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Troyo A, González-Sequeira MP, Aguirre-Salazar M, Cambronero-Ortíz I, Chaves-González LE, Mejías-Alpízar MJ, Alvarado-Molina K, Calderón-Arguedas Ó, Rojas-Araya D. Acknowledging extraordinary women in the history of medical entomology. Parasit Vectors 2022; 15:114. [PMID: 35361284 PMCID: PMC8969321 DOI: 10.1186/s13071-022-05234-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/08/2022] [Indexed: 11/29/2022] Open
Abstract
Throughout history, women have been actively involved in the advancement of science, while struggling to overcome challenges to participate and a lack of recognition. Prior to 1950, most women were not included in the lists of "classical" descriptions of the iconic scientific figures nor included in the most relevant historical accounts. Since the second half of the twentieth century, great efforts have been made to recognize the contributions of women to the advancement of science, especially since formal scientific careers have been dominated by men, with limited (or no) access to women. Despite these challenging social, political and cultural contexts, many women have succeeded in making significant advancements, and their contributions are now being acknowledged. Such efforts have led to the publication of recent reviews and compilations on outstanding women in biological sciences. The field of medical entomology is inherently interdisciplinary, focusing on insects and other arthropods that affect human health, with input primarily from the biological and medical sciences and a strong public health perspective. Several reviews and book chapters describing the history of medical entomology have been published over the decades, but few women are mentioned in these publications, even though many women have contributed to this field. Much of the information on these women is currently scattered throughout the published literature and historical records on a wide range of topics, including activism, virology, vector control and even acarology. Considering that there is no single available compilation of women contributors in the history of medical entomology, this review aims to provide a list of 22 women and their contributions to this field. The list includes women from diverse backgrounds, born in the late 1800s and before 1950, who directly impacted medical entomology in various ways and in different regions of the world. This compilation is far from exhaustive, but it aims to identify role models and examples of extraordinary women to motivate the evolving future of this field.
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Affiliation(s)
- Adriana Troyo
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
| | - María Paula González-Sequeira
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
| | - Mónica Aguirre-Salazar
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
| | - Ian Cambronero-Ortíz
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
| | - Luis Enrique Chaves-González
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
| | - María José Mejías-Alpízar
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
| | - Kendall Alvarado-Molina
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
| | - Ólger Calderón-Arguedas
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
| | - Diana Rojas-Araya
- Laboratorio de Investigación en Vectores, Centro de Investigación en Enfermedades Tropicales, Sección de Entomología Médica, Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica
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Gomulski LM, Manni M, Carraretto D, Nolan T, Lawson D, Ribeiro JM, Malacrida AR, Gasperi G. Transcriptional variation of sensory-related genes in natural populations of Aedes albopictus. BMC Genomics 2020; 21:547. [PMID: 32767966 PMCID: PMC7430840 DOI: 10.1186/s12864-020-06956-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/27/2020] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The Asian tiger mosquito, Aedes albopictus, is a highly dangerous invasive vector of numerous medically important arboviruses including dengue, chikungunya and Zika. In four decades it has spread from tropical Southeast Asia to many parts of the world in both tropical and temperate climes. The rapid invasion process of this mosquito is supported by its high ecological and genetic plasticity across different life history traits. Our aim was to investigate whether wild populations, both native and adventive, also display transcriptional genetic variability for functions that may impact their biology, behaviour and ability to transmit arboviruses, such as sensory perception. RESULTS Antennal transcriptome data were derived from mosquitoes from a native population from Ban Rai, Thailand and from three adventive Mediterranean populations: Athens, Greece and Arco and Trento from Italy. Clear inter-population differential transcriptional activity was observed in different gene categories related to sound perception, olfaction and viral infection. The greatest differences were detected between the native Thai and the Mediterranean populations. The two Italian populations were the most similar. Nearly one million quality filtered SNP loci were identified. CONCLUSION The ability to express this great inter-population transcriptional variability highlights, at the functional level, the remarkable genetic flexibility of this mosquito species. We can hypothesize that the differential expression of genes, including those involved in sensory perception, in different populations may enable Ae. albopictus to exploit different environments and hosts, thus contributing to its status as a global vector of arboviruses of public health importance. The large number of SNP loci present in these transcripts represents a useful addition to the arsenal of high-resolution molecular markers and a resource that can be used to detect selective pressure and adaptive changes that may have occurred during the colonization process.
