Delayed mortality effects of cold fronts during the winter season on Aedes aegypti in a temperate region

AbstractIdentifying Aedes aegypti breeding hotspots in urban areas is crucial for the design of effective vector control strategies. Remote sensing techniques offer valuable tools for mapping habitat suitability. In this study, we evaluated the association between urban landscape, thermal features, and mosquito infestations. Entomological surveys were conducted between 2016 and 2019 in Vila Toninho, a neighborhood of São José do Rio Preto, São Paulo, Brazil, in which the numbers of adult female Ae. aegypti were recorded monthly and grouped by season for three years. We used data from 2016 to 2018 to build the model and data from summer of 2019 to validate it. WorldView-3 satellite images were used to extract land cover classes, and land surface temperature data were obtained using the Landsat-8 Thermal Infrared Sensor (TIRS). A multilevel negative binomial model was fitted to the data, which showed that the winter season has the greatest influence on decreases in mosquito abundance. Green areas and pavements were negatively associated, and a higher cover of asbestos roofs and exposed soil was positively associated with the presence of adult females. These features are related to socio-economic factors but also provide favorable breeding conditions for mosquitos. The application of remote sensing technologies has significant potential for optimizing vector control strategies, future mosquito suppression, and outbreak prediction.

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Daya Tetas Telur Aedes aegypty Strain Japan Yang Disimpan Selama Seminggu Pada Suhu Ekstrem

Bioeksperimen Jurnal Penelitian Biologi ◽

10.23917/bioeksperimen.v5i2.9243 ◽

2019 ◽

Vol 5 (2) ◽

pp. 131-135

Author(s):

I Gede Wempi Surya Permadi ◽

Yulian Taviv ◽

Lasbudi Pertama Ambarita

Keyword(s):

Aedes Aegypti ◽

Storage Time ◽

Winter Season ◽

Extreme Temperature ◽

Hemorrhagic Fever ◽

Cold Weather ◽

Multivariate Test ◽

The Public ◽

Number Of Patients ◽

And Storage

Dengue Hemorrhagic Fever (DHF) is one of the environmental health problems that several case increasing the number of patients and the wider area of distribution. The spread of dengue is influenced by several factors such as the vector disease, the behavior of people and the environment. In some sub-tropical countries is like in the winter season , a number of Aedes albopictus is found the eggs can still hatch at temperatures 0,5◦C. Eggs that will be tested for each treatment amounted to 100 eggs and had been through the process selected. The research carried in Parasitology and Entomology Labolatories, South Sumatra. The research was conducted from March to December 2014. In a multivariate test showed that the interaction of temperature and storage time affect the hatchability of eggs of Aedes aegypti strain Japan. Humidity and temperature can influence one of the insects are mosquitoes. At a certain temperature and humidity mosquitoes can not do the lifecycle and inhibite the morfology. The conclusion of this research is the cold storage and extreme temperature influence to eggs hacthingof Strain Japan the Aedes aegypti. Suggestions in this research is the public should continue to implement programs 3M plus, due to the Aedes eggs can survive in cold weather.

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Modeling of the Number of Cold Fronts in Cuba Using the Objective Regressive Regression (ROR) Methodology; Impact of Sunspots

Journal of Biomedical Research & Environmental Sciences ◽

10.37871/jbres1325 ◽

2021 ◽

Vol 2 (9) ◽

pp. 870-875

Author(s):

Ricardo Oses Rodriguez ◽

Rigoberto Fimia Duarte ◽

Alfredo Gonzalez Meneses

Keyword(s):

