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Aldridge RL, Gibson S, Linthicum KJ. Aedes aegypti Controls AE. Aegypti: SIT and IIT-An Overview. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2024; 40:32-49. [PMID: 38427588 DOI: 10.2987/23-7154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
The sterile insect technique (SIT) and the incompatible insect technique (IIT) are emerging and potentially revolutionary tools for controlling Aedes aegypti (L.), a prominent worldwide mosquito vector threat to humans that is notoriously difficult to reduce or eliminate in intervention areas using traditional integrated vector management (IVM) approaches. Here we provide an overview of the discovery, development, and application of SIT and IIT to Ae. aegypti control, and innovations and advances in technology, including transgenics, that could elevate these techniques to a worldwide sustainable solution to Ae. aegypti when combined with other IVM practices.
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Diouf EG, Brévault T, Ndiaye S, Faye E, Chailleux A, Diatta P, Piou C. An agent-based model to simulate the boosted Sterile Insect Technique for fruit fly management. Ecol Modell 2022. [DOI: 10.1016/j.ecolmodel.2022.109951] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Ikegawa Y, Ito K, Himuro C, Honma A. Sterile males and females can synergistically suppress wild pests targeted by sterile insect technique. J Theor Biol 2021; 530:110878. [PMID: 34437884 DOI: 10.1016/j.jtbi.2021.110878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 06/17/2021] [Accepted: 08/19/2021] [Indexed: 10/20/2022]
Abstract
The sterile insect technique (SIT) involves periodically releasing artificially sterilized insects to inhibit normal mating between wild insect pests, ultimately resulting in the eradication of wild pest populations. It has often been discussed whether releasing either one sex, mainly males, of sterile insects (i.e., a unisexual release) can enhance the pest-control effect of the SIT more than releasing both sexes (i.e., a bisexual release). We constructed a mathematical model to examine the contribution of sterile males and females to the pest-control effect and the synergy between them. We consider that males seek out and court females in accord with their own female searching ability and preference, and that females subsequently choose one male from among males courting them in accordance with their own preference. Using this model, we compared the pest-control effect of bisexual and unisexual release, focusing on the difference in mating systems of the targeted insects. We showed that for swarm-type mating systems (with few courtship chances with higher encounter rates), bisexual release was the most effective, irrespective of the relative female searching ability between wild and sterile males. In this case, sterile females indirectly reduce wild females mating with either male by absorbing courtship from both wild and sterile males. By contrast, bisexual release is the most effective for scramble-type mating systems (more courtship chances with lower encounter rates) only when the female searching ability of sterile males is lower than that of wild males. In this case, sterile females absorb courtship from males with higher searching abilities. Therefore, the net impact of sterile females depends on the difference in sexual performance between wild and sterile males. Because the sexual performance of sterile insects is often degraded during the process of sterilization, we suggest that bisexual release can be a compatible measure to efficiently suppress wild pest populations.
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Affiliation(s)
- Yusuke Ikegawa
- Ryukyu Sankei Co. Ltd., 123 Maji, Naha, Okinawa 902-0072, Japan; Okinawa Prefectural Plant Protection Center, 123 Maji, Naha, Okinawa 902-0072, Japan; Graduate School of Agriculture, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami-gun, Okinawa 903-0213, Japan.