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Affiliation(s)
- Ludvik M Gomulski
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Mosè Manni
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
- Department of Genetic Medicine and Development, University of Geneva Medical School, and Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Davide Carraretto
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Tony Nolan
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Daniel Lawson
- Department of Life Sciences, Imperial College London, London, UK
| | - José M Ribeiro
- NIAID, Laboratory of Malaria and Vector Research, NIH, Rockville, MD, 20852, USA
| | - Anna R Malacrida
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Giuliano Gasperi
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy.
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Abstract
Dengue virus (DENV) belongs to the family Flaviviridae, genus Flavivirus. It is a single-stranded positive-sense ribonucleic acid virus with 10,700 bases. The genus Flavivirus includes other arthropod borne viruses such as yellow fever virus, West Nile virus, Zika virus, tick-borne encephalitis virus. It infects ~50–200 million people annually, putting over 3.6 billion people living in tropical regions at risk and causing ~20,000 deaths annually. The expansion of dengue is attributed to factors such as the modern dynamics of climate change, globalization, travel, trade, socioeconomics, settlement, and also viral evolution. There are four antigenically different serotypes of DENV based on the differences in their viral structural and nonstructural proteins. DENV infection causes a spectrum of illness ranging from asymptomatic to dengue fever to severe dengue shock syndrome. Infection with one serotype confers lifelong immunity against that serotype, but heterologus infection leads to severe dengue hemorrhagic fever due to antibody-dependent enhancement. Diagnosis of dengue infections is based mainly on serological detection of either antigen in acute cases or antibodies in both acute and chronic infection. Viral detection and real-time PCR detection though helpful is not feasible in resource poor setup. Treatment of dengue depends on symptomatic management along with fluid resuscitation and may require platelet transfusion. Although vaccine development is in late stages of development, developing a single vaccine against four serotypes often causes serious challenges to researchers; hence, the main stay of prevention is vector control and management.
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Ruedas G, Peña H, Brisco A, Fujioka KK, Wekesa JW. Life Histories and Other Biological Characteristics Enabling the Establishment of Aedes albopictus in the San Gabriel Valley, California. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2018; 34:93-98. [PMID: 31442161 DOI: 10.2987/17-6699.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Since Aedes albopictus was discovered in 2011 in the San Gabriel Valley it has become widespread despite the "harsh" environmental conditions and intense efforts to control or eliminate it. Species introduced into a new area may survive, thrive, or disappear depending on whether its new environment is suitable. The San Gabriel Valley Mosquito and Vector Control District expended considerable resources from 2011 to 2015 to eradicate this invasive species or, at a minimum, control and manage its spread. Despite the intense effort, the distribution of Ae. albopictus steadily expanded. Over those 5 years this increase shifted from a geometric to exponential pattern. What enabled Ae. albopictus to survive initially, become established, and then expand their distribution when ecological conditions in southern California were considered hostile for this invasive species? This study explores several biological characteristics including skip oviposition, installment egg hatching, and variable larval development that may have helped Ae. albopictus flourish in its new environment.
