Workshop for priority-setting in Aedes aegypti control interventions in Latin America and the Caribbean: a policy dialogue

This article presents the results of a dialogue between decision-makers and experts in Latin America and the Caribbean on priority-setting for interventions and studies on Aedes aegypti control. The article is part of a project that included a systematic review of mosquito control strategies and a qualitative study with key informants from the region. Using a collective deliberative process assisted by the results of the above-mentioned projects, a list of priorities was developed by consensus for the implementation of vector control strategies and the development of key regional research lines. It was agreed that the best strategy is integrated vector management, divided into: (a) chemical control; (b) biological control; (c) environmental management; (d) community participation; and (e) integrated surveillance. The workshop highlighted the crucial role of government leadership and inter-sector coordination between government agencies and civil society stakeholders. The proposed priorities for research lines were: Ae. aegypti vector competence and associated factors; community components of interventions; incorporation of technology into vector control and monitoring; most efficient modalities of integrated surveillance; entomological indicators with the best predictive capacity; and resistance to insecticides. The policy dialogue methodology allowed validating and enriching the results of other levels of research, besides establishing priorities for regional research and control strategies.

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Predicting Aedes aegypti infestation using landscape and thermal features

Scientific Reports ◽

10.1038/s41598-020-78755-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Camila Lorenz ◽

Marcia C. Castro ◽

Patricia M. P. Trindade ◽

Maurício L. Nogueira ◽

Mariana de Oliveira Lage ◽

...

Keyword(s):

Remote Sensing ◽

Aedes Aegypti ◽

Vector Control ◽

Land Surface ◽

Urban Areas ◽

Negative Binomial ◽

Control Strategies ◽

Winter Season ◽

Landsat 8 ◽

Thermal Features

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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Urban Landscape Features Influence the Movement and Distribution of the Australian Container-Inhabiting Mosquito Vectors Aedes aegypti (Diptera: Culicidae) and Aedes notoscriptus (Diptera: Culicidae)

Journal of Medical Entomology ◽

10.1093/jme/tjz187 ◽

2019 ◽

Cited By ~ 1

Author(s):

Brendan J Trewin ◽

Daniel E Pagendam ◽

Myron P Zalucki ◽

Jonathan M Darbro ◽

Gregor J Devine ◽

...

Keyword(s):

Aedes Aegypti ◽

Urban Landscape ◽

Mosquito Control ◽

Control Strategies ◽

Oviposition Behavior ◽

Gaussian Kernel ◽

Mosquito Vectors ◽

Landscape Features ◽

Rainwater Tanks

Abstract Urban landscape features play an important role in the distribution and population spread of mosquito vectors. Furthermore, current insecticide and novel rear-and-release strategies for urban mosquito management rarely consider the spatial structure of the landscape when applying control practices. Here, we undertake a mark-recapture experiment to examine how urban features influence the movement and distribution of Australian container-inhabiting Aedes vectors. We pay attention to the role of semipermanent water storage containers, called rainwater tanks, and the influence of movement barriers, such as roads, on the spread and distribution of vector populations. Results suggest that Aedes aegypti (Linnaeus) (Diptera: Culicidae) were more likely to be captured around rainwater tanks, and that released males travel throughout residential blocks but do not cross roads. Conversely, female Aedes notoscriptus (Skuse) (Diptera: Culicidae) movement was uninhibited by roads and rainwater tanks did not influence female distribution or oviposition behavior. Using an isotropic Gaussian kernel framework, we show that vector movement is likely to be greater when applying a temporal effect, than when estimated by traditional methods. We conclude that a greater understanding on the role of urban features on vector movement will be important in the new age of rear-and-release mosquito control strategies, particularly those where estimations of movement are important for ensuring efficacy of application.

