Health, science and development: the emergence of American cutaneous leishmaniasis as a medical and public health challenge in Amazonas state, Brazil. / Saúde, ciência e desenvolvimento: a emergência da leishmaniose tegumentar americana como desafio médico-sanitário no Amazonas.

The history of the emergence of American cutaneous leishmaniasis in the Brazilian state of Amazonas since the 1970s is analyzed as an object of knowledge and a medical and public health challenge. An overview of the period is provided, including the public health measures and scientific studies undertaken in the context of the execution of large-scale regional developments pursued in the name of national integration by the federal government. The methodology uses documental analysis of laws, the scientific literature, research reports, epidemiological bulletins, and newspapers. The results show that American cutaneous leishmaniasis emerged as a major health problem in Amazonas in close association with the political, economic, and socioenvironmental changes seen in the period.

O artigo faz análise histórica da emergência da leishmaniose tegumentar americana como objeto do conhecimento e desafio médico-sanitário no Amazonas desde a década de 1970. Fornece visão geral dessa época, as medidas sanitárias e os estudos científicos realizados no contexto de implantação dos principais projetos de desenvolvimento regionais executados em nome da política de integração nacional do governo federal. Utiliza como metodologia a análise documental de leis, produção científica, relatórios de pesquisa, boletins epidemiológicos e jornais. Os resultados da pesquisa mostram que a doença surgiu no Amazonas associando o grande problema de saúde com mudanças político-econômicas e alterações socioambientais.

Saúde, ciência e desenvolvimento: a emergência da leishmaniose tegumentar americana como desafio médico-sanitário no Amazonas / Health, science and development: the emergence of American cutaneous leishmaniasis as a medical and public health challenge in Amazonas state, Brazil

Resumo O artigo faz análise histórica da emergência da leishmaniose tegumentar americana como objeto do conhecimento e desafio médico-sanitário no Amazonas desde a década de 1970. Fornece visão geral dessa época, as medidas sanitárias e os estudos científicos realizados no contexto de implantação dos principais projetos de desenvolvimento regionais executados em nome da política de integração nacional do governo federal. Utiliza como metodologia a análise documental de leis, produção científica, relatórios de pesquisa, boletins epidemiológicos e jornais. Os resultados da pesquisa mostram que a doença surgiu no Amazonas associando o grande problema de saúde com mudanças político-econômicas e alterações socioambientais.

Abstract The history of the emergence of American cutaneous leishmaniasis in the Brazilian state of Amazonas since the 1970s is analyzed as an object of knowledge and a medical and public health challenge. An overview of the period is provided, including the public health measures and scientific studies undertaken in the context of the execution of large-scale regional developments pursued in the name of national integration by the federal government. The methodology uses documental analysis of laws, the scientific literature, research reports, epidemiological bulletins, and newspapers. The results show that American cutaneous leishmaniasis emerged as a major health problem in Amazonas in close association with the political, economic, and socioenvironmental changes seen in the period.

The importance of vector control for the control and elimination of vector-borne diseases.

Vector-borne diseases (VBDs) such as malaria, dengue, and leishmaniasis exert a huge burden of morbidity and mortality worldwide, particularly affecting the poorest of the poor. The principal method by which these diseases are controlled is through vector control, which has a long and distinguished history. Vector control, to a greater extent than drugs or vaccines, has been responsible for shrinking the map of many VBDs. Here, we describe the history of vector control programmes worldwide from the late 1800s to date. Pre 1940, vector control relied on a thorough understanding of vector ecology and epidemiology, and implementation of environmental management tailored to the ecology and behaviour of local vector species. This complex understanding was replaced by a simplified dependency on a handful of insecticide-based tools, particularly for malaria control, without an adequate understanding of entomology and epidemiology and without proper monitoring and evaluation. With the rising threat from insecticide-resistant vectors, global environmental change, and the need to incorporate more vector control interventions to eliminate these diseases, we advocate for continued investment in evidence-based vector control. There is a need to return to vector control approaches based on a thorough knowledge of the determinants of pathogen transmission, which utilise a range of insecticide and non-insecticide-based approaches in a locally tailored manner for more effective and sustainable vector control.