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Muzari MO, Devine G, Davis J, Crunkhorn B, van den Hurk A, Whelan P, Russell R, Walker J, Horne P, Ehlers G, Ritchie S. Holding back the tiger: Successful control program protects Australia from Aedes albopictus expansion. PLoS Negl Trop Dis 2017; 11:e0005286. [PMID: 28192520 PMCID: PMC5305203 DOI: 10.1371/journal.pntd.0005286] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 12/22/2016] [Indexed: 12/23/2022] Open
Abstract
Background The Asian tiger mosquito, Aedes albopictus, is an important vector of dengue, chikungunya and Zika viruses and is a highly invasive and aggressive biter. Established populations of this species were first recognised in Australia in 2005 when they were discovered on islands in the Torres Strait, between mainland Australia and Papua New Guinea. A control program was implemented with the original goal of eliminating Ae. albopictus from the Torres Strait. We describe the evolution of management strategies that provide a template for Ae. albopictus control that can be adopted elsewhere. Methodology / Principal findings The control strategy implemented between 2005 and 2008 targeted larval habitats using source reduction, insect-growth regulator and pyrethroid insecticide to control larvae and adults in the containers. However, the infrequency of insecticide reapplication, the continual accumulation and replacement of containers, and imminent re-introduction of mosquitoes through people’s movement from elsewhere compromised the program. Consequently, in 2009 the objective of the program changed from elimination to quarantine, with the goal of preventing Ae albopictus from infesting Thursday and Horn islands, which are the transport hubs connecting the Torres Strait to mainland Australia. However, larval control strategies did not prevent the species establishing on these islands in 2010. Thereafter, an additional strategy adopted by the quarantine program in early 2011 was harborage spraying, whereby the vegetated, well shaded resting sites of adult Ae. albopictus were treated with a residual pyrethroid insecticide. Inclusion of this additional measure led to a 97% decline in Ae. albopictus numbers within two years. In addition, the frequency of container treatment was increased to five weeks between treatments, compared to an average of 8 weeks that occurred in the earlier iterations of the program. By 2015 and 2016, Ae. albopictus populations on the two islands were undetectable in 70–90% of surveys conducted. Importantly, a comprehensive surveillance network in selected strategic areas has not identified established populations of this species on the Australian mainland. Conclusions / Significance The program has successfully reduced Ae. albopictus populations on Thursday Island and Horn Island to levels where it is undetectable in up to 90% of surveys, and has largely removed the risk of mainland establishment via that route. The vector management strategies adopted in the later years of the program have been demonstrably successful and provide a practical management framework for dengue, chikungunya or Zika virus outbreaks vectored by Ae. albopictus. As of June 2016, Ae. albopictus had not established on the Australian mainland and this program has likely contributed significantly to this outcome. Aedes albopictus is a disease vector and biting nuisance of major public health concern. Established populations of Ae. albopictus were first recognised in Australia in 2005 after they were discovered on islands in the Torres Strait. Consequently, a control program was established in the same year to eliminate Ae. albopictus populations in the Torres Strait in order to reduce the risk of disease, as well as to prevent the mosquito from spreading to the mainland of Australia. In 2009, the goal of the program changed from elimination to quarantine (cordon sanitaire) focusing mainly on the inner islands of Thursday Island and Horn Island, which are the major population, administrative and transport centres linking the Torres Strait region to the Australian mainland. The cordon sanitaire strategy involved an integrated approach composed of harborage spraying, source reduction, insecticide treatment of containers, lethal tire piles, mosquito population monitoring and public awareness campaigns. Strategic improvements in management techniques led to a 97% decline in Ae. albopictus numbers on the two islands between 2011 and 2012. By 2015, the program had successfully reduced Ae. albopictus populations on Thursday Island and Horn Island to levels where the species was frequently undetectable, and had largely removed the risk of mainland incursion via that route. In 2016 the improved management strategies were also adopted to successfully control a dengue outbreak in which Ae. albopictus was the implicated vector on two outer islands of the Torres Strait.
