A NEW LABORATORY COLONIZATION OF AEDES AEGYPTI AFTER REEMERGENCE AND UNSUCCESSFUL ERADICATION IN ST. AUGUSTINE, FLORIDA

Aedes mosquitoes harboring intracellular Wolbachia bacteria are being released in arbovirus and mosquito control programs. With releases taking place around the world, understanding the contribution of host variation to Wolbachia phenotype is crucial. We generated a Wolbachia transinfection ( w AlbB Q ) in Aedes aegypti and performed backcrossing to introduce the infection into Australian or Malaysian nuclear backgrounds. Whole Wolbachia genome sequencing shows that the w AlbB Q transinfection is near-identical to the reference w AlbB genome, suggesting few changes since the infection was first introduced to Ae. aegypti over 15 years ago. However, these sequences were distinct from other available w AlbB genome sequences, highlighting the potential diversity of w AlbB in natural Ae. albopictus populations. Phenotypic comparisons demonstrate effects of w AlbB infection on egg hatch and nuclear background on fecundity and body size, but no interactions between w AlbB infection and nuclear background for any trait. The w AlbB infection was stable at high temperatures and showed perfect maternal transmission and cytoplasmic incompatibility regardless of host background. Our results demonstrate the stability of w AlbB across host backgrounds and point to its long-term effectiveness for controlling arbovirus transmission and mosquito populations. Importance Wolbachia bacteria are being used to control the transmission of dengue and other arboviruses by mosquitoes. For Wolbachia release programs to be effective globally, Wolbachia infections must be stable across mosquito populations from different locations. In this study, we transferred Wolbachia (strain w AlbB) to Aedes aegypti mosquitoes with an Australian genotype and introduced the infection to Malaysian mosquitoes through backcrossing. We found that the phenotypic effects of Wolbachia are stable across both mosquito backgrounds. We sequenced the genome of w AlbB and found very few genetic changes despite spending over 15 years in a novel mosquito host. Our results suggest that the effects of Wolbachia infections are likely to remain stable across time and host genotype.

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A wAlbB Wolbachia transinfection displays stable phenotypic effects across divergent Aedes aegypti mosquito backgrounds

10.1101/2021.06.25.450002 ◽

2021 ◽

Author(s):

Perran A Ross ◽

Xinyue Gu ◽

Katie L Robinson ◽

Qiong Yang ◽

Ellen Cottingham ◽

...

Keyword(s):

Aedes Aegypti ◽

Cytoplasmic Incompatibility ◽

Mosquito Control ◽

Maternal Transmission ◽

Genome Sequences ◽

Egg Hatch ◽

Control Programs ◽

Nuclear Background ◽

The Stability

Aedes mosquitoes harboring intracellular Wolbachia bacteria are being released in arbovirus and mosquito control programs. With releases taking place around the world, understanding the contribution of host variation to Wolbachia phenotype is crucial. We generated a Wolbachia transinfection (wAlbBQ) in Aedes aegypti and performed backcrossing to introduce the infection into Australian or Malaysian nuclear backgrounds. Whole Wolbachia genome sequencing shows that the wAlbBQ transinfection is near-identical to the reference wAlbB genome, suggesting few changes since the infection was first introduced to Ae. aegypti over 15 years ago. However, these sequences were distinct from other available wAlbB genome sequences, highlighting the potential diversity of wAlbB in natural Ae. albopictus populations. Phenotypic comparisons demonstrate effects of wAlbB infection on egg hatch and nuclear background on fecundity and body size, but no interactions between wAlbB infection and nuclear background for any trait. The wAlbB infection was stable at high temperatures and showed perfect maternal transmission and cytoplasmic incompatibility regardless of host background. Our results demonstrate the stability of wAlbB across host backgrounds and point to its long-term effectiveness for controlling arbovirus transmission and mosquito populations.

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PENGENDALIAN VEKTOR NYAMUK AEDES AEGYPTI DI RUMAH SAKIT KOTA SURABAYA

The Indonesian Journal of Public Health ◽

10.20473/ijph.v13i1.2018.73-84 ◽

2019 ◽

Vol 13 (1) ◽

pp. 73

Author(s):

Ekalina Atikasari ◽

Lilis Sulistyorini

Keyword(s):