| | - Koichi Ito
- Department of Zoology, University of British Columbia, 4200-6270 University Blvd, Vancouver, B.C. V6T 1Z4, Canada
| | - Chihiro Himuro
- Ryukyu Sankei Co. Ltd., 123 Maji, Naha, Okinawa 902-0072, Japan; Okinawa Prefectural Plant Protection Center, 123 Maji, Naha, Okinawa 902-0072, Japan; Graduate School of Agriculture, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami-gun, Okinawa 903-0213, Japan
| | - Atsushi Honma
- Ryukyu Sankei Co. Ltd., 123 Maji, Naha, Okinawa 902-0072, Japan; Okinawa Prefectural Plant Protection Center, 123 Maji, Naha, Okinawa 902-0072, Japan; Graduate School of Agriculture, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami-gun, Okinawa 903-0213, Japan
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Li C, Wu X, Sheridan S, Lee J, Wang X, Yin J, Han J. Interaction of climate and socio-ecological environment drives the dengue outbreak in epidemic region of China. PLoS Negl Trop Dis 2021; 15:e0009761. [PMID: 34606516 PMCID: PMC8489715 DOI: 10.1371/journal.pntd.0009761] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 08/24/2021] [Indexed: 11/18/2022] Open
Abstract
Transmission of dengue virus is a complex process with interactions between virus, mosquitoes and humans, influenced by multiple factors simultaneously. Studies have examined the impact of climate or socio-ecological factors on dengue, or only analyzed the individual effects of each single factor on dengue transmission. However, little research has addressed the interactive effects by multiple factors on dengue incidence. This study uses the geographical detector method to investigate the interactive effect of climate and socio-ecological factors on dengue incidence from two perspectives: over a long-time series and during outbreak periods; and surmised on the possibility of dengue outbreaks in the future. Results suggest that the temperature plays a dominant role in the long-time series of dengue transmission, while socio-ecological factors have great explanatory power for dengue outbreaks. The interactive effect of any two factors is greater than the impact of single factor on dengue transmission, and the interactions of pairs of climate and socio-ecological factors have more significant impact on dengue. Increasing temperature and surge in travel could cause dengue outbreaks in the future. Based on these results, three recommendations are offered regarding the prevention of dengue outbreaks: mitigating the urban heat island effect, adjusting the time and frequency of vector control intervention, and providing targeted health education to travelers at the border points. This study hopes to provide meaningful clues and a scientific basis for policymakers regarding effective interventions against dengue transmission, even during outbreaks.
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Affiliation(s)
- Chenlu Li
- State Key Laboratory of Remote Sensing Science, College of Global Change and Earth System Science, Beijing Normal University, Beijing, China
| | - Xiaoxu Wu
- State Key Laboratory of Remote Sensing Science, College of Global Change and Earth System Science, Beijing Normal University, Beijing, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
- * E-mail:
| | - Scott Sheridan
- Department of Geography, Kent State University, Kent, Ohio, United States of America
| | - Jay Lee
- Department of Geography, Kent State University, Kent, Ohio, United States of America
- College of Environment and Planning, Henan University, Kaifeng, China
| | - Xiaofeng Wang
- Center for Disease Surveillance and Information Services, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Jie Yin
- State Key Laboratory of Remote Sensing Science, College of Global Change and Earth System Science, Beijing Normal University, Beijing, China
| | - Jiatong Han
- State Key Laboratory of Remote Sensing Science, College of Global Change and Earth System Science, Beijing Normal University, Beijing, China
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Douchet L, Haramboure M, Baldet T, L'Ambert G, Damiens D, Gouagna LC, Bouyer J, Labbé P, Tran A. Comparing sterile male releases and other methods for integrated control of the tiger mosquito in temperate and tropical climates. Sci Rep 2021; 11:7354. [PMID: 33795801 PMCID: PMC8016901 DOI: 10.1038/s41598-021-86798-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 03/19/2021] [Indexed: 11/09/2022] Open
Abstract
The expansion of mosquito species worldwide is creating a powerful network for the spread of arboviruses. In addition to the destruction of breeding sites (prevention) and mass trapping, methods based on the sterile insect technique (SIT), the autodissemination of pyriproxyfen (ADT), and a fusion of elements from both of these known as boosted SIT (BSIT), are being developed to meet the urgent need for effective vector control. However, the comparative potential of these methods has yet to be explored in different environments. This is needed to propose and integrate informed guidelines into sustainable mosquito management plans. We extended a weather-dependent model of Aedes albopictus population dynamics to assess the effectiveness of these different vector control methods, alone or in combination, in a tropical (Reunion island, southwest Indian Ocean) and a temperate (Montpellier area, southern France) climate. Our results confirm the potential efficiency of SIT in temperate climates when performed early in the year (mid-March for northern hemisphere). In such a climate, the timing of the vector control action was the key factor in its success. In tropical climates, the potential of the combination of methods becomes more relevant. BSIT and the combination of ADT with SIT were twice as effective compared to the use of SIT alone.
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Affiliation(s)
- Léa Douchet
- CIRAD, UMR ASTRE, 97491, Sainte-Clotilde, Reunion, France
- ASTRE, CIRAD, INRAE, Univ Montpellier, Montpellier, France
| | - Marion Haramboure
- CIRAD, UMR ASTRE, 97491, Sainte-Clotilde, Reunion, France.