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Affiliation(s)
- Mutizwa Odwell Muzari
- Medical Entomology, Tropical Public Health Services Cairns, Cairns and Hinterland Hospital & Health Services, Cairns, Queensland, Australia
- * E-mail:
| | - Gregor Devine
- Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, Royal Brisbane Hospital, Herston, Queensland, Australia
| | - Joseph Davis
- Medical Entomology, Tropical Public Health Services Cairns, Cairns and Hinterland Hospital & Health Services, Cairns, Queensland, Australia
| | - Bruce Crunkhorn
- Medical Entomology, Tropical Public Health Services Cairns, Cairns and Hinterland Hospital & Health Services, Cairns, Queensland, Australia
| | - Andrew van den Hurk
- Public Health Virology, Forensic and Scientific Services, Department of Health, Queensland Government, Archerfield, Queensland, Australia
| | - Peter Whelan
- Biting Insect Technical & Extension Services, Nightcliff, Northern Territory, Australia
| | - Richard Russell
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - James Walker
- Northern Australia Quarantine Strategy, Department of Agriculture and Water Resources, Cairns, Queensland, Australia
| | - Peter Horne
- Health Surveillance, Tropical Public Health Services Cairns, Cairns and Hinterland Hospital & Health Services, Cairns, Queensland, Australia
| | - Gerhard Ehlers
- Medical Entomology, Tropical Public Health Services Cairns, Cairns and Hinterland Hospital & Health Services, Cairns, Queensland, Australia
| | - Scott Ritchie
- College of Public Health, Medical and Veterinary Sciences, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
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Manni M, Guglielmino CR, Scolari F, Vega-Rúa A, Failloux AB, Somboon P, Lisa A, Savini G, Bonizzoni M, Gomulski LM, Malacrida AR, Gasperi G. Genetic evidence for a worldwide chaotic dispersion pattern of the arbovirus vector, Aedes albopictus. PLoS Negl Trop Dis 2017; 11:e0005332. [PMID: 28135274 PMCID: PMC5300280 DOI: 10.1371/journal.pntd.0005332] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 02/09/2017] [Accepted: 01/16/2017] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Invasive species represent a global concern for their rapid spread and the possibility of infectious disease transmission. This is the case of the global invader Aedes albopictus, the Asian tiger mosquito. This species is a vector of medically important arboviruses, notably chikungunya (CHIKV), dengue (DENV) and Zika (ZIKV). The reconstruction of the complex colonization pattern of this mosquito has great potential for mitigating its spread and, consequently, disease risks. METHODOLOGY/PRINCIPAL FINDINGS Classical population genetics analyses and Approximate Bayesian Computation (ABC) approaches were combined to disentangle the demographic history of Aedes albopictus populations from representative countries in the Southeast Asian native range and in the recent and more recently colonized areas. In Southeast Asia, the low differentiation and the high co-ancestry values identified among China, Thailand and Japan indicate that, in the native range, these populations maintain high genetic connectivity, revealing their ancestral common origin. China appears to be the oldest population. Outside Southeast Asia, the invasion process in La Réunion, America and the Mediterranean Basin is primarily supported by a chaotic propagule distribution, which cooperates in maintaining a relatively high genetic diversity within the adventive populations. CONCLUSIONS/SIGNIFICANCE From our data, it appears that independent and also trans-continental introductions of Ae. albopictus may have facilitated the rapid establishment of adventive populations through admixture of unrelated genomes. As a consequence, a great amount of intra-population variability has been detected, and it is likely that this variability may extend to the genetic mechanisms controlling vector competence. Thus, in the context of the invasion process of this mosquito, it is possible that both population ancestry and admixture contribute to create the conditions for the efficient transmission of arboviruses and for outbreak establishment.
