri-urban and forested ecological zones in Mombasa and Kilifi counties. Results: A total of 13,009 immature mosquitoes were collected from 17 diverse aquatic habitats along the coast of Kenya. Larval productivity differed significantly (F (16, 243) = 3.21, P < 0.0001) among the aquatic habitats, with tyre habitats recording the highest larval population. Culex pipiens (50.17%) and Aedes aegypti (38.73%) were the dominant mosquito species in urban areas, while Ae. vittatus (89%) was the dominant species in forested areas. In total, 4,735 adult mosquitoes belonging to 19 species were collected in Haller Park, Bamburi, Gede and Arabuko Sokoke forest. Urban areas supported higher densities of Ae. aegypti compared to peri-urban and forest areas, which, on the other hand, supported greater mosquito species diversity. Conclusions: High Ae. aegypti production in urban and peri-urban areas present a greater risk of arbovirus outbreaks. Targeting productive habitats of Aedes aegypti, such as discarded tyres, containers and poorly maintained drainage systems in urban areas and preventing human-vector contact in peri-urban and forested areas could have a significant impact on the prevalence of arboviruses along the coast of Kenya, forestalling the periodic outbreaks experienced in the region.

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A Simple PCR Assay for Discrimination of Dengue Vectors from Nsukka LGA, Nigeria

International Annals of Science ◽

10.21467/ias.10.1.67-77 ◽

2020 ◽

Vol 10 (1) ◽

pp. 67-77

Author(s):

Amos Watentena ◽

Ikem Chris Okoye ◽

Ikechukwu Eugene Onah ◽

Onwude Cosmas Ogbonnaya ◽

Emmanuel Ogudu

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Mosquito Species ◽

Public Health Problem ◽

Major Public Health Problem ◽

Mosquito Vector ◽

Aedes Mosquitoes ◽

Allele Specific ◽

Arboviral Diseases ◽

Dengue Vectors

Mosquitoes of Aedes species are vectors of several arboviral diseases which continue to be a major public health problem in Nigeria. This study among other things, morphologically identified Aedes mosquitoes collected from Nsukka LGA and used an allele specific PCR amplification for discrimination of dengue vectors. Larval sampling, BG-sentinel traps and modified human landing catches were used for mosquito sampling in two selected autonomous communities of Nsukka LGA (Nsukka and Obimo). A total of 124 Aedes mosquitoes consisting of five (5) different species were collected from April to June, 2019 in a cross-sectional study that covered 126 households, under 76 distinct geographical coordinates. Larvae was mainly collected from plastic containers 73% (n=224), metallic containers 14% (n=43), earthen pots 9% (n=29) and used car tyres 3% (n=9), reared to adult stage 69.35% (n=86), and all mosquitoes were identified using standard morphological keys. Five (5) Aedes mosquito species were captured; Aedes aegypti 83(66.94%), Aedes albopictus 33(26.61%), Aedes simpsoni (4.48%), Aedes luteocephalus (≤1%) and Aedes vittatus (≤1%). Nsukka autonomous community had higher species diversity than Obimo. Allele specific amplification confirmed dengue vectors, Aedes aegypti and Aedes albopictus species on a 2% agarose gel. Since the most recent re-emergence of arboviral diseases is closely associated with Aedes species, findings of this study, therefore, give further evidence about the presence of potential arboviral vectors in Nigeria and describe the role of a simple PCR in discriminating some. Further entomological studies should integrate PCR assays in mosquito vector surveillance.

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THE USE OF AGENTS BASED ON THE BACTERIUM BACILLUS THURINGIENSIS VAR. ISRAELENSIS FOR MOSQUITO CONTROL

Hygiene and Sanitation ◽

10.18821/0016-9900-2019-98-8-893-896 ◽

2019 ◽

Vol 98 (8) ◽

pp. 893-896

Author(s):

Svetlana A. Roslavtseva

Keyword(s):