History of the International Organization for Biological Control Global Working Group on Mass Rearing and Quality Assurance.

The International Organization for Biological Control Global Working Group on Mass Rearing and Quality Assurance (MRQA) was established in 1980 as the Working Group on Quality Control (WGQC) to assure success of insect mass rearing for pest management that was being developed in the 1950s and 1960s. Due mostly to the efforts of WGQC, quality control became institutionalized in several insect mass rearing facilities during the 1980s. After addressing autocidal control programs, the WGQC concentrated on entomophagous insects, especially testing the quality of commercial biological control products. Universal Implementation of Quality Control for Mass-Reared Arthropods was finally achieved in the 1990s, having encompassed all aspects from insect production to field application and evaluation. This increased scope prompted a name change from WGQC to Arthropod Mass Rearing and Quality Control (AMRQC). Subsequently, the scope of the Working Group was expanded again and it was renamed MRQA to include a range of applications for mass-reared beneficial invertebrates. The geographic range of MRQA recently was extended beyond North and South America and Europe to include India. This expansion continued as insects for food and feed, networking and instruction, and legal and ethical issues were added to the most recent workshop held in Mexico. Thus, the MRQA continues to evolve as additional invertebrate organisms are mass produced for both established and novel applications.

An Unlikely Beginning: A Fortunate Life.

Elizabeth A. Bernays grew up in Australia and studied at the University of Queensland before traveling in Europe and teaching high school in London. She later obtained a PhD in entomology at London University. Then, as a British government scientist, she worked in England and in developing countries on a variety of projects concerned with feeding by herbivorous insects and their physiology and behavior. In 1983, she was appointed professor at the University of California, Berkeley, where her research expanded to a variety of topics, all related to the physiology, behavior, and ecology of feeding in insects. She was awarded a DSc from the University of London, and at about the same time became head of the Department of Entomology and regents' professor at the University of Arizona. In Arizona, most of her research involved multiple approaches to the understanding of diet breadth in a variety of phytophagous insect species.

Development of Baits for Population Management of Subterranean Termites.

The objective of bait application envisioned by early researchers was to eliminate the source of infestation, the colony, but because of the lack of adequate evaluation tools, results of field trials with mirex baits in the 1960s were mostly inconclusive. On-the-ground monitoring stations and mark-recapture protocol developed in the 1970s marked the turning point in the field studies of termite baits. Results of field studies with metabolic inhibitors and chitin synthesis inhibitors (CSIs) in the 1990s indicated that a bait toxicant has to be slow-acting and nonrepellent, and its lethal time has to be dose independent. A recent discovery that termites return to the central nest to molt and CSI-poisoned termites die near the royal pair further explains the success of CSI baits in eliminating colonies. Owing to the availability of durable baits that require less-frequent site inspection, more termite control professionals have adopted baiting systems in recent years.

Past, Present, and Future of Integrated Control of Apple Pests: The New Zealand Experience.

This review describes the New Zealand apple industry's progression from 1960s integrated pest control research to today's comprehensive integrated pest management system. With the exception of integrated mite control implemented during the 1980s, pest control on apple crops was dominated by intensive organophosphate insecticide regimes to control tortricid leafrollers. Multiple pest resistances to these insecticides by the 1990s, and increasing consumer demand for lower pesticide residues on fruit, led to the implementation of integrated fruit production. This substantially eliminated organophosphate insecticide use by 2001, replacing it with pest monitoring systems, threshold-based selective insecticides, and biological control. More recently, new demands for ultralow-residue fruit have increased the adoption of mating disruption and use of biological insecticides. Widespread adoption of selective pest management has substantially reduced the status of previously important pests, including leafrollers, mealybugs, leafhoppers, and mites for improved phytosanitary performance, and contributed to major reductions in total insecticide use.

Evolution of Chagas disease screening programs and control programs: historical perspective.