Aedes Aegypti ◽

Vector Control ◽

Environmental Health ◽

Disease Transmission ◽

Mosquito Control ◽

Secondary Data ◽

Mosquito Vector ◽

Human Contact ◽

The Republic ◽

And Control

Vector control is an approach using the basic principles of management and consideration of disease transmission and control. The purpose of vector control is to reduce vector breeding habitats, reduce vector density, inhibit disease transmission, reduce human contact with vectors so that vector-borne disease transmission can be controlled more rationally, effectively and efficiently. This study aims to analyze the effectiveness of Aedes aegypti mosquito control vector in a hospital in Surabaya. The Control carried out by the Hospital is to eradicate Aedes aegypti mosquitoes by installing Ovitrap, Thermal Fogging, Cold Fogging and Spraying. The type of analysis used is descriptive observational. Data collection was carried out in February of 2017 at K3 unit and Environmental Health of Surabaya Hospital. The data used are hospital pest and rodent control report, secondary data aboutnumber of mosquito, number of larvae and number of Aedes aegypti mosquito eggs obtained from unit of K3 and Environmental Health. The conclusions for the hospital are: (1) always report the Aedes aegypti mosquito vector routine every months; (2) eradicating mosquitoes in difficult places such as patient and dense populated areas; (3) based on Regulation of the Minister of Health of the Republic of Indonesia Number 374 / MENKES / PER / III / 2010 concerning Vector Control four of the six tools used in the Hospital have been used

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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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Studies on the Responses of the female Aëdes Mosquito

Bulletin of Entomological Research ◽

10.1017/s0007485300002893 ◽

1957 ◽

Vol 48 (4) ◽

pp. 783-793 ◽

Cited By ~ 17

Author(s):

L. Burgess ◽

A. W. A. Brown

Keyword(s):

Aqueous Solution ◽

Aedes Aegypti ◽

Water Vapour ◽

Filter Paper ◽

Whole Blood ◽

Paired Comparisons ◽

Ether Extract ◽

Aedes Mosquito ◽

Volatile Substances ◽

And Control

The responses of females of Aëdes aegypti (L.) to beef blood have been investigated. Paired comparisons were made of the numbers of mosquitos attracted to test and control materials.Vapours emanating from the heparinised blood were found to be significantly more attractive than water vapour in an olfactometer. When the blood vapour was passed through an aqueous solution of Ba(OH)2 this attractiveness disappeared.Exposure of heparinised blood on filter paper proved it to be two to four times as attractive as water or washed corpuscles suspended in saline. Plasma proved to be 4·7 times as attractive as water, indicating that the attraction of blood lies entirely in the plasma.Treatment of blood with BaCl2 and a vacuum, thus rendering it incapable of evolving CO2, removed its attractiveness to mosquitos. Treatment with vacuum alone, which may be expected to remove the volatile substances, did not completely remove the attractiveness; nor did the treatment with BaCl2 alone, which removes the bicarbonates in the blood.The attractiveness of blood was completely removed by desiccation and was not returned by remoistening. No attractive substance was isolated in an ether extract of blood.When CO2-freed blood was treated with gaseous CO2 its attractiveness was significantly increased. When the treatment was such as to restore the normal CO2-producing capacity, the attractiveness was one-half that of whole blood. The attractiveness of whole blood was not increased by adding excess CO2.It is concluded that the CO2 in beef blood is a definite element in its attractiveness, though probably not the most important one.

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Ligusticum sinense Nanoemulsion Gel as Potential Repellent against Aedes aegypti, Anopheles minimus, and Culex quinquefasciatus (Diptera: Culicidae)

Insects ◽

10.3390/insects12070596 ◽

2021 ◽

Vol 12 (7) ◽

pp. 596

Author(s):

Anuluck Junkum ◽

Wanchai Maleewong ◽

Atiporn Saeung ◽

Danita Champakaew ◽

Arpaporn Chansang ◽

...

Keyword(s):