Standard Deviation ◽

Linear Correlation ◽

Winter Season ◽

Variable Number ◽

Enso Event ◽

Significant Trend ◽

Cold Fronts ◽

Significant Linear Correlation ◽

The Impact ◽

Ror Model

The objective of this work is to model the variable number of cold fronts that affect the Cuban territory in a winter season for a long series of data, to establish if the trend is significant and to see which are the main statistics of the model, to observe the impact of prediction using the number of sunspots with the help of Objective Regressive ROR modeling. In this work, the series of cold fronts per season that affect the Cuban territory was modeled in the years from the 1916-1917 seasons to the 2006-2007 seasons. There are more moderate cold fronts than any other front, on average there are more classic fronts than any other type, on average 19 fronts can be presented per season with a standard deviation of 4.8 Sunspots and they only have a significant linear correlation with sunspots. In moderate fronts, as the stains increase, the number of fronts decreases. The ROR model explains 98% of the variance with an error of 4.2 cases and depends on the fronts returned in 5 seasons, which could coincide with the ENSO event, and also depends on the number of sunspots returned in 12 years. From 1916-1917 approximately the 1952-1953 season, moderate fronts predominated, later from 1953-1954 to the end of the data, weak fronts predominate over the rest with some exceptions throughout history. No significant trend was observed in the model. It is concluded that forecasts of the number of cold fronts can be made with the variable number of sunspots.

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Rapid Immobilization of Adult Aedes aegypti Caused By Plant Essential Oils At Sublethal Concentrations

Journal of the American Mosquito Control Association ◽

10.2987/17-6721.1 ◽

2018 ◽

Vol 34 (3) ◽

pp. 210-216 ◽

Cited By ~ 1

Author(s):

Edmund J. Norris ◽

Maria Archevald-Cansobre ◽

Aaron D. Gross ◽

Lyric C. Bartholomay ◽

Joel R. Coats

Keyword(s):

Aedes Aegypti ◽

Essential Oils ◽

Adult Female ◽

Insect Pests ◽

Plant Essential Oils ◽

Knockdown Effect ◽

Test Population ◽

Insect Populations ◽

Delayed Mortality ◽

Sublethal Concentrations

ABSTRACT Many synthetic insecticides cause immobilization in insect pests after they are exposed. This immobilization or knockdown is an important feature of intoxication that contributes to the abatement of pest insect populations, while preventing vectors of disease from biting and spreading pathogenic organisms to susceptible individuals. We have previously demonstrated that certain plant essential oils rapidly immobilize adult female mosquitoes that have been exposed via topical application. To further characterize this effect, adult female Aedes aegypti were exposed to multiple concentrations of 32 commercially available plant essential oils, and immobilization at 1 h after exposure was recorded. The dose required to produce the 1-h knockdown effect in 50% of the test population (KD50) was calculated and compared with concentrations of each plant essential oil that caused mortality at 24 h. In the current study, multiple plant essential oils caused high percentage knockdown at 1 h at lower concentrations than concentrations that caused mortality at 24 h. Moreover, delayed mortality was observed in mosquitoes that were exposed to various concentrations of the 2 plant essential oils that produced significant knockdown at 1 h. These observations demonstrate an important characteristic of many plant essential oils and represent a novel means for which these oils may be incorporated into future insecticidal formulations.

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Effects of Constant and Fluctuating Low Temperatures on the Development of Aedes aegypti (Diptera: Culicidae) from a Temperate Region

Journal of Medical Entomology ◽

10.1093/jme/tjz087 ◽

2019 ◽

Vol 56 (6) ◽

pp. 1661-1668 ◽

Cited By ~ 3

Author(s):

María Sol De Majo ◽

Gabriela Zanotti ◽

Raúl E Campos ◽

Sylvia Fischer

Keyword(s):