Chagas disease remains an important health problem in Latin America, affecting approximately 8 million to 10 million individuals. This disease originated from an ancient enzootic cycle, and human infection has been detected in 4,000- to 9,000-year-old mummies and has expanded with European colonization, reaching its peak prevalence in the 20th century. Discovered in 1909, the disease remained obscure and uncontrolled until the 1950s, when the generalization of serology, the characterization of chronic cardiomyopathy, and effective insecticides began. By the 1960s, national control programs were launched and incidence began to decrease as a result. During this time, scientific improvements became increasingly available to address disease management. Presently, challenges in managing Chagas disease include maintaining sustainable epidemiological surveillance, the spread of the disease to nonendemic countries, the apparent spread of oral transmission, and new symptoms and manifestations. This review discusses the possibilities and challenges in facing Chagas disease in the coming decades.

Insect control in socialist China and the corporate United States: the act of comparison, the tendency to forget, and the construction of difference in 1970s U.S.-Chinese scientific exchange.

In 1975, a delegation of U.S. entomologists traveled to socialist China to observe Chinese insect control science. Their overwhelmingly positive reports highlighted in relief the pernicious effects of pesticide corporations on U.S. agriculture; some entomologists hoped this would goad the United States to catch up to China in environmentally sensible insect control practices. Of course, insect control in socialist China carried its own political baggage, some of which-for example, mass mobilization and self-reliance--the state made highly visible to visitors, and some of which--for example, harsh treatment of scientists--it sought to obscure. For both the U.S. and the Chinese participants, the act of comparison itself was of primary significance in the exchange, allowing them to construct socialist Chinese science as refreshingly different from U.S. science. At the same time, however, this construction of difference meant forgetting the much longer transnational history in which U.S. and Chinese entomology had been intertwined.

Cultural diabrotica containment strategy in Switzerland: until now a convincing success story.

Ever since 2000 Switzerland belongs to the 22 European countries where the quarantine pest Diabrotica virgifera virgifera LeConte, Western corn rootworm (WCR), has been detected. It is reported to be the most important maizepest worldwide with an economic damage reaching 1.5 billion US$. In Switzerland it is constantly present in the southern part of the Alps while only few beetles are sporadically found in the northern part. Observations from 2000 up to 2012 support the hypothesis that the populations in the southern part of the Alps are generated by yearly migrations from principal foci situated in neighbouring Italian areas of Lombardy. Neither the tight correlation between travel distance and time of first arrival at various points from South to North, nor the steady decline of population along the route can be explained otherwise. Control measures enacted by Swiss authorities were principally based on a tightly enforced crop rotation scheme without chemical inputs as usually practiced in parts of the European Union. The effectiveness of crop rotation has been tested in a 5 year field trial comparing a continuous maize cropping system with a croprotation system and a maximum of one year of maizewithin a two year period (1:1). Population density was measured using synthetic pheromone baited traps and observations of root damage. Results showed that no economically relevant population built up during this period in the crop rotation treatment, whereas in the statistical evaluation of continuous maizecropping root damages could be detected after 4 years. One to one (1:1) year crop rotations are a common practice since 2001 in Southern Switzerland and are well accepted by farmers. Consequently, not a gram of pesticide has been employed against WCR in Switzerland up to now. The low level population density also helped to avoid the introduction of WCR populations into Cantons north of the Alps and thus prevented further spreading towards the state territories of northern neighbours.

[The beginning of Chagas disease control (homage to Dr. Emmanuel Dias, the pioneer of Chagas disease control, in the year of his birth centenary)]. / Os primórdios do controle da doença de Chagas (em homenagem a Emmanuel Dias, pioneiro do controle, no centenário de seu nascimento).

