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The application of the Sterile Insect Technique (SIT) in area-wide integrated pest management (AW-IPM) programmes continues to increase. However, programme efficiency can still be considerably enhanced when certain components of the technology are improved, such as the development of improved strains for mass rearing and release. These include strains that (1) produce only male insects for sterilization and release and (2) carry easily identifiable markers to identify released sterile insects in the field. Using both classical and modern biotechnology techniques, key insect pests are targeted, where SIT programmes are being implemented. The pests include mosquitoes, the Mexican fruit fly, the codling moth, the oriental fruit fly and the pink bollworm. This special issue summarizes the results of research efforts aimed at the development and evaluation of new strains to a level where a decision can be made as to their suitability for use in large scale SIT programmes. Major beneficiaries will be operational AW-IPM programmes that apply the SIT against major insect pests.

If appropriately applied, biological control offers one of the most promising, environmentally sound, and sustainable control tactics for arthropod pests and weeds for application as part of an integrated pest management (IPM) approach. Public support for biological control as one of the preferred methods of managing non-indigenous and indigenous pests is increasing in many countries. An FAO/IAEA Coordinated Research Project (CRP) addressed constraints related to costly production systems for biological control agents, and the presence of accompanying pest organisms during their shipment. These constraints can be alleviated using nuclear techniques such as ionizing radiation or X-rays to reduce production and handling costs (e.g., by expanding the period of host suitability, increasing shelf life, avoiding unnecessary sorting steps before shipment, etc.), and to eliminate the risk of shipping fertile host or prey pest individuals or other hitchhiking pests. These nuclear techniques can also help ...

Genetic modification (GM) of mosquitoes (which renders them genetically modified organisms, GMOs) offers opportunities for controlling malaria. Transgenic strains of mosquitoes have been developed and evaluation of these to 1) replace or suppress wild vector populations and 2) reduce transmission and deliver public health gains are an imminent prospect. The transition of this approach from confined laboratory settings to open field trials in disease-endemic countries (DECs) is a staged process that aims to maximize the likelihood of epidemiologic benefits while minimizing potential pitfalls during implementation. Unlike conventional approaches to vector control, application of GM mosquitoes will face contrasting expectations of multiple stakeholders, the management of which will prove critical to safeguard support and avoid antagonism, so that potential public health benefits can be fully evaluated. Inclusion of key stakeholders in decision-making processes, transfer of problem-ownership to DECs, and increased support from the wider malaria research community are important prerequisites for this. It is argued that the many developments in this field require coordination by an international entity to serve as a guiding coalition to stimulate collaborative research and facilitate stakeholder involvement. Contemporary developments in the field of modern biotechnology, and in particular GM, requires competencies beyond the field of biology, and the future of transgenic mosquitoes will hinge on the ability to govern the process of their introduction in societies in which perceived risks may outweigh rational and responsible involvement.

The papers presented in this issue are focused on developing and validating procedures to improve the overall quality of sterile fruit flies for use in area-wide integrated pest management (AW-IPM) programs with a sterile insect technique (SIT) component. The group was coordinated and partially funded by the Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria, under a five-year Coordinated Research Project (CRP) on “Quality Assurance in Mass-Reared and Released Fruit Flies for Use in SIT Programmes”. Participants in the CRP from 16 countries came from both basic and applied fields of expertise to ensure that appropriate and relevant procedures were developed. A variety of studies was undertaken to develop protocols to assess strain compatibility and to improve colonization procedures and strain management. Specific studies addressed issues related to insect nutrition, irradiation protocols, field dispersal and survival, field...

The ability to genetically engineer insects other than Drosophila melanogaster has further extended modern genetic techniques into important insect pest species ranging from fruit fly pests of horticulture to mosquito vectors of human disease. In only a relatively short period of time, a range of transgenes have been inserted into more than 10 insect pest species. Genetic transformation of these pest species has proven to be a very important laboratory tool in analyzing gene function and effects on phenotype however the full extension of this technology into the field is yet to be realized. Here we briefly review the development of transgenic technology in pest insect species and discuss the challenges that remain in this applied area of insect genetics and entomology.