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Intracellular Interactions Between Arboviruses and Wolbachia in Aedes aegypti

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.690087 ◽

2021 ◽

Vol 11 ◽

Author(s):

Jerica Isabel L. Reyes ◽

Yasutsugu Suzuki ◽

Thaddeus Carvajal ◽

Maria Nilda M. Muñoz ◽

Kozo Watanabe

Keyword(s):

Aedes Aegypti ◽

Vector Control ◽

Host Species ◽

Control Strategies ◽

Cytoskeletal Proteins ◽

Cellular Interactions ◽

Cellular Mechanisms ◽

Cellular Regeneration ◽

Release Program ◽

Human Infections

Aedes aegypti is inherently susceptible to arboviruses. The geographical expansion of this vector host species has led to the persistence of Dengue, Zika, and Chikungunya human infections. These viruses take advantage of the mosquito’s cell to create an environment conducive for their growth. Arboviral infection triggers transcriptomic and protein dysregulation in Ae. aegypti and in effect, host antiviral mechanisms are compromised. Currently, there are no existing vaccines able to protect human hosts from these infections and thus, vector control strategies such as Wolbachia mass release program is regarded as a viable option. Considerable evidence demonstrates how the presence of Wolbachia interferes with arboviruses by decreasing host cytoskeletal proteins and lipids essential for arboviral infection. Also, Wolbachia strengthens host immunity, cellular regeneration and causes the expression of microRNAs which could potentially be involved in virus inhibition. However, variation in the magnitude of Wolbachia’s pathogen blocking effect that is not due to the endosymbiont’s density has been recently reported. Furthermore, the cellular mechanisms involved in this phenotype differs depending on Wolbachia strain and host species. This prompts the need to explore the cellular interactions between Ae. aegypti-arboviruses-Wolbachia and how different Wolbachia strains overall affect the mosquito’s cell. Understanding what happens at the cellular and molecular level will provide evidence on the sustainability of Wolbachia vector control.

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Genealogy of Resistant Tuberculosis in Latin America and the Caribbean until 2020

10.5772/intechopen.96280 ◽

2021 ◽

Author(s):

Onix J. Cantres-Fonseca ◽

Francisco Del Olmo-Arroyo

Keyword(s):

Latin America ◽

Multidrug Resistance ◽

Drug Exposure ◽

Control Strategies ◽

Treatment Resistance ◽

High Rate ◽

World Health ◽

Resistant Tuberculosis ◽

The World ◽

The Caribbean

History hallmarks different out brakes events during the last century. Being caught in the in the middle of the catastrophic COVID-19 pandemic, that initiated in 2019 makes possible to forget other causalities. Tuberculosis makes the case. The pathogen has been present more than hundredth years. Relevance rest in worldwide prevalence, pathogen spread, treatment resistance and the need for eradication. Drug treatment resistance is considered as one of the criteria to prioritize a country in the World Health Organization’s intention to eradicate tuberculosis infection in the world. For decades in Latin America, including the Caribbean, there have been a persistent high rate of drug resistance with an overall prevalence to one or more drug rounds 13.0%. Approximately 30% of previously treated cases have a multidrug resistance. In this chapter, we intend to review the epidemiology of resistant tuberculosis, and the causes of resistance associated to the community of people in the Latin American and the Caribbean. We intend to describe the genetic response of Mycobacterium tuberculosis from its migratory journey throughout decades from areas of Europa and Asia to Latin America, its genetic transformation secondary to inadequate drug exposure and the characteristics of the infected host, and how a change in the healthcare system and tuberculosis control strategies access are needed to change the surge of multidrug resistance tuberculosis.

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Intracellular Interactions between Arboviruses and Wolbachia in Aedes aegypti

10.20944/preprints202104.0151.v1 ◽

2021 ◽

Author(s):

Jerica Isabel Reyes ◽

Yasutsugu Suzuki ◽

Thaddeus Carvajal ◽

Maria Nilda Muñoz ◽

Kozo Watanabe

Keyword(s):