Very soon Carlos Chagas took into account the need of trypanosomiasis control, considering its great social impact and geographical dispersion The vector was considered the more vulnerable target and housing improvement the basic strategy to face the disease. In parallel, it was required a more clinical visibility for the disease, as an argument for its control. The first concrete tentative occurred in 1918 when Souza Araújo dedicating his efforts in Paraná, trying housing improvement. He was followed by Ezequiel Dias et al, in 1921, employing chemical compounds against the vector, The chemical fight will be retaken by Emmanuel Dias in 1944, assaying several old compounds, fire thrower and cyanidric gas. In 1946, DDT showed to be ineffective, but one year later Dias & Pellegrino described the insecticide gammexane, highly effective against domestic triatomines. Working with Mario Pinotti, expanded trials occurred in Minas Gerais (Triangle Region), justifying the expansion of the campaign to other endemic regions, with the rationale of continuous work in contiguous areas. In 1957 Pedreira de Freitas proposed the selective spraying, which was the model for the future strategy of program evaluation, by SUVEN and SUCAN organizations. In 1975 the national program is reorganized, launching two national surveys (entomology and serology). In 1979 the new pyrethroid compounds are tried and im 1983 the national program is expanded. Transfusion transmitted Chagas Disease was studied since the 1950 by the Nussenzweig group in S. Paulo, showing to be vulnerable to chemoprophylaxis and blood donor pre transfusional serologic screening. Nevertheless, these preventive measures only were implemented in the 1980 decade, following the emergence of HIV/AIDS pandemic. Practically, since the pioneer essays, the control of Chagas Disease transmission showed to be efficient against vector and blood bank mechanisms, depending on continuity, educative support and political will.

[Institutional insertion of Chagas' disease control]. / A inserção institucional do controle da doença de Chagas.

After the starting of the Center for studies and prophylaxis of Chagas disease in 1943, with the help of Oswaldo Cruz Foundation, in the city of Bambuí, state of Minas Gerais, technological and methodological basis for the extensive control of the disease were conceived. A main step to achieve success was the introduction of a new insecticide (gammexane, P 530) and the demonstration of its efficacy in the vector control. A consequence of these improvements was the official inauguration of the first prophylactic campaign for Chagas disease in Brazil, held in Uberaba in May, 1950. Even with the knowledge of how to control the vectorial transmission, financial resources were not available by this time, at a necessary degree to make it both regularly and in all the affected area. The institutional allocation of these activities is useful to understand the low priority given to them at that time. Several national services were created in 1941, for diseases as malaria, pest, smallpox, among others, but Chagas was included in a group of diseases with lower importance, inside a Division of Sanitary Organization. In 1956, the National Department of Rural endemies (DNERu) allocate all the major endemic diseases in a single institution, however this was not translated in an implementation program for the control of Chagas disease. After profound changes at the Ministry of Health, in 1970, the Superintendência de Campanhas de Saúde Pública (SUCAM) was in charge of all rural endemies including Chagas disease, which now could compete with other diseases transmitted by vectors, formerly priorities, included in the National Division. With this new status, more funds were available, as well as redistribution of personnel and expenses from the malaria program to the vectorial control of Chagas disease. In 1991 the Health National foundation was created to substitute SUCAM in the control of endemic diseases and it included all the units of the Ministry of Health related to epidemiology and disease control. By this time a new tendency for decentralization of these programs was clear. In the case of diseases transmitted by vectors, this was a major difference from the campaign model so far employed. At the same time, the Initiative for the South Cone countries for the control of Chagas disease started, sharing techniques among the countries of this region, as well as establishing similar objectives and trends, what possible helped to maintain Chagas disease as a priority among all the public health issues. From 2003 on, all activities for control of the disease at a national level are under responsibility of the Secretary of Health Surveillance of the Ministry of Health.

[The control of vectorial transmission]. / O controle da transmissão vetorial.

