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Oliva CF, Vreysen MJB, Dupé S, Lees RS, Gilles JRL, Gouagna LC, Chhem R. Current status and future challenges for controlling malaria with the sterile insect technique: technical and social perspectives. Acta Trop 2014; 132 Suppl:S130-9. [PMID: 24295892 DOI: 10.1016/j.actatropica.2013.11.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 11/19/2013] [Accepted: 11/23/2013] [Indexed: 12/23/2022]
Abstract
The intolerable burden of malaria, when faced with high levels of drug resistance, increasing insecticide resistance and meagre resources at the national level, remains a great public health challenge to governments and the research/control community. Efficient control methods against the vectors of malaria are desperately needed. Control strategies for malaria that integrate the transfer of sterile sperm by released males to wild virgin females with other control tactics are currently being developed, and optimised mass-rearing, irradiation and release techniques are being validated in several field sites. However, the success of this strategy as part of wider pest control or health management programmes strongly depends on gaining public understanding and acceptance. Here we attempt to review what progress has been made and the remaining challenges surrounding the use of the sterile insect technique against malaria from technical and social perspectives.
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Affiliation(s)
- Clelia F Oliva
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria; MIVEGEC (IRD 224-CNRS 5290-UM1-UM2) Montpellier, Montpellier, France; Centre de Recherche et de Veille sur les Maladies Emergentes dans l'Océan Indien, 2 rue Maxime Rivière, 97490 Sainte Clotilde, La Réunion, France.
| | - Marc J B Vreysen
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria.
| | - Sandrine Dupé
- Centre de Recherche et de Veille sur les Maladies Emergentes dans l'Océan Indien, 2 rue Maxime Rivière, 97490 Sainte Clotilde, La Réunion, France; Langues, textes et communication dans les espaces Créolophones et Francophones (EA 4549), Université de La Réunion, Saint Denis, France; Eco-anthropologie et Ethnobiologie (UMR 7206), Muséum National d'Histoire Naturelle, Paris, France.
| | - Rosemary S Lees
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria.
| | - Jeremie R L Gilles
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria.
| | - Louis-Clement Gouagna
- MIVEGEC (IRD 224-CNRS 5290-UM1-UM2) Montpellier, Montpellier, France; Centre de Recherche et de Veille sur les Maladies Emergentes dans l'Océan Indien, 2 rue Maxime Rivière, 97490 Sainte Clotilde, La Réunion, France.
| | - Rethy Chhem
- Division of Human Health, Department of Nuclear Science and Applications, International Atomic Energy Agency, Vienna, Austria; Institute of the History, Philosophy and Ethics of Medicine, Ulm University, Ulm, Germany.
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Kumar A, Chery L, Biswas C, Dubhashi N, Dutta P, Dua VK, Kacchap M, Kakati S, Khandeparkar A, Kour D, Mahajan SN, Maji A, Majumder P, Mohanta J, Mohapatra PK, Narayanasamy K, Roy K, Shastri J, Valecha N, Vikash R, Wani R, White J, Rathod PK. Malaria in South Asia: prevalence and control. Acta Trop 2012; 121:246-55. [PMID: 22248528 DOI: 10.1016/j.actatropica.2012.01.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 01/02/2012] [Accepted: 01/02/2012] [Indexed: 11/28/2022]
Abstract
The "Malaria Evolution in South Asia" (MESA) program project is an International Center of Excellence for Malaria Research (ICEMR) sponsored by the US National Institutes of Health. This US-India collaborative program will study the origin of genetic diversity of malaria parasites and their selection on the Indian subcontinent. This knowledge should contribute to a better understanding of unexpected disease outbreaks and unpredictable disease presentations from Plasmodium falciparum and Plasmodium vivax infections. In this first of two reviews, we highlight malaria prevalence in India. In particular, we draw attention to variations in distribution of different human-parasites and different vectors, variation in drug resistance traits, and multiple forms of clinical presentations. Uneven malaria severity in India is often attributed to large discrepancies in health care accessibility as well as human migrations within the country and across neighboring borders. Poor access to health care goes hand in hand with poor reporting from some of the same areas, combining to possibly distort disease prevalence and death from malaria in some parts of India. Corrections are underway in the form of increased resources for disease control, greater engagement of village-level health workers for early diagnosis and treatment, and possibly new public-private partnerships activities accompanying traditional national malaria control programs in the most severely affected areas. A second accompanying review raises the possibility that, beyond uneven health care, evolutionary pressures may alter malaria parasites in ways that contribute to severe disease in India, particularly in the NE corridor of India bordering Myanmar Narayanasamy et al., 2012.