Bacillus Thuringiensis ◽

Aedes Aegypti ◽

Synergistic Effect ◽

Mosquito Control ◽

Mosquito Species ◽

Bacillus Sphaericus ◽

Development Of Resistance ◽

Blood Sucking ◽

Low Concentrations ◽

Bacterium Bacillus

Mosquito control is necessary to improve the epidemic and, consequently, the sanitary and hygienic situation in human settlements. At the same time, the safest and more environmentally friendly way of controlling is not the fight against adult mosquitoes, but the treatment of reservoirs with microbiological larvicides based on entomopathogenic, aerobic, spore-forming, saprophytic bacteria Bacillus thuringiensis (de Barjac) (Bti). A new serotype of the bacterium B. thuringiensis was found in Israel in the Negev desert. This serotype being more active against larvae of blood-sucking and non-blood-sucking mosquitoes and midges than previously known serotypes, was named israelensis. Bti endotoxin is a typical insecticide with intestinal type of action for different mosquito species. For example, Bti H14 is highly insecticidal to the larvae of Aedes aegypti and Ae. albopictus at very low concentrations. The parasporal body (endotoxin crystal), a crystalline protein consisted of four main polypeptides and two minor polypeptides, possesses of a larvicidal action. Larvicidal activity is associated with a synergistic effect in a combination of four polypeptides. The possibility of development of resistance to products based on Bti and Bacillus sphaericus in populations of mosquitoes (Culicidae) was investigated. The use of domestic microbiological formulations based on Bti («Baktitsid», «Larviol-pasta», and «Antinat») was shown an eradication the larvae of bloodsucking mosquitoes and midges to be possible and rational, since they are not generated resistant populations of mosquitoes. This is confirmed by more than 30 years of the use of such formulations.

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Tumbuhan Obat: Pendekatan Alternatif dalam Pengendalian Nyamuk Aedes aegypti dan Virus Dengue Penyebab Demam Dengue

JURNAL BIOLOGI PAPUA ◽

10.31957/jbp.541 ◽

2018 ◽

Vol 4 (2) ◽

pp. 83-90

Author(s):

Ign Joko Suyono ◽

Aditya K. Karim

Keyword(s):

Medicinal Plant ◽

Aedes Aegypti ◽

Dengue Fever ◽

Mosquito Control ◽

Dengue Shock Syndrome ◽

Viral Disease ◽

Mosquito Vector ◽

Major Health ◽

Alternative Approach ◽

Control And Prevention

Dengue is the most important emerging tropical viral disease of humans in the world today. Aedes aegypti is a major mosquito vector responsible for transmitting many viral diseases and this mosquito that spreads major health problems like dengue fever. The resistance of Ae. aegypti to insecticides is already widespread and represents a serious problem for programmes aimed at the control and prevention of dengue in tropical countries. The search for compounds extracted from medicinal plant preparations as alternatives insecticide for mosquito control is in immediate need. Alternative approach for control Ae. aegypti dan virus dengue using the medicinal plant will be discussed in this paper.Key words: Medicinal plant, Aedes aegypti, dengue fever, dengue haemorragi fever, dengue shock syndrome

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Socio-Ecological Factors Associated with Dengue Risk and Aedes aegypti Presence in the Galápagos Islands, Ecuador

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16050682 ◽

2019 ◽

Vol 16 (5) ◽

pp. 682 ◽

Cited By ~ 5

Author(s):

Sadie Ryan ◽

Catherine Lippi ◽

Ryan Nightingale ◽

Gabriela Hamerlinck ◽

Mercy Borbor-Cordova ◽

...

Keyword(s):

Aedes Aegypti ◽

Mosquito Control ◽

Dengue Infection ◽

Galapagos Islands ◽

Mosquito Vector ◽

Housing Conditions ◽

Galápagos Islands ◽

Linear Regression Models ◽

Factors Associated ◽

Attitudes And Practices

Dengue fever is an emerging infectious disease in the Galápagos Islands of Ecuador, with the first cases reported in 2002 and subsequent periodic outbreaks. We report results of a 2014 pilot study conducted in Puerto Ayora (PA) on Santa Cruz Island, and Puerto Baquerizo Moreno (PB) on San Cristobal Island. To assess the socio-ecological risk factors associated with dengue and mosquito vector presence at the household level, we conducted 100 household surveys (50 on each island) in neighborhoods with prior reported dengue cases. Adult mosquitoes were collected inside and outside the home, larval indices were determined through container surveys, and heads of households were interviewed to determine demographics, self-reported prior dengue infections, housing conditions, and knowledge, attitudes, and practices regarding dengue. Multi-model selection methods were used to derive best-fit generalized linear regression models of prior dengue infection, and Aedes aegypti presence. We found that 24% of PB and 14% of PA respondents self-reported a prior dengue infection, and more PB homes than PA homes had Ae. aegypti. The top-ranked model for prior dengue infection included several factors related to human movement, household demographics, access to water quality issues, and dengue awareness. The top-ranked model for Ae. aegypti presence included housing conditions, mosquito control practices, and dengue risk perception. This is the first study of dengue risk and Ae. aegypti presence in the Galápagos Islands.