Between 1950 and 1951, the first Prophylactic campaign against Chagas Diseases was carried on in Brazil by the so existing Serviço Nacional de Malária. The actions involving chemical vector control comprehended 74 municipalities along the Rio Grande Valley, between the States of São Paulo and Minas Gerais. Ever since, until 1975, the activities were performed according the availability of resources, being executed with more or less regularity and coverage. At that time, Chagas disease did no represent priority, in comparison with other endemic diseases prevalent in the Country. Even so, taking into account the accumulated data along those 25 years, the volume of work realized cannot be considered despicable. Nevertheless, it was few consistent, in terms of its impact on disease transmission. In 1975, with an additional injection of resources surpassed from the malaria program, plus the methodological systematization of the activities, and with the results of two extensive national inquiries (entomologic and serologic), the activities for vector control could be performed regularly, following two basic principles: interventions in always contiguous areas, progressively enlarged, and sustainability (continuity) of the activities, until being attained determined requirements and purpose previously established. Such actions and strategies lead into the exhaustion of the populations of the principal vector species, Triatoma infestans, no autochthonous and exclusively domiciliary, as well as the control of the domiciliary colonization of autochthonous species important to disease transmission. Vector transmission today is being considered residual, by means of some few native and peridomestic species, such as Triatoma brasiliensis and Triatoma pseudomaculata. There is, also, the risk of progressive domiciliation of some species before considered sylvatic, such as Panstrongylus lutzi and Triatoma rubrovaria. Finally, there is the possibility of the occurrence of cases of human infection directly related to the enzootic cycle of the parasite. By all these reasons, it is still indispensable the maintenance of a strict epidemiological surveillance against Chagas Disease in Brazil.

A history of chagas disease transmission, control, and re-emergence in peri-rural La Joya, Peru.

BACKGROUND: The history of Chagas disease control in Peru and many other nations is marked by scattered and poorly documented vector control campaigns. The complexities of human migration and sporadic control campaigns complicate evaluation of the burden of Chagas disease and dynamics of Trypanosoma cruzi transmission. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a cross-sectional serological and entomological study to evaluate temporal and spatial patterns of T. cruzi transmission in a peri-rural region of La Joya, Peru. We use a multivariate catalytic model and Bayesian methods to estimate incidence of infection over time and thereby elucidate the complex history of transmission in the area. Of 1,333 study participants, 101 (7.6%; 95% CI: 6.2-9.0%) were confirmed T. cruzi seropositive. Spatial clustering of parasitic infection was found in vector insects, but not in human cases. Expanded catalytic models suggest that transmission was interrupted in the study area in 1996 (95% credible interval: 1991-2000), with a resultant decline in the average annual incidence of infection from 0.9% (95% credible interval: 0.6-1.3%) to 0.1% (95% credible interval: 0.005-0.3%). Through a search of archival newspaper reports, we uncovered documentation of a 1995 vector control campaign, and thereby independently validated the model estimates. CONCLUSIONS/SIGNIFICANCE: High levels of T. cruzi transmission had been ongoing in peri-rural La Joya prior to interruption of parasite transmission through a little-documented vector control campaign in 1995. Despite the efficacy of the 1995 control campaign, T. cruzi was rapidly reemerging in vector populations in La Joya, emphasizing the need for continuing surveillance and control at the rural-urban interface.

Os primórdios do controle da doença de Chagas (em homenagem a Emmanuel Dias, pioneiro do controle, no centenário de seu nascimento) / The beginning of Chagas Disease control (homage to Dr. Emmanuel Dias, the pioneer of Chagas Disease control, in the year of his birth centenary)

Carlos Chagas se apercebe precocemente da necessidade do controle da doença, frente ao seu impacto social e grande dispersão. O vetor é o elo mais vulnerável e a melhoria da habitação a estratégia mais exeqüível. Em paralelo, há que dar-se visibilidade à doença, para justificar o controle. Como primeiras tentativas concretas, Souza Araújo pleiteará reformas de vivendas, no Paraná (1918), e Ezequiel Dias e cols ensaiarão inúmeros compostos químicos contra os triatomíneos (1921). A luta anti triatomínica será retomada por Emmanuel Dias a partir de 1944, em Bambuí, re testando compostos antigos, lança chamas e gás cianídrico. Em 1946 decepciona-se com o DDT, mas, em 1947, com Pellegrino ensaia com êxito o gammexane (BHC PM). Aliando-se a Pinotti, logo partem para ensaios de campo no Triângulo Mineiro, justificando expansão para outras áreas. A estratégia básica é a luta química continuada, em áreas endêmicas contínuas. Em 1959, Pedreira de Freitas descreve o expurgo seletivo, formatando a etapa de avaliação, da SUCEN e da futura SUCAM. Em 1975, o programa nacional é normatizado e armam-se inquéritos nacionais (triatomíneos e sorológico). Em 1979 ensaiam-se novos piretróides e em1983 o programa nacional é expandido. Estudada desde 1950 pelo grupo de Nussenzweig, em São Paulo, a transmissão transfusional mostra-se vulnerável ao controle por quimioprofilaxia e seleção sorológica de doadores, mas só se implementa, em definitivo, nos anos 1980, com a emergência da pandemia de HIV/AIDS. Praticamente desde os trabalhos pioneiros, o controle da tripanossomíase evidenciou-se eficiente, desde que continuado e sustentado por ações educativas e por decisão política.