In the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), exposure to α-copaene, a botanically derived male attractant, and ginger root oil (GRO), Zingiber officinale (Roscoe), which contains α-copaene, increased the mating success of wild males, and GRO enhanced mating competitiveness of mass-reared males from a bisexual, mass-reared strain. The present study extends this research by examining the effects of GRO exposure on the mating success of mass-reared males from a genetic sexing strain based on a temperature sensitive lethal (tsl) mutation. Such strains are currently used for nearly all sterile insect technique (SIT) programs for this insect. In addition, potential negative effects of GRO exposure on male survival and female remating propensity were investigated. Following exposure to GRO, males from the tsl mass-reared strain showed enhanced mating performance against wild-like males from two recently established colonies. Against wild-like males from a Guatemala strain, th...

The Sterile Insect Technique (SIT) is amongst the most non-disruptive pest control methods. Unlike some other biologically-based methods it is species specific, does not release exotic agents into new environments and does not even introduce new genetic material into existing populations as the released organisms are not self-replicating. However, the SIT is only effective when integrated on an areawide basis, addressing the total population of the pest, irrespective of its distribution. There has been considerable progress in the development and integrated application of the SIT against the Mediterranean fruit fly (medfly), Ceratitis capitata, as reflected by operational programs for prevention, suppression and eradication of this pest. There is however, considerable scope for improving the efficiency of medfly SIT, an indispensable requirement for increased involvement of the private sector in any future application. One way to achieve this has been the development of genetic sexing strains, making it possible to release only sterile males. Another is improving sterile male performance through a better understanding of the sexual behavior of this insect. Unlike other insects for which the SIT has been successfully applied, medfly has a complex lek-based mating system in which the females exert the mate choice selecting among aggregated and displaying wild and sterile males. With the objective of developing a better understanding of medfly mating behavior, an FAO/IAEA Coordinated Research Project was carried out from 1994 to 1999. Some of the resulting work conducted during this period with the participation of research teams from ten countries is reported in this issue.

The introduction of genetic sexing strains (GSS) into medfly, Ceratitis capitata(Wiedemann), sterile insect technique (SIT) programmes started in 1994 and it was accompanied by extensive evaluation of the strains both in field cages and in open field situations. Two male-linked translocation systems, one based on pupal colour, wp, and the other based on temperature sensitivity, tsl, have been used in medfly SIT programmes and they have quite different impacts on mass rearing strategy. In strains based on tsl, female zygotes are killed using high temperature and for wpstrains, female and male pupae are separated based on their colour. In all these systems the colony females are homozygous for the mutation requiring that the mutation is not too deleterious and the males are also semi-sterile due to the presence of a male-linked translocation. Managing strain stability during large-scale mass rearing has presented some problems that have been essentially solved by selecting particular translocations for GSS and by the introduction of a filter rearing system (FRS). The FRS operates by removing from the colony any recombinant individuals that threaten the integrity of the strain. The use of GSS opens up the possibility of using the SIT for suppression as opposed to eradication and different radiation strategies can be considered. Some of the many field trials of the strains that were carried out before the strains were introduced into operational programmes are reviewed and an overview is given of their current use.