Aedes Aegypti ◽

Low Temperatures ◽

Buenos Aires ◽

High Survival ◽

Immature Stages ◽

Temperate Region ◽

Development Times ◽

Average Survival ◽

Geographical Regions ◽

Aegypti Population

Abstract Most studies of the effects of low temperature on the development of immature stages of Aedes aegypti (L.) have been performed at constant temperatures in the laboratory, which may not accurately reflect the variable environmental conditions in the field. Thus, the aim of this study was to assess the effect of constant temperatures (CT) and fluctuating low temperatures (FT) on the fitness of Ae. aegypti of Buenos Aires, Argentina. Three CT treatments (12, 14, and 16°C) and three FT treatments (12, 14, and 16°C ± 4°C) were performed and then survival, development time, and size of adults analyzed for each treatment. The immature stages completed development in all the treatments, with an average survival of 88% at 16°C, 85% at 14°C, and 22% at 12°C, and showed no differences between the CT and FT treatments. Development times were similar between the CT and FT treatments at 16°C (average ± SD: 22.7 ± 2.0 d) and at 14°C (average ± SD: 30.5 ± 2.5 d), whereas at 12°C, they lasted longer under CT (average ± SD: 46.6 ± 5.1 d) than under FT (average ± SD: 37 ± 6.5 d). The sizes of the adults at 12 and 14°C were similar but larger than those at 16°C, and showed no differences between the CT and FT treatments. Compared to populations of other geographical regions assessed in previous studies, the shorter development times and the high survival at 14 and 16°C, and the ability to complete development at 12°C, a fact not previously reported, suggest that the Ae. aegypti population of Buenos Aires city has a higher tolerance to these conditions.

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Efficacy of targeted indoor residual spraying with the pyrrole insecticide chlorfenapyr against pyrethroid-resistant Aedes aegypti

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009822 ◽

2021 ◽

Vol 15 (10) ◽

pp. e0009822

Author(s):

Azael Che-Mendoza ◽

Gabriela González-Olvera ◽

Anuar Medina-Barreiro ◽

Carlos Arisqueta-Chablé ◽

Wilberth Bibiano-Marin ◽

...

Keyword(s):

Aedes Aegypti ◽

Urban Areas ◽

Indoor Residual Spraying ◽

Exposure Period ◽

Sugar Solution ◽

Monthly Basis ◽

Resting Sites ◽

Additive Mixed Models ◽

Residual Efficacy ◽

Delayed Mortality

Background There is an increased need to mitigate the emergence of insecticide resistance and incorporate new formulations and modes of application to control the urban vector Aedes aegypti. Most research and development of insecticide formulations for the control of Ae. aegypti has focused on their peridomestic use as truck-mounted ULV-sprays or thermal fogs despite the widespread knowledge that most resting Ae. aegypti are found indoors. A recent modification of indoor residual spraying (IRS), termed targeted IRS (TIRS) works by restricting applications to 1.5 m down to the floor and on key Ae. aegypti resting sites (under furniture). TIRS also opens the possibility of evaluating novel residual insecticide formulations currently being developed for malaria IRS. Methods We evaluated the residual efficacy of chlorfenapyr, formulated as Sylando 240SC, for 12 months on free-flying field-derived pyrethroid-resistant Ae. aegypti using a novel experimental house design in Merida, Mexico. On a monthly basis, 600 female Ae. aegypti were released into the houses and left indoors with access to sugar solution for 24 hours. After the exposure period, dead and alive mosquitoes were counted in houses treated with chlorfenapyr as well as untreated control houses to calculate 24-h mortality. An evaluation for these exposed cohorts of surviving mosquitoes was extended up to seven days under laboratory conditions to quantify “delayed mortality”. Results Mean acute (24-h) mortality of pyrethroid-resistant Ae. aegypti ranged 80–97% over 5 months, dropping below 30% after 7 months post-TIRS. If delayed mortality was considered (quantifying mosquito mortality up to 7 days after exposure), residual efficacy was above 90% for up to 7 months post-TIRS application. Generalized Additive Mixed Models quantified a residual efficacy of chlorfenapyr of 225 days (ca. 7.5 months). Conclusions Chlorfenapyr represents a new option for TIRS control of Ae. aegypti in urban areas, providing a highly-effective time of protection against indoor Ae. aegypti females of up to 7 months.

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