Very soon Carlos Chagas took into account the need of trypanosomiasis control, considering its great social impact and geographical dispersion The vector was considered the more vulnerable target and housing improvement the basic strategy to face the disease. In parallel, it was required a more clinical visibility for the disease, as an argument for its control. The first concrete tentative ocorred in 1918 when Souza Araújo dedicating his efforts in Paraná, trying housing improvement. He was followed by Ezequiel Dias et al, in 1921, employing chemical compounds against the vector, The chemical fight will be retaken by Emmanuel Dias in 1944, assaying several old compounds, fire thrower and cyanidric gas. In 1946, DDT showed to be ineffective, but one year later Dias & Pellegrino described the insecticide gammexane, higly effective against domestic triatomines. Working with Mario Pinotti, expanded trials occurred in Minas Gerais (Triangle Region), justifying the expansion of the campaing to other endemic regions, with the rationale of continuous work in contiguous areas. In 1957 Pedreira de Freitas proposed the selective spraying, which was the model for the future strategy of program evaluation, by SUVEN and SUCAN organizations. In 1975 the national program is reorganized, launching two national surveys (entomology and serology). In 1979 the new pyrethroid compounds are tried and im 1983 the national program is expanded. Transfusion transmitted Chagas Disease was studied since the 1950 by the Nussenzweig group in S. Paulo, showing to be vulnerable to chemoprophylaxis and blood donor pre transfusional serologic screening. Nevertheless, these preventive measures only were implemented in the 1980 decade, following the emergence of HIV/AIDS pandemic. Practically, since the pioneer essays, the control of Chagas Disease transmission showed to be efficient against vector and blood bank mechanisms, depending on continuity, educative support and political will.

A inserção institucional do controle da doença de Chagas / Institutional Insertion of Chagas' disease control

Em 1943, a partir da criação do "Centro de Estudos e Profilaxia da Moléstia de Chagas" da Fundação Oswaldo Cruz de Bambuí em Minas Gerais, são concebidas as bases tecnológicas e metodológicas para o controle extensivo da enfermidade. Para isso foi decisivo o advento de um novo inseticida (o gammexane, P 530) e a demonstração de sua eficácia no controle dos vetores da doença de Chagas. Como resultado prático desses acontecimentos em "maio de 1950 foi oficialmente inaugurada, em Uberaba, a primeira campanha de profilaxia da doença de Chagas, no Brasil". Mesmo que se dispusesse desde então de meios para fazer o controle da transmissão vetorial da endemia chagásica, não se dispunha dos recursos financeiros exigidos para fazê-lo de forma abrangente e regular. O baixo nível de prioridade conferida a essa atividade se expressava em sua inserção institucional. Em 1941, foram criados os Serviços Nacionais, de malária, peste, varíola, entre outros, enquanto a doença de Chagas fazia parte da Divisão de Organização Sanitária (DOS), que reunia enfermidades consideradas de menor importância. Em 1956 o Departamento Nacional de Endemias Rurais (DNERu) incorporou todas as chamadas grandes endemias em uma única instituição, mas na prática isso não significou a implementação das ações de controle da doença de Chagas. Com a reestruturação do Ministério da Saúde em 1970, a Superintendência de Campanhas de Saúde Pública (SUCAM) abarcou todas as endemias rurais, e a doença de Chagas passou a ter o status de Divisão Nacional, na mesma posição hierárquica daquelas outras doenças transmitidas por vetores antes consideradas prioritárias. Essa condição determinou a possibilidade de uma repartição de recursos mais equilibrada, o que efetivamente ocorreu, com a realocação de pessoal e insumos do programa de malária para o controle vetorial da doença de Chagas. Em 1991, a Fundação Nacional de Saúde sucedeu a SUCAM no controle das doenças endêmicas, congregando ademais todas as unidades e serviços do Ministério da Saúde relacionados à epidemiologia e ao controle de doenças. Já então a tendência era a descentralização operativa destes programas, o que no caso das doenças transmitidas por vetores representava uma drástica mudança no modelo campanhista até então vigente. À época, coincidentemente, foi formada a Iniciativa dos Países do Cone Sul para o controle da doença de Chagas, com o trabalho tecnicamente compartido entre os países da região, com metas e objetivos comuns, o que de algum modo contribuiu para que fosse preservada a doença de Chagas como prioridade entre os problemas de saúde. Desde 2003 as atividades de controle da doença no nível central nacional estão sob responsabilidade da Secretaria de Vigilância em Saúde do Ministério da Saúde.