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RNA-seq analyses of blood-induced changes in gene expression in the mosquito vector species, Aedes aegypti

BMC Genomics ◽

10.1186/1471-2164-12-82 ◽

2011 ◽

Vol 12 (1) ◽

Cited By ~ 83

Author(s):

Mariangela Bonizzoni ◽

W Augustine Dunn ◽

Corey L Campbell ◽

Ken E Olson ◽

Michelle T Dimon ◽

...

Keyword(s):

Gene Expression ◽

Aedes Aegypti ◽

Mosquito Vector ◽

Rna Seq ◽

Vector Species ◽

Induced Changes

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Crowdsourcing for large-scale mosquito (Diptera: Culicidae) sampling

The Canadian Entomologist ◽

10.4039/tce.2014.27 ◽

2014 ◽

Vol 147 (1) ◽

pp. 118-123 ◽

Cited By ~ 5

Author(s):

Elin C. Maki ◽

Lee W. Cohnstaedt

Keyword(s):

Large Scale ◽

Mosquito Control ◽

Mosquito Species ◽

Local Level ◽

The United States ◽

Mosquito Vector ◽

Culex Tarsalis ◽

Aedes Vexans ◽

Control Programmes ◽

And Control

AbstractSampling a cosmopolitan mosquito (Diptera: Culicidae) species throughout its range is logistically challenging and extremely resource intensive. Mosquito control programmes and regional networks operate at the local level and often conduct sampling activities across much of North America. A method for large-scale sampling of two mosquito species using crowdsourcing to network with these local and regional programmes is described. A total of 961 mosquito vector and control districts, health departments, and individual collectors across the United States of America and Canada were contacted in 2011 and 2012 of which 9% positively responded by sending mosquitoes. In total, 1101 unique population samples of Aedes vexans (Meigen) and Culex tarsalis Coquillett were collected throughout their range in these two countries. Aedes vexans outgroup samples were also submitted from Europe and Asia. This is the largest crowd-sourced collection of samples to date.

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Spatial Distribution of Aedes aegypti Oviposition Temporal Patterns and Their Relationship with Environment and Dengue Incidence

Insects ◽

10.3390/insects12100919 ◽

2021 ◽

Vol 12 (10) ◽

pp. 919

Author(s):

Verónica Andreo ◽

Ximena Porcasi ◽

Claudio Guzman ◽

Laura Lopez ◽

Carlos M. Scavuzzo

Keyword(s):

Time Series ◽

Spatial Distribution ◽

Aedes Aegypti ◽

Urban Areas ◽

Mosquito Species ◽

Activity Patterns ◽

Positive Association ◽

Temporal Patterns ◽

Transmission Risk ◽

Machine Learning Classification

Aedes aegypti, the mosquito species transmitting dengue, zika, chikungunya and yellow fever viruses, is fully adapted to thrive in urban areas. The temporal activity of this mosquito, however, varies within urban areas which might imply different transmission risk. In this work, we hypothesize that temporal differences in mosquito activity patterns are determined by local environmental conditions. Hence, we explore the existence of groups of temporal patterns in weekly time series of Ae. aegypti ovitraps records (2017–2019) by means of time series clustering. Next, with the aim of predicting risk in places with no mosquito field data, we use machine learning classification tools to assess the association of temporal patterns with environmental variables derived from satellite imagery and predict temporal patterns over the city area to finally test the relationship with dengue incidence. We found three groups of temporal patterns that showed association with land cover diversity, variability in vegetation and humidity and, heterogeneity measured by texture indices estimated over buffer areas surrounding ovitraps. Dengue incidence on a neighborhood basis showed a weak but positive association with the percentage of pixels belonging to only one of the temporal patterns detected. The understanding of the spatial distribution of temporal patterns and their environmental determinants might then become highly relevant to guide the allocation of prevention and potential interventions. Further investigation is still needed though to incorporate other determinants not considered here.

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