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Affiliation(s)
- Ashwani Kumar
- National Institute of Malaria Research, Panaji, Goa, India
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3
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Malaria vector control: from past to future. Parasitol Res 2011; 108:757-79. [PMID: 21229263 DOI: 10.1007/s00436-010-2232-0] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Accepted: 10/06/2010] [Indexed: 01/17/2023]
Abstract
Malaria is one of the most common vector-borne diseases widespread in the tropical and subtropical regions. Despite considerable success of malaria control programs in the past, malaria still continues as a major public health problem in several countries. Vector control is an essential part for reducing malaria transmission and became less effective in recent years, due to many technical and administrative reasons, including poor or no adoption of alternative tools. Of the different strategies available for vector control, the most successful are indoor residual spraying and insecticide-treated nets (ITNs), including long-lasting ITNs and materials. Earlier DDT spray has shown spectacular success in decimating disease vectors but resulted in development of insecticide resistance, and to control the resistant mosquitoes, organophosphates, carbamates, and synthetic pyrethroids were introduced in indoor residual spraying with needed success but subsequently resulted in the development of widespread multiple insecticide resistance in vectors. Vector control in many countries still use insecticides in the absence of viable alternatives. Few developments for vector control, using ovitraps, space spray, biological control agents, etc., were encouraging when used in limited scale. Likewise, recent introduction of safer vector control agents, such as insect growth regulators, biocontrol agents, and natural plant products have yet to gain the needed scale of utility for vector control. Bacterial pesticides are promising and are effective in many countries. Environmental management has shown sufficient promise for vector control and disease management but still needs advocacy for inter-sectoral coordination and sometimes are very work-intensive. The more recent genetic manipulation and sterile insect techniques are under development and consideration for use in routine vector control and for these, standardized procedures and methods are available but need thorough understanding of biology, ethical considerations, and sufficiently trained manpower for implementation being technically intensive methods. All the methods mentioned in the review that are being implemented or proposed for implementation needs effective inter-sectoral coordination and community participation. The latest strategy is evolution-proof insecticides that include fungal biopesticides, Wolbachia, and Denso virus that essentially manipulate the life cycle of the mosquitoes were found effective but needs more research. However, for effective vector control, integrated vector management methods, involving use of combination of effective tools, is needed and is also suggested by Global Malaria Control Strategy. This review article raises issues associated with the present-day vector control strategies and state opportunities with a focus on ongoing research and recent advances to enable to sustain the gains achieved so far.
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Chandra G, Bhattacharjee I, Chatterjee S. A review on Anopheles subpictus Grassi--a biological vector. Acta Trop 2010; 115:142-54. [PMID: 20153284 DOI: 10.1016/j.actatropica.2010.02.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 01/29/2010] [Accepted: 02/05/2010] [Indexed: 11/17/2022]
Abstract
Anopheles subpictus is a complex of four isomorphic sibling species A, B, C and D and is recognized as a primary vector of malaria, a disease of great socio-economic importance, in Australasian Zone, Celebes, Portuguese Timor and South East Asia and a secondary vector in Sri Lanka. This species is also a vector of some helminth and arboviruses. This species has been reported so far from nineteen countries of the Oriental and Australasian Zones. An. subpictus complex is the most abundant anopheline in most parts of the Indian subcontinent, with a widespread distribution eastwards and southwards to Papua New Guinea, westwards to Iran and northwards to China. Resistance to insecticide is alarming in many parts of the world. Different aspects of this important mosquito species including attempts related to its control have been discussed which will be highly useful to carry out further research.
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Affiliation(s)
- Goutam Chandra
- Department of Zoology, Parasitology Laboratory, The University of Burdwan, Burdwan, West Bengal 713104, India.