After the starting of the Center for studies and prophylaxis of Chagas disease in 1943, with the help of Oswaldo Cruz Foundation, in the city of Bambuí, state of Minas Gerais, technological and methodological basis for the extensive control of the disease were conceived. A main step to achieve success was the introduction of a new insecticide (gammexane, P 530) and the demonstration of its efficacy in the vector control. A consequence of these improvements was the official inauguration of the first prophylactic campaign for Chagas disease in Brazil, held in Uberaba in May, 1950. Even with the knowledge of how to control the vectorial transmission, financial resources were not available by this time, at a necessary degree to make it both regularly and in all the affected area. The institutional allocation of these activities is useful to understand the low priority given to them at that time. Several national services were created in 1941, for diseases as malaria, pest, smallpox, among others, but Chagas was included in a group of diseases with lower importance, inside a Division of Sanitary Organization. In 1956, the National Department of Rural endemies (DNERu) allocate all the major endemic diseases in a single institution, however this was not translated in an implementation program for the control of Chagas disease. After profound changes at the Ministry of Health, in 1970, the Superintendência de Campanhas de Saúde Pública (SUCAM) was in charge of all rural endemies including Chagas disease, which now could compete with other diseases transmitted by vectors, formerly priorities, included in the National Division. With this new status, more funds were available, as well as redistribution of personnel and expenses from the malaria program to the vectorial control of Chagas disease. In 1991 the Health National foundation was created to substitute SUCAM in the control of endemic diseases and it included all the units of the Ministry of Health related to epidemiology and disease control. By this time a new tendency for decentralization of these programs was clear. In the case of diseases transmitted by vectors, this was a major difference from the campaign model so far employed. At the same time, the Initiative for the South Cone countries for the control of Chagas disease started, sharing techniques among the countries of this region, as well as establishing similar objectives and trends, what possible helped to maintain Chagas disease as a priority among all the public health issues. From 2003 on, all activities for control of the disease at a national level are under responsibility of the Secretary of Health Surveillance of the Ministry of Health.