Despite the liberal use of broad-spectrum insecticides to keep many insect pests of agricultural and veterinary importance at bay, food losses, both pre- and post-harvest, due to these insect pests contribute significantly to the high prevalence of undernourishment in the world. New, innovative pest control tactics and strategies are therefore needed that are both effective and not detrimental to the environment. As part of the arsenal of environmentally-friendly control tactics, the sterile insect technique (SIT) has proven to be a very effective tool against selected insect pests when used as part of an area-wide integrated pest management (AW-IPM) approach. Likewise, the use of natural enemies for augmentative or inundative biological control is now a major component of pest control in many parts of the world. Both control tactics are complementary and even synergistic under certain circumstances, but their combined use has so far not been applied on an operational scale. Ionising radiation can be readily employed to effectively and safely induce sexual sterility in insects. Although the sterile insect technique has often been associated with an eradication strategy, major advances in rearing efficiency, and improved handling and release methods, have made the use of sterile insects economically feasible for insect pest suppression, prevention or containment. Recently, more emphasis has been placed on the quality of the sterile insect once released in the field rather than mainly assessing quality in the rearing facility. This combined with other innovations such as the development of genetic sexing strains, better understanding the impact of radiation on radio-resistant species such as Lepidoptera and the development of the F1 sterility concept, advances in monitoring the induced sterility, etc. have significantly increased the efficiency of the sterile insect technique for several insect species. The action of sterile insects is inversely dependent on the density of the target population, and sterile insects have the intrinsic capacity to actively search for and mate with the last individuals of a pest population. These two characteristics make them ideal to deal with outbreaks of invasive insect pests. The use of sterile insects presents no threat to the environment, but aspects such as diet and waste disposal in large rearing facilities or bio-security in cases where the rearing facility is located in an area that is already free of the pest require the necessary attention. Ionising radiation can also be applied to greatly improve the efficiency of mass-rearing, handling and shipment of insect parasitoids and predators. Area-wide integrated pest management programmes that use sterile insects or natural enemies are complex and management-intensive, and require a management structure that is exclusively dedicated to the programme. Past and current examples have shown the enormous benefit-cost ratios that these programmes can generate and their importance for enhanced agriculture is increasing in significance.

Publisher Summary This chapter describes sterile insect techniques (SIT). It is a biologically based method for the control of key insect pests. Wild female insects inseminated by released, radiation-sterilized males do not reproduce, and repeated releases of the sterilized insects lead to a reduction in pest population numbers. Effective control using sterile insects is achieved when they are used systematically as part of area-wide integrated pest management (AW-IPM) programs. SIT is species-specific, nonpolluting, and resistance-free. Since the original concept was developed in the United States in the 1940s, SIT has been used successfully for screwworm flies, tsetse flies, fruit flies, and moths. Technical progress in behavioral ecology, mass rearing, strain improvement, global information, positioning and monitoring systems, and aerial release, combined with economies of scale and a growing demand for pest-free and low-pesticide agricultural products in local and international trade, have increased the use of SIT in AW-IPM programs. These programs, by decreasing insecticide use, have also facilitated the use of biological control agents against secondary insect pests.

Research on sterile mosquito technology from 1955 to the 1980s provided a substantial body of knowledge on propagation and release of sterile mosquitoes. Radiation sterilisation and chemosterilisation have been used effectively to induce dominant lethality and thereby sterilise important mosquito vectors in the laboratory. Experimental releases of chemosterilised males provided complete control of Anopheles albimanus in a small breeding population (14-15 sq km) in El Salvador. Releases of radiation sterilised males failed to control either Aedes aegypti or Anopheles quadrimaculatus in the USA. Releases of radiation-sterilised and chemosterilised male Culex quinquefasciatus in the USA and India were successful in some instances. Development of genetic sexing systems for Anopheles and improved physical separation methods for Culex have made it possible to rear and release males almost exclusively (> 99%) minimizing the release of potential vectors, the females. Factors that affected efficacy in some field programmes included reduction of competitiveness by radiation, immigration of fertilized females from outside the release zones, and inability of laboratory-bred males to perform in the wild. Despite significant progress, institutional commitments to carry the process further were generally lacking in the late 1970s and until recently. Now, with renewed interest and support for further assessment of this technology, this paper summarizes the current knowledge base, prioritizes some areas of investigation, and challenges scientists and administrators to maintain an awareness of progress, remain realistic about the interpretation of new findings, and make decisions about the sterile insect technique on the basis of informed scientific documentation. Areas recommended for priority research status include the establishment of genetic sexing mechanisms that can be transferred to other mosquito species, re-examination of radiation sterilisation, aerial release technology and mass rearing.