- ASTRE, CIRAD, INRAE, Univ Montpellier, Montpellier, France.
- ISEM, CNRS, IRD, EPHE, Université de Montpellier, Montpellier, France.
- TETIS, AgroParisTech, CIRAD, CNRS, INRAE, Univ Montpellier, Montpellier, France.
| | - Thierry Baldet
- CIRAD, UMR ASTRE, 97491, Sainte-Clotilde, Reunion, France
- ASTRE, CIRAD, INRAE, Univ Montpellier, Montpellier, France
| | - Gregory L'Ambert
- Department of Research and Development, EID Méditerranée, Montpellier, France
| | - David Damiens
- IRD, CNRS-UM-IRD, UMR MIVEGEC, Montpellier, Reunion, France
- IRD/GIP CYROI, Sainte-Clotilde, Reunion, France
| | - Louis Clément Gouagna
- IRD, CNRS-UM-IRD, UMR MIVEGEC, Montpellier, Reunion, France
- IRD/GIP CYROI, Sainte-Clotilde, Reunion, France
| | - Jeremy Bouyer
- ASTRE, CIRAD, INRAE, Univ Montpellier, Montpellier, France
- CIRAD, UMR ASTRE, 34398, Montpellier, France
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, 1400, Vienna, Austria
- CIRAD, UMR ASTRE, 97410, Saint-Pierre, Reunion, France
| | - Pierrick Labbé
- ISEM, CNRS, IRD, EPHE, Université de Montpellier, Montpellier, France
| | - Annelise Tran
- CIRAD, UMR ASTRE, 97491, Sainte-Clotilde, Reunion, France
- ASTRE, CIRAD, INRAE, Univ Montpellier, Montpellier, France
- TETIS, AgroParisTech, CIRAD, CNRS, INRAE, Univ Montpellier, Montpellier, France
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Modelling the control of Aedes albopictus mosquitoes based on sterile males release techniques in a tropical environment. Ecol Modell 2020. [DOI: 10.1016/j.ecolmodel.2020.109002] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Multerer L, Smith T, Chitnis N. Modeling the impact of sterile males on an Aedes aegypti population with optimal control. Math Biosci 2019; 311:91-102. [PMID: 30857942 DOI: 10.1016/j.mbs.2019.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 03/04/2019] [Accepted: 03/05/2019] [Indexed: 11/29/2022]
Abstract
We use partial differential equations to describe the dynamics of an Aedes aegypti mosquito population on an island, and the effects of a sterile male release. The model includes mosquito movement and an Allee effect to capture extinction events. We apply optimal control theory to identify the release strategy that eliminates the mosquitoes most rapidly, conditional on a limited availability of sterile males. The optimal solution for a single location is to initially release a substantial number of mosquitoes and to subsequently release fewer sterile males proportionally to the decreasing female population. The optimal solution for the whole island is intractable given a constraint on the total daily release of sterile males. The best approximation to the spatial optimal control strategy is to focus on the high mosquito density areas first and then move outwards (in both directions along the periphery of the island), until all areas have been covered, retaining throughout sufficient release intensity to prevent reintroduction in the already cleared areas.
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Affiliation(s)
- Lea Multerer
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland.
| | - Thomas Smith
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland.
| | - Nakul Chitnis
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland.