Aedes Aegypti ◽

Culex Quinquefasciatus ◽

Disease Transmission ◽

Skin Irritation ◽

Mosquito Vectors ◽

Plant Family ◽

Anopheles Minimus ◽

Human Volunteers ◽

Nanoemulsion Gel ◽

Fresh Preparation

Ligusticum sinense Oliv. cv. is a species of Umbelliferae (Apiaceae), a large plant family in the order Apiales. In this study, L. sinense hexane extract nanoemulsion gel (LHE-NEG) was investigated for mosquito repellency and compared to the standard chemical, N,N-diethyl-3-methylbenzamide (DEET), with the goal of developing a natural alternative to synthetic repellents in protecting against mosquito vectors. The results demonstrated that LHE-NEG afforded remarkable repellency against Aedes aegypti, Anopheles minimus, and Culex quinquefasciatus, with median protection times (MPTs) of 5.5 (4.5–6.0), 11.5 (8.5–12.5), and 11.25 (8.5–12.5) h, respectively, which was comparable to those of DEET-nanoemulsion gel (DEET-NEG: 8.5 (7.0–9.0), 12.0 (10.0–12.5), and 12.5 (10.0–13.5) h, respectively). Evaluation of skin irritation in 30 human volunteers revealed no potential irritant from LHE-NEG. The physical and biological stability of LHE-NEG were determined after being kept under heating/cooling cycle conditions. The stored samples of LHE-NEG exhibited some changes in appearance and differing degrees of repellency between those kept for 3 and 6 heating/cooling cycles, thus providing slightly shorter MPTs of 4.25 (4.0–4.5) and 3.25 (2.5–3.5) h, respectively, when compared to those of 5.0 (4.5–6.0) h in fresh preparation. These findings encourage commercially developed LHE-based products as an alternative to conventional synthetic repellents in preventing mosquito bites and helping to interrupt mosquito-borne disease transmission.

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Permethrin Resistance in Aedes aegypti Affects Aspects of Vectorial Capacity

Insects ◽

10.3390/insects12010071 ◽

2021 ◽

Vol 12 (1) ◽

pp. 71

Author(s):

Tse-Yu Chen ◽

Chelsea T. Smartt ◽

Dongyoung Shin

Keyword(s):

Aedes Aegypti ◽

Sodium Channel ◽

Mosquito Control ◽

Vector Competence ◽

Vectorial Capacity ◽

Parental Population ◽

Control Programs ◽

Channel Gene ◽

Sodium Channel Gene ◽

Specific Pcr

Aedes aegypti, as one of the vectors transmitting several arboviruses, is the main target in mosquito control programs. Permethrin is used to control mosquitoes and Aedes aegypti get exposed due to its overuse and are now resistant. The increasing percentage of permethrin resistant Aedes aegypti has become an important issue around the world and the potential influence on vectorial capacity needs to be studied. Here we selected a permethrin resistant (p-s) Aedes aegypti population from a wild Florida population and confirmed the resistance ratio to its parental population. We used allele-specific PCR genotyping of the V1016I and F1534C sites in the sodium channel gene to map mutations responsible for the resistance. Two important factors, survival rate and vector competence, that impact vectorial capacity were checked. Results indicated the p-s population had 20 times more resistance to permethrin based on LD50 compared to the parental population. In the genotyping study, the p-s population had more homozygous mutations in both mutant sites of the sodium channel gene. The p-s adults survived longer and had a higher dissemination rate for dengue virus than the parental population. These results suggest that highly permethrin resistant Aedes aegypti populations might affect the vectorial capacity, moreover, resistance increased the survival time and vector competence, which should be of concern in areas where permethrin is applied.

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Investigating Male Aedes aegypti (Diptera: Culicidae) Attraction to Different Oviposition Containers Using Various Configurations of the Sound Gravid Aedes Trap

Journal of Medical Entomology ◽

10.1093/jme/tjz229 ◽

2019 ◽

Vol 57 (3) ◽

pp. 957-961

Author(s):

Kyran M Staunton ◽

Barukh B Rohde ◽

Michael Townsend ◽

Jianyi Liu ◽

Mark Desnoyer ◽

...

Keyword(s):

Aedes Aegypti ◽

Zika Virus ◽

Disease Transmission ◽

Urban Landscape ◽

Mosquito Control ◽

Transmission Risk ◽

Northern Australia ◽

Control Programs ◽

Male Dispersal ◽

Olfactory Attractant

Abstract Aedes aegypti (Linnaeus), the primary vectors of the arboviruses dengue virus and Zika virus, continue to expand their global distributions. In efforts to better control such species, several mosquito control programs are investigating the efficacy of rearing and releasing millions of altered male Aedes throughout landscapes to reduce populations and disease transmission risk. Unfortunately, little is known about Ae. aegypti, especially male, dispersal behaviors within urban habitats. We deployed Sound-producing Gravid Aedes Traps (SGATs) in Cairns, northern Australia, to investigate male Ae. aegypti attraction to various oviposition container configurations. The traps were arranged to include: 1) water only, 2) organically infused water, 3) infused water and L3 larvae, 4) infused water and a human-scented lure, and lastly 5) no water or olfactory attractant (dry). Our data suggest that males were more attracted to SGATs representing active larval sites than potential larval sites, but were equally attracted to dry SGATs relative to those containing water and/or infusion. Additionally, we found that female Ae. aegypti were equally attracted to wet SGATs, with or without infusion, but not dry ones. These results suggest that male Ae. aegypti within northern Australia are more attracted to active larval sites and equally attracted to dry containers as wet or infused ones. Additionally, female Ae. aegypti are unlikely to enter dry containers. Such findings contribute to our understanding of potentially attractive features for local and released Ae. aegypti throughout the northern Australian urban landscape.