O controle da transmissão vetorial / The control of vectorial transmission

Entre 1950 e 1951, foi realizada a primeira Campanha de Profilaxia da Doença de Chagas, no Brasil, conduzida pelo então Serviço Nacional de Malária. Abrangeu, com ações de controle vetorial químico, 74 municípios ao longo do Vale do Rio Grande, na divisa dos Estados de Minas Gerais e São Paulo. Desde então até o ano de 1975 as atividades de controle foram exercidas de forma mais ou menos regular e com maior ou menor alcance, o que dependeu de um aporte descontínuo de recursos. A doença de Chagas não representava prioridade, relativamente a outras enfermidades endêmicas prevalentes no país. Ainda assim, a julgar pelos dados acumulados ao longo daqueles 25 anos, o volume de trabalho não foi desprezível, mas pouco conseqüente em termos de seu impacto sobre a transmissão. Em 1975, com um aporte adicional de recursos, excedentes do programa de controle da malária; com a sistematização metodológica das operações; e, com base em dois extensos inquéritos epidemiológicos realizados no país, entomológico e sorológico, as ações de controle vetorial passaram a ser exercidas de forma regular, seguindo dois princípios básicos: intervenções em áreas sempre contíguas e progressivamente crescentes e sustentabilidade das atividades, até que cumpridos determinados requisitos e metas, previamente estabelecidos. Essas ações levaram ao esgotamento das populações da principal espécie de vetor, Triatoma infestans, alóctone e exclusivamente domiciliar, e ao controle da colonização intradomiciliar de espécies autóctones com importância na transmissão. A transmissão é hoje residual por algumas dessas espécies nativas, notadamente por Triatoma brasiliensis e Triatoma pseudomaculata; há o risco de domiciliação de espécies, antes consideradas de hábitos silvestres, como é o caso de Panstrongylus lutzi e Triatoma rubrovaria; além da possibilidade de que ocorram casos de infecção humana, diretamente relacionados ao ciclo enzoótico de transmissão. Por tudo isso, é ainda indispensável que se mantenha estrita vigilância entomológica.

Between 1950 and 1951, the first Prophylactic campaign against Chagas Diseases was carried on in Brazil by the so existing Serviço Nacional de Malária. The actions involving chemical vector control comprehended 74 municipalities along the Rio Grande Valley, between the States of São Paulo and Minas Gerais. Ever since, until 1975, the activities were performed according the availability of resources, being executed with more or less regularity and coverage. At that time, Chagas disease did no represent priority, in comparison with other endemic diseases prevalent in the Country. Even so, taking into account the accumulated data along those 25 years, the volume of work realized cannot be considered despicable. Nevertheless, it was few consistent, in terms of its impact on disease transmission. In 1975, with an additional injection of resources surpassed from the malaria program, plus the methodological systematization of the activities, and with the results of two extensive national inquiries (entomologic and serologic), the activities for vector control could be performed regularly, following two basic principles: interventions in always contiguous areas, progressively enlarged, and sustainability (continuity) of the activities, until being attained determined requirements and purpose previously established. Such actions and strategies lead into the exhaustion of the populations of the principal vector species, Triatoma infestans, no autochthonous and exclusively domiciliary, as well as the control of the domiciliary colonization of autochthonous species important to disease transmission. Vector transmission today is being considered residual, by means of some few native and peridomestic species, such as Triatoma brasiliensis and Triatoma pseudomaculata. There is, also, the risk of progressive domiciliation of some species before considered sylvatic, such as Panstrongylus lutzi and Triatoma rubrovaria. Finally, there is the possibility of the occurrence of cases of human infection directly related to the enzootic cycle of the parasite. By all these reasons, it is still indispensable the maintenance of a strict epidemiological surveillance against Chagas Disease in Brazil.

Michael Elliott's billion dollar crystals and other discoveries in insecticide chemistry.

The crowning achievement for Michael Elliott came in 1973 when his most outstanding candidate insecticide from 25 years of research crystallized from hexane solution. The stereochemically pure crystalline compound was the most potent synthetic insecticide ever made until that time, and it was highly selective for insects compared with mammals. It was given the name deltamethrin. Sequential stereospecific crystallization to isolate the most potent epimer and base-catalyzed racemization of the remaining less active isomer could be used to produce deltamethrin efficiently on a large scale; it became the billion dollar crystals. Elliott's discoveries at Rothamsted in England with Norman Janes and David Pulman of resmethrin, permethrin, cypermethrin and ultimately deltamethrin provided crop protection and malaria control for millions of people. Michael also laid the background for lipophilic amide, dithiane and other insecticides and nerve probes that are not involved in pyrethroid cross-resistance. Some aspects of these investigations were best conducted at Berkeley, where Michael studied pyrethrins in 1969, synthetic pyrethroids in 1974 and alternative insecticides in 1986-1988. This review considers Michael's seminal discoveries in insecticide chemistry, with emphasis on his Berkeley years.