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Facchinelli L, North AR, Collins CM, Menichelli M, Persampieri T, Bucci A, Spaccapelo R, Crisanti A, Benedict MQ. Large-cage assessment of a transgenic sex-ratio distortion strain on populations of an African malaria vector. Parasit Vectors 2019; 12:70. [PMID: 30728060 PMCID: PMC6366042 DOI: 10.1186/s13071-019-3289-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 01/03/2019] [Indexed: 12/25/2022] Open
Abstract
Background Novel transgenic mosquito control methods require progressively more realistic evaluation. The goal of this study was to determine the effect of a transgene that causes a male-bias sex ratio on Anopheles gambiae target populations in large insectary cages. Methods Life history characteristics of Anopheles gambiae wild type and Ag(PMB)1 (aka gfp124L-2) transgenic mosquitoes, whose progeny are 95% male, were measured in order to parameterize predictive population models. Ag(PMB)1 males were then introduced at two ratios into large insectary cages containing target wild type populations with stable age distributions and densities. The predicted proportion of females and those observed in the large cages were compared. A related model was then used to predict effects of male releases on wild mosquitoes in a west African village. Results The frequency of transgenic mosquitoes in target populations reached an average of 0.44 ± 0.02 and 0.56 ± 0.02 after 6 weeks in the 1:1 and in the 3:1 release ratio treatments (transgenic male:wild male) respectively. Transgenic males caused sex-ratio distortion of 73% and 80% males in the 1:1 and 3:1 treatments, respectively. The number of eggs laid in the transgenic treatments declined as the experiment progressed, with a steeper decline in the 3:1 than in the 1:1 releases. The results of the experiment are partially consistent with predictions of the model; effect size and variability did not conform to the model in two out of three trials, effect size was over-estimated by the model and variability was greater than anticipated, possibly because of sampling effects in restocking. The model estimating the effects of hypothetical releases on the mosquito population of a West African village demonstrated that releases could significantly reduce the number of females in the wild population. The interval of releases is not expected to have a strong effect. Conclusions The biological data produced to parameterize the model, the model itself, and the results of the experiments are components of a system to evaluate and predict the performance of transgenic mosquitoes. Together these suggest that the Ag(PMB)1 strain has the potential to be useful for reversible population suppression while this novel field develops.
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Affiliation(s)
- Luca Facchinelli
- Department of Experimental Medicine, University of Perugia, Perugia, Italy.,Present address: Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Ace R North
- Department of Zoology, University of Oxford, New Radcliffe House, Woodstock Road, Oxford, OX2 6GG, UK
| | - C Matilda Collins
- Centre for Environmental Policy, Imperial College London, 16-18 Princes Gardens, London, SW7 1NE, UK
| | - Miriam Menichelli
- Polo di Genomica Genetica e Biologia, Via mazzieri 3, 05100, Terni, Italy
| | - Tania Persampieri
- Polo di Genomica Genetica e Biologia, Via mazzieri 3, 05100, Terni, Italy
| | - Alessandro Bucci
- Polo di Genomica Genetica e Biologia, Via mazzieri 3, 05100, Terni, Italy
| | - Roberta Spaccapelo
- Department of Experimental Medicine, University of Perugia, 06132, Perugia, Italy
| | - Andrea Crisanti
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building Imperial College Road South Kensington, London, SW7 2AZ, UK
| | - Mark Q Benedict
- Centers for Disease Control and Prevention (CDC), 1600 Clifton Road, Atlanta, GA, 30329, USA.
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Mishra A, Ambrosio B, Gakkhar S, Aziz-Alaoui MA. A network model for control of dengue epidemic using sterile insect technique. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2018; 15:441-460. [PMID: 29161844 DOI: 10.3934/mbe.2018020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this paper, a network model has been proposed to control dengue disease transmission considering host-vector dynamics in n patches. The control of mosquitoes is performed by SIT. In SIT, the male insects are sterilized in the laboratory and released into the environment to control the number of offsprings. The basic reproduction number has been computed. The existence and stability of various states have been discussed. The bifurcation diagram has been plotted to show the existence and stability regions of disease-free and endemic states for an isolated patch. The critical level of sterile male mosquitoes has been obtained for the control of disease. The basic reproduction number for n patch network model has been computed. It is evident from numerical simulations that SIT control in one patch may control the disease in the network having two/three patches with suitable coupling among them.