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Affiliation(s)
- Mosè Manni
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | | | - Francesca Scolari
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Anubis Vega-Rúa
- Laboratory of Medical Entomology, Environment and Health Unit, Morne Jolivière, Institut Pasteur of Guadeloupe, Les Abymes, Guadeloupe (French West Indies)
- Department of Virology, Arboviruses and Insect Vectors Unit, Institut Pasteur, Paris, France
| | - Anna-Bella Failloux
- Department of Virology, Arboviruses and Insect Vectors Unit, Institut Pasteur, Paris, France
| | - Pradya Somboon
- Department of Parasitology, Chiang Mai University, Chiang Mai, Thailand
| | - Antonella Lisa
- Computational Biology Unit, Institute of Molecular Genetics-National Research Council, Pavia, Italy
| | - Grazia Savini
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | | | - Ludvik M. Gomulski
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Anna R. Malacrida
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Giuliano Gasperi
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
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Hahn MB, Eisen RJ, Eisen L, Boegler KA, Moore CG, McAllister J, Savage HM, Mutebi JP. Reported Distribution of Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus in the United States, 1995-2016 (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2016; 53:1169-1175. [PMID: 27282817 PMCID: PMC9379858 DOI: 10.1093/jme/tjw072] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 04/18/2016] [Indexed: 05/03/2023]
Abstract
Aedes (Stegomyia) aegypti (L.) and Aedes (Stegomyia) albopictus (Skuse) transmit arboviruses that are increasing threats to human health in the Americas, particularly dengue, chikungunya, and Zika viruses. Epidemics of the associated arboviral diseases have been limited to South and Central America, Mexico, and the Caribbean in the Western Hemisphere, with only minor localized outbreaks in the United States. Nevertheless, accurate and up-to-date information for the geographical ranges of Ae. aegypti and Ae. albopictus in the United States is urgently needed to guide surveillance and enhance control capacity for these mosquitoes. We compiled county records for presence of Ae. aegypti and Ae. albopictus in the United States from 1995-2016, presented here in map format. Records were derived from the Centers for Disease Control and Prevention ArboNET database, VectorMap, the published literature, and a survey of mosquito control agencies, university researchers, and state and local health departments. Between January 1995 and March 2016, 183 counties from 26 states and the District of Columbia reported occurrence of Ae. aegypti, and 1,241 counties from 40 states and the District of Columbia reported occurrence of Ae. albopictus. During the same time period, Ae. aegypti was collected in 3 or more years from 94 counties from 14 states and the District of Columbia, and Ae. albopictus was collected during 3 or more years from 514 counties in 34 states and the District of Columbia. Our findings underscore the need for systematic surveillance of Ae. aegypti and Ae. albopictus in the United States and delineate areas with risk for the transmission of these introduced arboviruses.
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Affiliation(s)
- Micah B Hahn
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, Colorado 80521 (; ; ; ; ; ; )
| | - Rebecca J Eisen
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, Colorado 80521 (; ; ; ; ; ; )
| | - Lars Eisen
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, Colorado 80521 (; ; ; ; ; ; )
| | - Karen A Boegler
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, Colorado 80521 (; ; ; ; ; ; )
| | - Chester G Moore
- Department of Microbiology, Immunology and Pathology, Colorado State University, 3195 Rampart Road, Fort Collins, Colorado 80523
| | - Janet McAllister
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, Colorado 80521 (; ; ; ; ; ; )
| | - Harry M Savage
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, Colorado 80521 (; ; ; ; ; ; )
| | - John-Paul Mutebi
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, Colorado 80521 (; ; ; ; ; ; )
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Lacour G, Chanaud L, L’Ambert G, Hance T. Seasonal Synchronization of Diapause Phases in Aedes albopictus (Diptera: Culicidae). PLoS One 2015; 10:e0145311. [PMID: 26683460 PMCID: PMC4686165 DOI: 10.1371/journal.pone.0145311] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 12/01/2015] [Indexed: 11/18/2022] Open
Abstract