Aedes Aegypti ◽

Vector Control ◽

Control Strategies ◽

Host Responses ◽

Cellular Interactions ◽

Viral Inhibition ◽

Cellular Mechanisms ◽

Release Program ◽

Human Infections ◽

Cellular Components

Aedes aegypti is inherently susceptible to arboviruses. The geographical expansion of this vector host species has led to the persistence of Dengue, Zika and Chikungunya human infections. These viruses take advantage of the mosquito’s cell to create an environment conducive for their growth. Arboviral infection triggers transcriptomic and protein dysregulation in Ae. aegypti and in effect, host antiviral mechanisms are compromised. Currently, there are no existing vaccines able to protect human hosts from these infections and thus, vector control strategies such as Wolbachia mass release program is regarded as a viable option. Considerable evidence demonstrates how the presence of Wolbachia interferes with arboviruses by decreasing cellular components vital for the pathogen and strengthening antiviral host responses. However, variation in the magnitude of Wolbachia’s viral inhibition that is neither due to strain nor density has been observed. Furthermore, the cellular mechanisms involved in the endosymbiont’s pathogen-blocking differs among hosts. This prompts the need to explore the cellular interactions between Ae. aegypti-arboviruses-Wolbachia and how these interactions overall affect the mosquito’s cell. Understanding what happens at the cellular and molecular level will provide evidence on the sustainability of Wolbachia vector control.

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Evaluation of the resistance to insecticides in Aedes aegypti, transmitter of dengue, in Latin America

Mexican Journal of Medical Research ◽

10.29057/mjmr.v8i15.3912 ◽

2020 ◽

Vol 8 (15) ◽

pp. 23-28

Author(s):

Amparo Gabriela Hernández Ramos

Keyword(s):

Infectious Disease ◽

Latin America ◽

Aedes Aegypti ◽

Insecticide Resistance ◽

Vector Control ◽

Latin American ◽

Female Mosquito ◽

The World ◽

Different Seasons ◽

Latin American Countries

Dengue is an infectious disease with high rates of morbidity and mortality, transmitted by the bite of the female mosquito of the genus Aedes aegypti, vector distributed in tropical and subtropical areas throughout the world. America is one of the most affected regions. This vector is controlled through insecticides that due to its constant use in populations, a resistance phenomenon has been produced. The objective of this review is to identify the situation of insecticide resistance in populations of Aedes aegypti in Latin American countries. In this region, several insecticides have been used for vector control; in the last 10 years insecticides of the pyrethroid and organophosphorus group have been used as adulticides for the control of the mosquito, conditioning resistance. Some insecticides such as organophosphates and deltamethrin, despite of not being intensively used in Latin American countries, also show resistance. Improvements in vector control are required, including the rotation of the insecticides during the different seasons, as well as innovating techniques and forms of vector control

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Saving Women's Lives in Latin America and the Caribbean: Improving Cervical Cancer Screening and Treatment Quality and Access

Journal of Global Oncology ◽

10.1200/jgo.18.60200 ◽

2018 ◽

Vol 4 (Supplement 2) ◽

pp. 148s-148s

Author(s):

S. Beare ◽

A. Meglioli ◽

J. Burke ◽

N. Bandhoe ◽

J. López Gallardo

Keyword(s):

Cervical Cancer ◽

Latin America ◽

Cancer Screening ◽

Cervical Cancer Screening ◽

Western Hemisphere ◽

Civil Society Organizations ◽

Policy Dialogue ◽

Hpv Dna ◽

Cancer Services ◽

The Caribbean

Background and context: It is the third leading cause of cancer deaths among females in Latin America and the Caribbean, and yet cervical cancer is almost entirely preventable and treatable. In a region where many lack even basic access to quality sexual and reproductive healthcare, screening and treatment services for HPV and cervical cancer are far from universally available. International Planned Parenthood Federation/Western Hemisphere Region (IPPF/WHR) and its member associations (MAs) are working to reverse this trend, identifying and bridging local gaps in access and services wherever possible. Aim: IPPF/WHR and its MAs seek to improve both providers' ability to deliver - and women's ability to access - quality cervical cancer screening and treatment through institutional capacity building, the introduction of new technologies, advocacy and community awareness efforts. Strategy/Tactics: 1) Increase cervical cancer services by training providers in the provision of low cost, high capacity screening and treatment methods, including visual inspection with acetic acid (VIA), HC2 and HPV DNA screening technologies, and a single-visit approach (SVA) to treatment using cryotherapy, thermocoagulation and LEEP. 2) Educate populations and increase demand for cervical cancer services by implementing public awareness campaigns and community information, education and communication (IEC) activities promoting the importance of early detection and treatment. 3) Improve and standardize clinical protocols and referral pathways by advocating among and collaborating with key decision-makers and local ministries of health. Program/Policy process: MAs are implementing small-scale pilot studies to incorporate VIA, HC2 and HPV DNA screening and new treatment to provide even greater numbers of women with potentially life-saving diagnostics and care in Belize, Honduras, El Salvador and Bolivia. As leading clinical experts and advocates, several MAs are also working with public sector counterparts to refine two-way referral pathways, standardize screening protocols and clinical guidelines, and to ensure data quality and collection. A range of Caribbean MAs have also been trained in the use of VIA, cryo and LEEP. Outcomes: From 2016 to 2017, MAs from Belize, Grenada, Suriname, and several additional Caribbean countries who received training in VIA and other screening and treatment techniques saw an average 7% increase in the number of direct cervical cancer services provided. MAs from Belize, Bolivia and Honduras also contributed to updated national cervical cancer protocols. What was learned: An effective national response to cervical cancer requires the support and collaboration of civil society organizations, which can deliver direct services and play a catalytic role in advancing technical recommendations and policy dialogue. Countries should continue to improve the quality of VIA services, until more advanced screening technologies become available and can be scaled up.