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Affiliation(s)
- Arti Mishra
- Department of Mathematics, Indian Institute of Technology Roorkee, Uttarakhand 247667, India
| | - Benjamin Ambrosio
- Normandie Univ, UNIHAVRE, LMAH, FR-CNRS-3335, ISCN, 76600 Le Havre, France
| | - Sunita Gakkhar
- Department of Mathematics, Indian Institute of Technology Roorkee, Uttarakhand 247667, India
| | - M A Aziz-Alaoui
- Normandie Univ, UNIHAVRE, LMAH, FR-CNRS-3335, ISCN, 76600 Le Havre, France
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Ikegawa Y, Himuro C. Limited mobility of target pests crucially lowers controllability when sterile insect releases are spatiotemporally biased. J Theor Biol 2017; 421:93-100. [PMID: 28363862 DOI: 10.1016/j.jtbi.2017.03.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 03/21/2017] [Accepted: 03/27/2017] [Indexed: 11/25/2022]
Abstract
The sterile insect technique (SIT) is a genetic pest control method wherein mass-reared sterile insects are periodically released into the wild, thereby impeding the successful reproduction of fertile pests. In Okinawa Prefecture, Japan, the SIT has been implemented to eradicate the West Indian sweet potato weevil Euscepes postfasciatus (Fairmaire), which is a flightless agricultural pest of sweet potatoes. It is known that E. postfasciatus is much less mobile than other insects to which the SIT has been applied. However, previous theoretical studies have rarely examined effects of low mobility of target pests and variation in the spatiotemporal evenness of sterile insect releases. To theoretically examine the effects of spatiotemporal evenness on the regional eradication of less mobile pests, we constructed a simple two-patch population model comprised of a pest and sterile insect moving between two habitats, and numerically simulated different release strategies (varying the number of released sterile insects and release intervals). We found that spatially biased releases allowed the pest to spatially escape from the sterile insect, and thus intensively lowered its controllability. However, we showed that the temporally counterbalancing spatially biased releases by swapping the number of released insects in the two habitats at every release (called temporal balancing) could greatly mitigate this negative effect and promote the controllability. We also showed that the negative effect of spatiotemporally biased releases was a result of the limited mobility of the target insect. Although directed dispersal of the insects in response to habitats of differing quality could lower the controllability in the more productive habitat, the temporal balancing could promote and eventually maximize the controllability as released insects increased.
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Affiliation(s)
- Yusuke Ikegawa
- Ryukyu Sankei Co. Ltd., 123 Maji, Naha, Okinawa, 902-0072, Japan; Okinawa Prefectural Plant Protection Center, 123 Maji, Naha, Okinawa, 902-0072, Japan; Graduate School of Agriculture, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami-gun, Okinawa, 903-0213, Japan.
| | - Chihiro Himuro
- Ryukyu Sankei Co. Ltd., 123 Maji, Naha, Okinawa, 902-0072, Japan; Okinawa Prefectural Plant Protection Center, 123 Maji, Naha, Okinawa, 902-0072, Japan; Graduate School of Agriculture, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami-gun, Okinawa, 903-0213, Japan
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Hendron RWS, Bonsall MB. The interplay of vaccination and vector control on small dengue networks. J Theor Biol 2016; 407:349-361. [PMID: 27457093 PMCID: PMC5016021 DOI: 10.1016/j.jtbi.2016.07.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 06/18/2016] [Accepted: 07/21/2016] [Indexed: 01/03/2023]
Abstract
Dengue fever is a major public health issue affecting billions of people in over 100 countries across the globe. This challenge is growing as the invasive mosquito vectors, Aedes aegypti and Aedes albopictus, expand their distributions and increase their population sizes. Hence there is an increasing need to devise effective control methods that can contain dengue outbreaks. Here we construct an epidemiological model for virus transmission between vectors and hosts on a network of host populations distributed among city and town patches, and investigate disease control through vaccination and vector control using variants of the sterile insect technique (SIT). Analysis of the basic reproductive number and simulations indicate that host movement across this small network influences the severity of epidemics. Both vaccination and vector control strategies are investigated as methods of disease containment and our results indicate that these controls can be made more effective with mixed strategy solutions. We predict that reduced lethality through poor SIT methods or imperfectly efficacious vaccines will impact efforts to control disease spread. In particular, weakly efficacious vaccination strategies against multiple virus serotype diversity may be counter productive to disease control efforts. Even so, failings of one method may be mitigated by supplementing it with an alternative control strategy. Generally, our network approach encourages decision making to consider connected populations, to emphasise that successful control methods must effectively suppress dengue epidemics at this landscape scale.
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Affiliation(s)
- Ross-William S Hendron
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK; St. Peter's College, New Inn Hall Street, Oxford OX1 2DL, UK
| | - Michael B Bonsall
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK; St. Peter's College, New Inn Hall Street, Oxford OX1 2DL, UK.
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