In temperate areas, population dynamics of the invasive Asian tiger mosquito Aedes albopictus are strongly affected by winter. The work we present here analyzes the adaptive synchronization of the diapause process in the wintry generation of A. albopictus, where the egg stage is exposed to adverse winter conditions. The seasonal pattern of egg laying activity of a French Mediterranean population of the Asian tiger mosquito was monitored weekly for 2 years with ovitraps. The field diapause incidence and the critical photoperiod (CPP, i.e. the maternal day length inducing diapause in 50% of the eggs), were determined by hatching experiments on the collected eggs. The period of diapause termination was estimated by a field survey of the first hatchings for both years. The CPP is equal to 13.5 hours of light and occurs in the field on the 25th of August. Thus, it is on September 11th, 17 days after the CPP, that 50% of the eggs are in a prediapause stage in the field. The egg diapause rate increases rapidly during September, whereas the mean number of eggs laid decreases sharply after mid-September. Surprisingly, after having reached a peak of 95% at the end of September, from mid-October the diapause incidence declined and stayed below 50%. Indeed, both years the diapause initiates before the rapid decrease of the environmental temperature. This leaves a sufficient period of time to the complete development of one generation of A. albopictus with effective induction of diapause in the laid eggs. The very first larvae hatched were sampled both years in the first half of March. With 20 to 26 weeks in the egg stage and about 7 weeks in the larval stages, the first annual generation spends a long time in immature stages. On a practical point of view, this long development time represents a wide window for eggs and larvae control in early spring.
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Affiliation(s)
- Guillaume Lacour
- EID Méditerranée, Montpellier, France
- Centre de Recherche sur la Biodiversité, Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgique
| | | | | | - Thierry Hance
- Centre de Recherche sur la Biodiversité, Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgique
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Lacour G, Vernichon F, Cadilhac N, Boyer S, Lagneau C, Hance T. When mothers anticipate: effects of the prediapause stage on embryo development time and of maternal photoperiod on eggs of a temperate and a tropical strains of Aedes albopictus (Diptera: Culicidae). JOURNAL OF INSECT PHYSIOLOGY 2014; 71:87-96. [PMID: 25450563 DOI: 10.1016/j.jinsphys.2014.10.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 10/09/2014] [Accepted: 10/13/2014] [Indexed: 06/04/2023]
Abstract
BACKGROUND The diapause of Aedes albopictus is maternally induced by photoperiod and initiates at the pharate larvae stage in eggs. This pre-diapause results in enhanced survival eggs during the winter. This study aims to disentangle the effects of photoperiod and diapause on embryonic developmental time and egg size in A. albopictus. A temperate strain capable to perform diapause and a tropical strain unable of diapause were reared at 21°C with long-(LD) and short-day (SD) lengths. Four distinct traits were studied on embryos and eggs were measured at the end of embryogenesis. RESULTS The chronologies of embryo development for both strains were influenced by maternal photoperiod, especially in the temperate strain in which the development of SD eggs took longer than LD eggs. The delay increased gradually in the temperate strain, and reached up to 38 h at the end of embryogenesis. The kinetics of embryogenesis differed among the temperate and the tropical strains, each one of the 4 studied traits showing differences. For example the serosal cuticle was secreted precociously in the tropical strain. Egg width and volume are influenced by the maternal photoperiod and the strain×photoperiod interaction. For both strains, larger eggs were laid by female reared under SD when compared to LD. CONCLUSIONS The influence of several maternal effects was demonstrated in this study. The diapause process modifies greatly the length of embryogenesis in the temperate strain, whereas the maternal photoperiod has a direct influence on egg size and embryogenesis regardless of the strain considered. These findings provide useful data on chronology of embryonic development for integrative biology studies of egg pre-diapause stages.
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Affiliation(s)
- Guillaume Lacour
- EID Méditerranée, 165 Avenue Paul-Rimbaud, 34184 Montpellier, France; Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.
| | - Florian Vernichon
- EID Méditerranée, 165 Avenue Paul-Rimbaud, 34184 Montpellier, France.
| | - Nicolas Cadilhac
- EID Méditerranée, 165 Avenue Paul-Rimbaud, 34184 Montpellier, France.
| | - Sébastien Boyer
- UMR-MIVEGEC, Institut de Recherche pour le Développement, 34394 Montpellier, France.
| | | | - Thierry Hance
- Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.