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The juvenile hormone receptor Methoprene-tolerant is involved in the sterilizing effect of pyriproxyfen on adult Aedes aegypti mosquitoes

10.1101/2020.05.31.126508 ◽

2020 ◽

Author(s):

Tahmina Hossain Ahmed ◽

T. Randolph Saunders ◽

Donald Mullins ◽

Mohammad Zillur Rahman ◽

Jinsong Zhu

Keyword(s):

Aedes Aegypti ◽

Juvenile Hormone ◽

Mosquito Control ◽

Fat Body ◽

Control Strategies ◽

Follicular Development ◽

Blood Feeding ◽

Oocyte Development ◽

Hormonal Responses ◽

Before And After

AbstractExposure of adult mosquitoes to pyriproxyfen (PPF), an analog of insect juvenile hormone (JH), has shown promise to effectively sterilize female mosquitoes. However, the underlying mechanisms of the PPF-induced decrease in mosquito fecundity are largely unknown. We performed a comprehensive study to dissect the mode of PPF action in Aedes aegypti mosquitoes. Exposure to PPF prompted the overgrowth of primary follicles in sugar-fed Ae. aegypti females but blocked the development of primary follicles at Christopher’s Stage III after blood feeding. Secondary follicles were precociously activated in PPF-treated mosquitoes. Moreover, PPF substantially altered the expression of many genes that are essential for mosquito physiology and oocyte development in the fat body and ovary. In particular, many metabolic genes were differentially expressed in response to PPF treatment, thereby affecting the mobilization and utilization of energy reserves. Furthermore, PPF treatment on the previtellogenic female adults considerably modified mosquito responses to JH and 20-hydroxyecdysone (20E), two major hormones that govern mosquito reproduction. Krüppel homolog 1, a JH-inducible transcriptional regulator, showed consistently elevated expression after PPF exposure. Conversely, PPF upregulated the expression of several key players of the 20E regulatory cascades, including HR3 and E75A, in the previtellogenic stage. After blood-feeding, the expression of these 20E response genes was significantly weaker in PPF-treated mosquitoes than the solvent-treated control groups. RNAi-mediated knockdown of the Methoprene-tolerant (Met) protein, the JH receptor, partially rescued the impaired follicular development after PPF exposure and substantially increased the hatching of the eggs produced by PPF-treated female mosquitoes. Thus, the results suggested that PPF relied on Met to exert its sterilizing effects on female mosquitoes. In summary, this study finds that PPF exposure disturbs normal hormonal responses and metabolism in Ae. aegypti, shedding light on the molecular targets and the downstream signaling pathways activated by PPF.Author summaryAedes aegypti mosquitoes are responsible for the transmission of dengue, yellow fever, chikungunya, and Zika fever. Insecticides are widely used as the primary tool in the prevention and control of these infectious diseases. In light of the rapid increase of insecticide resistance in mosquito populations, there is an urgent need to find new classes of insecticides with a different mode of action. Here we found that pyriproxyfen, an analog of insect juvenile hormone (JH), had a large impact on the oocyte development, both before and after blood feeding, in female mosquitoes. Pyriproxyfen disturbed normal hormonal responses and caused metabolic shifting in female adults. These actions appear to collectively impair oocyte development and substantially reduce viable progenies of female mosquitoes. Besides, we demonstrated the involvement of the JH receptor Met in pyriproxyfen-induced female sterilization. This study significantly advances our understanding of mosquito reproductive biology and the molecular basis of pyriproxyfen action, which are invaluable for the development of new mosquito control strategies.