Since 1982 when transgenesis of Drosophila melanogaster splashed onto the scientific scene, 1,2 members of the vector biology community (e.g., refs. 3, 4) and international public health organization5 have recognized the potential utility of transgenesis to produce a modern incarnation of a historically puzzling observation: “anophelism without malaria:” The presence of anophelines but without disease. The corresponding concept among arbovirologists does not have a similarly appealing description, but the essence is the same: replacement of mosquito populations that are capable of transmitting disease with modified populations that are not. Visionary proponents argue that such a strategy is not only technically feasible, but that it leverages the power of biotechnology and a modern understanding of the means by which modified phenotypes can be spread through populations using transposable elements, cytoplasmic incompatibility, homing endonucleases, and meiotic drive. If theoretical possibilities are realized, such a vector population transformation would have minimal disruption to an ecosystem due to specific modification of only one vector/pathogen interaction and that without the use of drugs or environmentally harmful insecticides. Advocates cautiously emphasize that such applications will likely never be magic bullet solutions, and that they will be implemented only in integrated vector management programs. Nonetheless, realization of such a goal would be a remarkable demonstration of biological power for the benefit of human health.

Integrated pest management (IPM) has remained the dominant paradigm of pest control for the last 50 years. IPM has been endorsed by essentially all the multilateral environmental agreements that have transformed the global policy framework of natural resource management, agriculture, and trade. The integration of a number of different control tactics into IPM systems can be done in ways that greatly facilitate the achievement of the goals either of field-by-field pest management, or of area-wide (AW) pest management, which is the management of the total pest population within a delimited area. For several decades IPM and AW pest control have been seen as competing paradigms with different objectives and approaches. Yet, the two “schools” have gradually converged, and it is now generally acknowledged that the synthesis, AW-IPM, neither targets only eradication, nor relies only on single control tactics, and that many successful AW programmes combine a centrally managed top-down approach with a strong grassroots bottom-up approach, and that some are managed in a fully bottom-up manner. AW-IPM is increasingly accepted especially for mobile pests where management at a larger scale is more effective and preferable to the uncoordinated field-by-field approach. For some livestock pests, vectors of human diseases, and pests of crops with a high economic value and low pest tolerance, there are compelling economic incentives for participating in AW control. Nevertheless issues of free riders, public participation and financing of public goods, all play a significant role in AW-IPM implementation. These social and managerial issues have, in several cases, severely hampered the positive outcome of AW programmes; and this emphasises the need for attention not only to ecological, environmental, and economic aspects, but also to the social and management dimensions. Because globalization of trade and tourism are accompanied by the increased movement of invasive alien pest species, AW programmes against major agricultural pests are often being conducted in urban and suburban areas. Especially in such circumstances, factors likely to shift attitudes from apathy to outrage, need to be identified in the programme planning stage and mitigated. This paper reviews the evolution and implementation of the AW-IPM concept and documents its process of development from basic research, through methods development, feasibility studies, commercialization and regulation, to pilot studies and operational programmes.

Integrated pest management (IPM) has remained the dominant paradigm of pest control for the last 50 years. IPM has been endorsed by essentially all the multilateral environmental agreements that have transformed the global policy framework of natural resource management, agriculture, and trade. The integration of a number of different control tactics into IPM systems can be done in ways that greatly facilitate the achievement of the goals either of field-by-field pest management, or of area-wide (AW) pest management, which is the management of the total pest population within a delimited area. For several decades IPM and AW pest control have been seen as competing paradigms with different objectives and approaches. Yet, the two “schools” have gradually converged, and it is now generally acknowledged that the synthesis, AW-IPM, neither targets only eradication, nor relies only on single control tactics, and that many successful AW programmes combine a centrally managed top-down approach with a strong grassroots bottom-up approach, and that some are managed in a fully bottom-up manner. AW-IPM is increasingly accepted especially for mobile pests where management at a larger scale is more effective and preferable to the uncoordinated field-by-field approach. For some livestock pests, vectors of human diseases, and pests of crops with a high economic value and low pest tolerance, there are compelling economic incentives for participating in AW control. Nevertheless issues of free riders, public participation and financing of public goods, all play a significant role in AW-IPM implementation. These social and managerial issues have, in several cases, severely hampered the positive outcome of AW programmes; and this emphasises the need for attention not only to ecological, environmental, and economic aspects, but also to the social and management dimensions. Because globalization of trade and tourism are accompanied by the increased movement of invasive alien pest species, AW programmes against major agricultural pests are often being conducted in urban and suburban areas. Especially in such circumstances, factors likely to shift attitudes from apathy to outrage, need to be identified in the programme planning stage and mitigated. This paper reviews the evolution and implementation of the AW-IPM concept and documents its process of development from basic research, through methods development, feasibility studies, commercialization and regulation, to pilot studies and operational programmes.