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Dash AP, Valecha N, Anvikar AR, Kumar A. Malaria in India: challenges and opportunities. J Biosci 2009; 33:583-92. [PMID: 19208983 DOI: 10.1007/s12038-008-0076-x] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
India contributes about 70% of malaria in the South East Asian Region of WHO. Although annually India reports about two million cases and 1000 deaths attributable to malaria,there is an increasing trend in the proportion of Plasmodium falciparum as the agent. There exists heterogeneity and variability in the risk of malaria transmission between and within the states of the country as many ecotypes/paradigms of malaria have been recognized. The pattern of clinical presentation of severe malaria has also changed and while multi-organ failure is more frequently observed in falciparum malaria, there are reports of vivax malaria presenting with severe manifestations. The high burden populations are ethnic tribes living in the forested pockets of the states like Orissa, Jharkhand, Madhya Pradesh, Chhattisgarh and the North Eastern states which contribute bulk of morbidity and mortality due to malaria in the country. Drug resistance,insecticide resistance,lack of knowledge of actual disease burden along with new paradigms of malaria pose a challenge for malaria control in the country. Considering the existing gaps in reported and estimated morbidity and mortality, need for estimation of true burden of malaria has been stressed. Administrative, financial,technical and operational challenges faced by the national programme have been elucidated. Approaches and priorities that may be helpful in tackling serious issues confronting malaria programme have been outlined.
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Affiliation(s)
- A P Dash
- National Institute of Malaria Research, 22 Sham Nath Marg, Delhi 110 054, India.
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Barik T, Sahu B, Swain V. A review on Anopheles culicifacies: from bionomics to control with special reference to Indian subcontinent. Acta Trop 2009; 109:87-97. [PMID: 19000647 DOI: 10.1016/j.actatropica.2008.09.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2008] [Revised: 08/07/2008] [Accepted: 09/26/2008] [Indexed: 10/21/2022]
Abstract
Anopheles culicifacies, is a complex of five isomorphic sibling species A, B, C, D and E and is considered to be the major malaria vector in the Indian subcontinent. Despite numerous studies, it is difficult to have a global view of the ecological and bionomical characteristics of the individual sibling species, as different identification methods have been used. Major biological and ecological trends such as the high plasticity of behaviour and the sympatry of species are addressed. In spite of the availability of rapid molecular identification tools, we still lack important information concerning the biological characteristics of each sibling species. Resistance to insecticide is alarming as it has developed quadruple resistance in two states of India. An intensified and appropriate intervention measure to interrupt transmission is the call of the day. The authors focus on (1) reviewing the vectorial aspects of An. culicifacies (2) discussing recently published data on bionomics of each sibling species, (3) identifying lacunae in the understanding of the Culicifacies complex, and (4) exploring the possibility of proper control measures. Our understanding of the bionomics of all the five sibling species would certainly help, keeping in mind the climatic changes we are to face in the next few years.
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Goswami G, Raghavendra K, Nanda N, Gakhar SK, Subbarao SK. PCR-RFLP of mitochondrial cytochrome oxidase subunit II and ITS2 of ribosomal DNA: markers for the identification of members of the Anopheles culicifacies complex (Diptera: Culicidae). Acta Trop 2005; 95:92-9. [PMID: 15967406 DOI: 10.1016/j.actatropica.2005.04.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2003] [Revised: 04/10/2005] [Accepted: 04/18/2005] [Indexed: 11/24/2022]
Abstract
Anopheles culicifacies Giles is a complex of five sibling species, provisionally designated as species A, B, C, D and E. Species A, C, D and E are vectors of malaria in India. Species A, B, C and D can be identified by polytene chromosome examination except in areas where species B and E are sympatric. Species B and E share the same configuration of the polytene chromosomes but can be differentiated by examining the mitotic chromosomes of F(1) progeny from field collection. Further, polytene chromosome examination method requires the mosquitoes to be at the semigravid stage, which limits on use of this method to a very small proportion of the population. The present study investigated whether the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method can be used to differentiate the members of this complex. Complete ITS2 region along with part of the 5.8S and 28S rDNA sequences (512 bp) and the mitochondrial cytochrome oxidase II (530 bp) were amplified and digested with different restriction endonucleases. The Alu I digest of the COII amplicon and Rsa I digest of the ITS2 amplicon could distinguish two categories: species A and D forming one category and species B, C and E forming another. Further, Dde I digestion of the COII amplicon could distinguish species E from species B and C within the latter category. The PCR-RFLP techniques developed in this study can be applied to areas where species A and B and species B and E are sympatric.
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Affiliation(s)
- Geeta Goswami
- Department of Biosciences, Maharishi Dayanand University, Rohtak, Haryana, India.