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Behavior-based control of arthropod vectors: the case of mosquitoes, ticks, and Chagasic bugs

10.1093/oso/9780198797500.003.0021 ◽

2018 ◽

Author(s):

Ana E. Gutiérrez-Cabrera ◽

Giovanni Benelli ◽

Thomas Walker ◽

José Antonio De Fuentes-Vicente ◽

Alex Córdoba-Aguilar

Keyword(s):

Vector Control ◽

Behavioral Ecology ◽

Mosquito Control ◽

Control Strategies ◽

Tick Control ◽

Arthropod Vectors ◽

Behavior Based Control ◽

Control Programmes ◽

Behavior Based ◽

Mosquito Behavior

This chapter outlines the patterns and occurrences of major diseases transmitted by arthropod vectors, highlighting the need for behavior-based control strategies, first, focusing on mosquito control tools with an emphasis on how knowledge of mosquito behavioral ecology may help vector control programmes. The potential of sound traps, swarm manipulation, ‘lure and kill’, radiation, transgenicm and symbiont-based approaches will be outlined, and how mosquito behavior influences these vector control strategies. Secondly, tick control strategies, as well as pheromone-assisted tick control will be reviewed, with special reference to pheromone-assisted matrix for application to vegetation, tick decoy, bont tick decoy, and the deployment of confusants. Thirdly, how Chagasic bugs are traditionally controlled will be summarized. Also, we highlight emerging chemical-based attraction methods, employing bug pheromones, as well as the use of entomopathogens. This review is not a thorough one, as it should only instruct students on how to use arthropod behavior to control arthropod vectors.

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Current Status of Aedes aegypti Insecticide Resistance Development from Banjarmasin, Kalimantan, Indonesia

BioMed Research International ◽

10.1155/2018/1735358 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 9

Author(s):

P. H. Hamid ◽

V. I. Ninditya ◽

J. Prastowo ◽

A. Haryanto ◽

A. Taubert ◽

...

Keyword(s):

Aedes Aegypti ◽

Insecticide Resistance ◽

Point Mutation ◽

Mosquito Control ◽

Control Strategies ◽

Current Status ◽

Resistance Development ◽

Health Authorities ◽

Public Health Authorities ◽

High Level

Aedes aegypti represents the principal vector of many arthropod-borne diseases in tropical areas worldwide. Since mosquito control strategies are mainly based on use of insecticides, resistance development can be expected to occur in frequently exposed Ae. aegypti populations. Surveillance on resistance development as well as testing of insecticide susceptibility is therefore mandatory and needs further attention by national/international public health authorities. In accordance, we here conducted a study on Ae. aegypti resistance development towards several often used insecticides, i.e., malathion, deltamethrin, permethrin, λ-cyhalothrin, bendiocarb, and cyfluthrin, in the periurban area of Banjarmasin city, Kalimantan, Indonesia. Our results clearly showed resistance development of Ae. aegypti populations against tested insecticides. Mortalities of Ae. aegypti were less than 90% with the highest resistance observed against 0.75% permethrin. Collected mosquitoes from Banjarmasin also presented high level of resistance development to 0.1% bendiocarb. Molecular analysis of voltage-gated sodium channel (Vgsc) gene showed significant association of V1016G gene point mutation in resistance Ae. aegypti phenotypes against 0.75% permethrin. However, F1534C gene point mutation did not correlate to Ae. aegypti insecticide resistance to 0.75% permethrin. Irrespective of periurban areas in Kalimantan considered as less densed island of Indonesia, Ae. aegypti-derived resistance to different routinely applied insecticides occurred. Our findings evidence that Ae. aegypti insecticide resistance is most likely spreading into less populated areas and thus needs further surveillance in order to delay Ae. aegypti resistance development.

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