Traditional chemically based methods for insect control have been shown to have serious limitations, and many alternative approaches have been developed and evaluated, including those based on the use of different types of mutation. The mutagenic action of ionizing radiation was well known in the field of genetics long before it was realized by entomologists that it might be used to induce dominant lethal mutations in insects, which, when released, could sterilize wild female insects. The use of radiation to induce dominant lethal mutations in the sterile insect technique (SIT) is now a major component of many large and successful programs for pest suppression and eradication. Adult insects, and their different developmental stages, differ in their sensitivity to the induction of dominant lethal mutations, and care has to be taken to identify the appropriate dose of radiation that produces the required level of sterility without impairing the overall fitness of the released insect. Sterility can also be introduced into populations through genetic mechanisms, including translocations, hybrid incompatibility, and inherited sterility in Lepidoptera. The latter phenomenon is due to the fact that this group of insects has holokinetic chromosomes. Specific types of mutations can also be used to make improvements to the SIT, especially for the development of strains for the production of only male insects for sterilization and release. These strains utilize male translocations and a variety of selectable mutations, either conditional or visible, so that at some stage of development, the males can be separated from the females. In one major insect pest, Ceratitis capitata, these strains are used routinely in large operational programs. This review summarizes these developments, including the possible future use of transgenic technology in pest control.

The extensive antigenic variation phenomena African trypanosomes display in their mammalian host have hampered efforts to develop effective vaccines against trypanosomiasis. Human disease management aims largely to treat infected hosts by chemotherapy, whereas control of animal diseases relies on reducing tsetse populations as well as on drug therapy. The control strategies for animal diseases are carried out and financed by livestock owners, who have an obvious economic incentive. Sustaining largely insecticide-based control at a local level and relying on drugs for treatment of infected hosts for a disease for which there is no evidence of acquired immunity could prove extremely costly in the long run. It is more likely that a combination of several methods in an integrated, phased and area-wide approach would be more effective in controlling these diseases and subsequently improving agricultural output. New approaches that are environmentally acceptable, efficacious and affordable are clearly desirable for control of various medically and agriculturally important insects including tsetse. Here, Serap Aksoy and colleagues discuss molecular genetic approaches to modulate tsetse vector competence.

Since the introduction of the phenothiazine drugs, reports have appeared in the literature concerning various neurological disorders resulting from their use. These reactions have included generalized clonic convulsions, cataleptoid states, parkinsonlike symptoms, and a variety of dystonic disorders. 1 The term "neck-face syndrome" was first used by Shanon 2 in discussing a group of patients treated with perphenazine (Trilafon) who developed dystonia involving the musculature of the face and neck. This paper is a report of three patients receiving different drugs of the phenothiazine group, who manifested the aforementioned syndrome. To the best of our knowledge, two of the drugs mentioned have not before been reported as causing the syndrome. Report of Cases Case 1.— A 49-year-old man was given perphenazine on Aug. 24, 1959, in a dosage of 4 mg. three times a day for symptoms of nervousness. After taking four tablets over a 36-hour period, he noted thickening