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Chaudhry S, Gupta S, Chhilar JS. Salivary polytene chromosome mapping ofAnopheles(Cellia)subpictusGrassi (Culicidae: Diptera). Genome 2005; 48:241-6. [PMID: 15838546 DOI: 10.1139/g04-120] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
With the introduction of molecular taxonomy of mosquitoes, polytene chromosome maps have become indispensable as standard references for locating genes, puffs, and inversion breakpoints of unique DNA sequences. We present a line map and a photomap of the salivary polytene chromosomes of Anopheles (Cellia) subpictus Grassi, an important emerging vector of malaria in India. In addition, we discuss the nature of this species complex consisting of sibling species A, B, C, and D. The comparative study is in relevance to the X chromosome heterozygous inversion differences between 2 allopatric populations of the species and the recognition of 4 X-chromosome inversion genotypes viz: species A–X+a+b, B–Xab, C–Xa+band D–X+ab.Key words: Anopheles subpictus, polytene chromosome map.
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Affiliation(s)
- S Chaudhry
- Mosquito Cytogenetics Unit, Department of Zoology, Panjab University, Chandigarh, India.
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Hemingway J, Bates I. Malaria: past problems and future prospects. After more than a decade of neglect, malaria is finally black on the agenda for both biomedical research and public health politics. EMBO Rep 2003; 4 Spec No:S29-31. [PMID: 12789402 PMCID: PMC1326433 DOI: 10.1038/sj.embor.embor841] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
After more than a decade of neglect, malaria is finally back on the agenda for both biomedical research and public health politics
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Affiliation(s)
- Janet Hemingway
- Janet Hemingway and Imelda Bates are at the Liverpool School of Tropical Medicine, Liverpool, UK.
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Croft A. Extracts from "Clinical Evidence". Malaria: prevention in travellers. BMJ (CLINICAL RESEARCH ED.) 2000; 321:154-60. [PMID: 10894695 PMCID: PMC1118163 DOI: 10.1136/bmj.321.7254.154] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
DEFINITION Malaria is caused by a protozoan infection of red blood cells with one of four species of the genus plasmodium: P falciparum, P vivax, P ovale, or P malariae. Clinically, malaria may present in different ways, but it is usually characterised by fever (which may be swinging), tachycardia, rigors, and sweating. Anaemia, hepatosplenomegaly, cerebral involvement, renal failure, and shock may occur. INCIDENCE/PREVALENCE: Each year there are 300-500 million clinical cases of malaria. About 40% of the world's population is at risk of acquiring the disease. Each year 25-30 million people from non-tropical countries visit areas in which malaria is endemic, of whom between 10,000 and 30,000 contract malaria. AETIOLOGY/RISK FACTORS: Malaria is mainly a rural disease, requiring standing water nearby. It is transmitted by bites from infected female anopheline mosquitoes, mainly at dusk and during the night. In cities, mosquito bites are usually from female culicene mosquitoes, which are not vectors of malaria. Malaria is resurgent in most tropical countries and the risk to travellers is increasing. PROGNOSIS Ninety per cent of travellers who contract malaria do not become ill until after they return home. "Imported malaria" is easily treated if diagnosed promptly, and it follows a serious course in only about 12% of people. The most severe form of the disease is cerebral malaria, with a case fatality rate in adult travellers of 2-6%, mainly because of delays in diagnosis. AIMS To reduce the risk of infection; to prevent illness and death. OUTCOMES Rates of malarial illness and death, and adverse effects of treatment. Proxy measures include number of mosquito bites and number of mosquitoes in indoor areas. We found limited evidence linking number of mosquito bites and risk of malaria. METHODS Clinical Evidence search and appraisal in November 1999. We reviewed all identified systematic reviews and randomised controlled trials (RCTs).
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Affiliation(s)
- A Croft
- Ministry of Defence, London SW1A 2HB.