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Studies on the Responses of the Female Aëdes Mosquito. Part II.—The Action of Liquid Repellent Compounds

Bulletin of Entomological Research ◽

10.1017/s0007485300025190 ◽

1951 ◽

Vol 42 (1) ◽

pp. 115-122 ◽

Cited By ~ 4

Author(s):

D. S. Sarkaria ◽

A. W. A. Brown

Keyword(s):

Aedes Aegypti ◽

Volatile Compounds ◽

Vapour Pressure ◽

Aedes Mosquito ◽

Large Cage ◽

Mosquito Repellents ◽

Protection Period

A number of liquid mosquito repellents were assessed for vapour repellency power in an olfactometer mounted in a very large cage filled with females of Aëdes aegypti. They were also tested for their knockdown power in fumigation bottles. Their vapour pressures were determined by the Ramsay-Young method.All the liquids showed vapour repellency, and in 39 out of the 42 tested this effect was highly significant. The highest vapour repellency ratings were shown by compounds already known to be the most effective repellents.Although the more volatile compounds such as citronellal tend to show the highest repellency ratings, nevertheless compounds of low vapour pressure such as indalone, DMP and isobornyl morpholinoacetate may also show high vapour repellency. It is concluded that vapour repellency, although in the first instance dependent upon volatility, can vary independently of vapour pressure, so that compounds may be found which afford not only a long protection period due to their nonvolatility, but also a high vapour repellency due to the potency of the comparatively few molecules that are volatilised.The vapours of most of the repellents were found to induce knockdown of mosquitos, but there was no correlation between the speed of this process and the vapour repellency of the compounds.

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Comparison of the Effect of Insecticides on Bumble Bees (Bombus impatiens) and Mosquitoes (Aedes aegypti and Culex quinquefasciatus) by Standard Mosquito Research Methods

Journal of Economic Entomology ◽

10.1093/jee/toaa282 ◽

2020 ◽

Author(s):

Bethany L McGregor ◽

Bryan V Giordano ◽

Alfred E Runkel ◽

Herbert N Nigg ◽

H Lee Nigg ◽

...

Keyword(s):

Aedes Aegypti ◽

Culex Quinquefasciatus ◽

Mosquito Control ◽

The United States ◽

Field Trials ◽

Bombus Impatiens ◽

Acute Effects ◽

Nontarget Effects ◽

Native North American ◽

Significant Mortality

Abstract Mosquito control districts in the United States are limited to two main classes of adulticides, pyrethroids and organophosphates, to control mosquitoes. Two adulticides used to control domestic mosquitoes are Fyfanon EW (malathion, organophosphate) and DeltaGard (deltamethrin, pyrethroid). While the effect of these pesticides on European honeybees (Apis mellifera L., Hymenoptera: Apidae) has been investigated, effects on native pollinators need additional research. The purpose of this study was to investigate the acute nontarget effects of these pesticides on Bombus impatiens Cresson (Hymenoptera: Apidae), a native North American bumble bee species, and compare these effects to wild and laboratory strains of mosquitoes (Aedes aegypti (L.) and Culex quinquefasciatus Say, Diptera: Culicidae) through field and laboratory assays. Bombus impatiens was found to be resistant to Fyfanon EW (x̅ = 6.7% mortality at 50-µg malathion per bottle) at levels that caused significant mortality to study mosquitoes (86.2 ≥ x̅ ≥ 100% mortality) in laboratory bottle bioassays. Comparatively, B. impatiens demonstrated greater mortality to DeltaGard (93.3%) at 2.5-µg deltamethrin/bottle than any mosquito colony assayed (14.1 ≥ x̅ ≥ 87.0% mortality). Only DeltaGard was tested in field applications. In the field, we observed acute effects of DeltaGard on mosquitoes and B. impatiens at 25- and 75-m distance from a truck-mounted ultra-low volume fogger, although treatment effects were not significant for B. impatiens. Additional wild-caught nontarget mortality to DeltaGard field trials was also evaluated. This study indicated that common mosquito control adulticides do cause nontarget mortality to B. impatiens but that impacts are variable depending on pesticide and further studies are needed.

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