The effect of age on male Glossina fuscipes fuscipes, Newstead, and Glossina palpalis palpalis, Austin (Diptera: Glossinidae) competiveness were investigated with a view to estimate optimal age for sterile male release. Sterile insect technique involves the mass production, sterilization and sequential release of males of the target species to out compete the wild male population. Mating between released sterile males and wild females produce inviable progeny and the population is reduced over several generations to unsustainable levels. It is vital that the released male are of high quality and are sexually competitive. Age is one parameter affecting the sexual competiveness of the male tsetse fly. The optimal release age was estimated by assessing sexual competitiveness of flies of different age categories, 1, 5, 8 and 13-days after adult eclosion. A walk-in field-cage was used in order to approximate as closely as possible the actual field scenario during sterile insect release programes. It was shown that 8 and 13-day old males mated significantly more frequently, i.e. were more competitive, in the presence of equal numbers of 1 and 5-day old males. The age of male tsetse flies significantly affected competitiveness in both species studied. The ability of G. f. fuscipes to inseminate was not age dependent, and insemination occurred in all females that mated regardless of male age. In G. p. palpalis, however, 1-day old males were least able to inseminate. Mating duration was not significantly affected by age in both species. Eight to thirteen day old males of the test species are here recommended as the optimal sterile male release age. Résumé L'effet de l'âge sur la compétitivité des mâles de Glossina fuscipes fuscipes et de Glossina palpalis palpalis a été étudié en vue de déterminer l'âge optimal pour le lâcher de mâles stériles. La technique de l'insecte stérile (TIS) consiste en une production de masse, en la stérilisation et au lâchage de mâles de l'espèce cible afin qu'ils competissent avec la population de mâles sauvages. L'accouplement entre mâles stériles lâches et femelles sauvages ne produit pas de progéniture, ce qui conduit au bout de plusieurs générations à une réduction de la population à un niveau non sur vivable. Il est primordial que les mâles lâches soient de bonne qualité et sexuellement compétitifs. L'âge est l'un des paramètres affectant la compétitivité des mouches tsetse mâles. Il était donc nécessaire d'estimer l'âge optimal pour lâcher des mâles en comparant la compétitivité de différentes catégories d́âges (1, 5, 8 et 13 jours après leur émergence). La méthode dite du « field-cage » a été utilisée afin d'étudier le comportement des mâles TIS dans les conditions aussi proches que possible de la réalité. Il a été démontré que les mâles de 8 et 13 jours s'accouplent plus fréquemment que les mâles de 1 a 5 jours. Pour les deux espèces étudiées, l'âge affecte significativement la compétitivité des tsetse mâles. La capacité des mâles de G. f. fuscipes à inséminer n'est pas fonction de l'âge ; toutes les femelles accouplées sont inséminées. Chez G. p. palpalis cependant, les mâles de 1 jours sont les moins inséminées. La durée de l'accouplement n'est pas significativement affectée par l'âge dans les deux espèces. Les mâles de 8 et 13 jours des deux espèces testées sont les plus recommandés pour le lâcher des mâles stériles.

The occurrence of untoward sequelae following translumbar aortography has been stated to be minimal in the hands of a careful operator.* It is considered by some that most accidents associated with the procedure have been caused by the use of unsuitable contrast media, such as sodium iodide. 3 Despite the fact that the newer concentrated organic iodides have given rise to fewer side-effects, a possible complication of aortography which still exists is the injection of a high concentration of dye into a major branch of the aorta. It is the purpose of this paper to report a case of acute pancreatitis following such an occurrence. This has not been reported before in the literature. REPORT OF A CASE A 51-year-old white male proofreader was admitted to the Surgical A Service of Jefferson Medical College Hospital on Jan. 17, 1955. He gave a history of having enjoyed good health until four

OBSTRUCTION OF THE DISTAL ESOPHAGUS by impacted meat must be considered in the differential diagnosis of any patient presenting with the sudden onset of dysphagia. The individual is usually elderly and most often has an inadequate masticatory apparatus due to ill-fitting dentures. Although endoscopie evaluation and removal of the foreign body is frequently necessary, treatment by enzymatic digestion is of value and should be given consideration as a primary approach. Three cases have recently been encountered in which this technique proved most successful. Report of Cases Case1.—An 81-year-old female was seen on Jan. 11, 1962, complaining of tbe sudden onset of dysphagia occurring 48 hours previously, while eating meatballs. Subsequently, she noted substernal distress and rgurgitation when she attempted to eat or drink. Medical history revealed the occurrence ot frequent episodes oi diffuse substernal pain, usually caused by nervousness, which had been diagnosed as esophageal spasm by another physician.