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Killeen GF, McKenzie FE, Foy BD, Schieffelin C, Billingsley PF, Beier JC. The potential impact of integrated malaria transmission control on entomologic inoculation rate in highly endemic areas. Am J Trop Med Hyg 2000; 62:545-51. [PMID: 11289662 PMCID: PMC2500225 DOI: 10.4269/ajtmh.2000.62.545] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We have used a relatively simple but accurate model for predicting the impact of integrated transmission control on the malaria entomologic inoculation rate (EIR) at four endemic sites from across sub-Saharan Africa and the southwest Pacific. The simulated campaign incorporated modestly effective vaccine coverage, bed net use, and larval control. The results indicate that such campaigns would reduce EIRs at all four sites by 30- to 50-fold. Even without the vaccine, 15- to 25-fold reductions of EIR were predicted, implying that integrated control with a few modestly effective tools can meaningfully reduce malaria transmission in a range of endemic settings. The model accurately predicts the effects of bed nets and indoor spraying and demonstrates that they are the most effective tools available for reducing EIR. However, the impact of domestic adult vector control is amplified by measures for reducing the rate of emergence of vectors or the level of infectiousness of the human reservoir. We conclude that available tools, including currently neglected methods for larval control, can reduce malaria transmission intensity enough to alleviate mortality. Integrated control programs should be implemented to the fullest extent possible, even in areas of intense transmission, using simple models as decision-making tools. However, we also conclude that to eliminate malaria in many areas of intense transmission is beyond the scope of methods which developing nations can currently afford. New, cost-effective, practical tools are needed if malaria is ever to be eliminated from highly endemic areas.
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Affiliation(s)
- G F Killeen
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Center for Infectious Diseases, Tulane University Health Sciences Center, New Orleans, Louisiana 70112-2824, USA
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Killeen GF, McKenzie FE, Foy BD, Schieffelin C, Billingsley PF, Beier JC. A simplified model for predicting malaria entomologic inoculation rates based on entomologic and parasitologic parameters relevant to control. Am J Trop Med Hyg 2000; 62:535-44. [PMID: 11289661 PMCID: PMC2483339 DOI: 10.4269/ajtmh.2000.62.535] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Malaria transmission intensity is modeled from the starting perspective of individual vector mosquitoes and is expressed directly as the entomologic inoculation rate (EIR). The potential of individual mosquitoes to transmit malaria during their lifetime is presented graphically as a function of their feeding cycle length and survival, human biting preferences, and the parasite sporogonic incubation period. The EIR is then calculated as the product of 1) the potential of individual vectors to transmit malaria during their lifetime, 2) vector emergence rate relative to human population size, and 3) the infectiousness of the human population to vectors. Thus, impacts on more than one of these parameters will amplify each other's effects. The EIRs transmitted by the dominant vector species at four malaria-endemic sites from Papua New Guinea, Tanzania, and Nigeria were predicted using field measurements of these characteristics together with human biting rate and human reservoir infectiousness. This model predicted EIRs (+/- SD) that are 1.13 +/- 0.37 (range = 0.84-1.59) times those measured in the field. For these four sites, mosquito emergence rate and lifetime transmission potential were more important determinants of the EIR than human reservoir infectiousness. This model and the input parameters from the four sites allow the potential impacts of various control measures on malaria transmission intensity to be tested under a range of endemic conditions. The model has potential applications for the development and implementation of transmission control measures and for public health education.
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Affiliation(s)
- G F Killeen
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Center for Infectious Diseases, Tulane University Health Sciences Center, New Orleans, Louisiana 70112-2824, USA
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Willadsen P. Immunological control of ectoparasites: past achievements and future research priorities. GENETIC ANALYSIS : BIOMOLECULAR ENGINEERING 1999; 15:131-7. [PMID: 10596752 DOI: 10.1016/s1050-3862(99)00016-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recombinant vaccines are available for the control of the tick Boophilus microplus, while progress has been made in the development of vaccines against Lucilia cuprina and Chrysomya bezziana. Literature suggests that the control of other ectoparasites is feasible, either through the duplication in a vaccine of naturally acquired immunity or through 'concealed' antigen vaccines. Major deficiencies in our current knowledge however point to possible research opportunities for the future. The identification of protective antigens from all species is proceeding slowly, particularly for the antigens of naturally acquired immunity. Our capacity to produce effective recombinant antigens has progressed greatly, though there remains a major difficulty where some or all of the protective effect is due to immunogenic oligosaccharide. Our understanding of protective mechanisms is limited. The delivery of the appropriate immunological response remains difficult. Nevertheless, some of the most critical areas of ignorance are in basic biological issues: factors which affect the susceptibility of particular pest species to immunological attack and the implications of vaccine-induced effects for pest and disease control under field conditions. Increasingly too, effective pest control is likely to demand the integration of a variety of control technologies. The study of this integration is in its infancy.
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Affiliation(s)
- P Willadsen
- CSIRO Tropical Agriculture, Long Pocket Laboratories, Indooroopilly, Qld, Australia.
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