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Wiwanitkit V. Lessons learned from previous dengue outbreaks. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2014. [DOI: 10.1016/s2222-1808(14)60317-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Eisen L, Moore CG. Aedes (Stegomyia) aegypti in the continental United States: a vector at the cool margin of its geographic range. JOURNAL OF MEDICAL ENTOMOLOGY 2013; 50:467-78. [PMID: 23802440 DOI: 10.1603/me12245] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
After more than a half century without recognized local dengue outbreaks in the continental United States, there were recent outbreaks of autochthonous dengue in the southern parts of Texas (2004-2005) and Florida (2009-2011). This dengue reemergence has provoked interest in the extent of the future threat posed by the yellow fever mosquito, Aedes (Stegomyia) aegypti (L.), the primary vector of dengue and yellow fever viruses in urban settings, to human health in the continental United States. Ae. aegypti is an intriguing example of a vector species that not only occurs in the southernmost portions of the eastern United States today but also is incriminated as the likely primary vector in historical outbreaks of yellow fever as far north as New York, Philadelphia, and Boston, from the 1690s to the 1820s. For vector species with geographic ranges limited, in part, by low temperature and cool range margins occurring in the southern part of the continental United States, as is currently the case for Ae. aegypti, it is tempting to speculate that climate warming may result in a northward range expansion (similar to that seen for Ixodes tick vectors of Lyme borreliosis spirochetes in Scandinavia and southern Canada in recent decades). Although there is no doubt that climate conditions directly impact many aspects of the life history of Ae. aegypti, this mosquito also is closely linked to the human environment and directly influenced by the availability of water-holding containers for oviposition and larval development. Competition with other container-inhabiting mosquito species, particularly Aedes (Stegomyia) albopictus (Skuse), also may impact the presence and local abundance of Ae. aegypti. Field-based studies that focus solely on the impact of weather or climate factors on the presence and abundance of Ae. aegypti, including assessments of the potential impact of climate warming on the mosquito's future range and abundance, do not consider the potential confounding effects of socioeconomic factors or biological competitors for establishment and proliferation of Ae. aegypti. The results of such studies therefore should not be assumed to apply in areas with different socioeconomic conditions or composition of container-inhabiting mosquito species. For example, results from field-based studies at the high altitude cool margins for Ae. aegypti in Mexico's central highlands or the Andes in South America cannot be assumed to be directly applicable to geographic areas in the United States with comparable climate conditions. Unfortunately, we have a very poor understanding of how climatic drivers interact with the human landscape and biological competitors to impact establishment and proliferation of Ae. aegypti at the cool margin of its range in the continental United States. A first step toward assessing the future threat this mosquito poses to human health in the continental United States is to design and conduct studies across strategic climatic and socioeconomic gradients in the United States (including the U.S.-Mexico border area) to determine the permissiveness of the coupled natural and human environment for Ae. aegypti at the present time. This approach will require experimental studies and field surveys that focus specifically on climate conditions relevant to the continental United States. These studies also must include assessments of how the human landscape, particularly the impact of availability of larval developmental sites and the permissiveness of homes for mosquito intrusion, and the presence of other container-inhabiting mosquitoes that may compete with Ae. aegypti for larval habitat affects the ability of Ae. aegypti to establish and proliferate. Until we are armed with such knowledge, it is not possible to meaningfully assess the potential for climate warming to impact the proliferation potential for Ae. aegypti in the United States outside of the geographic areas where the mosquito already is firmly established, and even less so for dengue virus transmission and dengue disease in humans.
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Affiliation(s)
- Lars Eisen
- Department of Microbiology, Immunology and Pathology, Colorado State University, 3195 Rampart Road, Fort Collins, CO 80523, USA.
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