RESUMO
Controlled Human Infection Models (CHIS) involve administering human pathogens to healthy participants in controlled medical settings, which can elicit complex bioethical issues. Understanding how the community perceives such studies can significantly increase the participant's sense of cooperation and increases the researcher's and the participant's transparency. The current study describes the development of an educational intervention to achieve these ends as it aims to (1) analyze perceptions of the Controlled Human Infection Studies (CHIS), and (2) evaluate the participants' comprehension of the CHIS. METHODS: This is a qualitative action research that includes the development of an educational intervention with residents of a rural area in Minas Gerais, Brazil, where there is continuous natural transmission of the human pathogen Necator americanus ("hookworm"). In this area, it is intended to carry out a proposed phase 3 vaccine clinical trial in the future to test the efficacy of hookworm vaccines using controlled human infection. Two data collection strategies were used: an educational intervention and a focus group. RESULTS: The participants' perceptions showed distinct perspectives on CHIS. On one side, they recognized that the investigation is essential for the community, but on the other side, they thought that there would be resistance to its conduct by fear of infection. The idea that the study would generate a benefit for the greater good, contributing to the prevention of hookworm infection, was clearly stated. The participants perceived that the study offered concrete risks that could be reduced by constant monitoring by the researchers. They also mentioned the importance of access to information and the positive influence those who express interest in participating in the study can exert in the community. In relation to comprehension the participants memorized the information, mobilized it to explain everyday situations and created strategies to disseminate the study and engage the community in its development. By repeating and making sense of the information, the participant not only assimilates the knowledge transmitted, but also creates new knowledge. CONCLUSION: We concluded that an educational process of discussion and dialogue around participants' perceptions about the CHIS, promotes understanding and allows ways to disseminate information about the research to be collectively created.
Assuntos
Necator americanus , Necatoríase , Humanos , Brasil , Animais , Necator americanus/imunologia , Feminino , Necatoríase/prevenção & controle , Necatoríase/transmissão , Necatoríase/imunologia , Masculino , Adulto , Infecções por Uncinaria/prevenção & controle , Infecções por Uncinaria/transmissão , Vacinas/imunologia , Pessoa de Meia-Idade , Participação da Comunidade/métodos , Adulto Jovem , Grupos FocaisRESUMO
The subdiscipline of historical epidemiology holds the promise of creating a more robust and more nuanced foundation for global public health decision-making by deepening the empirical record from which we draw lessons about past interventions. This essay draws upon historical epidemiological research on three global public health campaigns to illustrate this promise: the Rockefeller Foundation's efforts to control hookworm disease (1909-c.1930), the World Health Organization's pilot projects for malaria eradication in tropical Africa (1950s-1960s), and the international efforts to shut down the transmission of Ebola virus disease during outbreaks in tropical Africa (1974-2019).
Assuntos
Epidemiologia/história , Saúde Global/história , Promoção da Saúde/história , Doença pelo Vírus Ebola/história , Infecções por Uncinaria/história , Malária/história , África , Controle de Doenças Transmissíveis/história , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/transmissão , História do Século XX , Infecções por Uncinaria/prevenção & controle , Humanos , Malária/prevenção & controle , Prática de Saúde Pública/história , Organização Mundial da Saúde/históriaRESUMO
Abstract The subdiscipline of historical epidemiology holds the promise of creating a more robust and more nuanced foundation for global public health decision-making by deepening the empirical record from which we draw lessons about past interventions. This essay draws upon historical epidemiological research on three global public health campaigns to illustrate this promise: the Rockefeller Foundation's efforts to control hookworm disease (1909-c.1930), the World Health Organization's pilot projects for malaria eradication in tropical Africa (1950s-1960s), and the international efforts to shut down the transmission of Ebola virus disease during outbreaks in tropical Africa (1974-2019).
Resumo A subdisciplina epidemiologia histórica se propõe a criar um alicerce robusto e refinado para o processo de tomada de decisões em saúde pública global, aprofundando registros empíricos que nos ensinam sobre intervenções passadas. Este artigo se baseia na pesquisa epidemiológica histórica de três campanhas globais de saúde pública para ilustrar essa proposta: os esforços da Fundação Rockefeller para controle da ancilostomose (1909-c.1930), os projetos-piloto da Organização Mundial da Saúde para erradicação da malária na África tropical (décadas de 1950-1960), e os esforços internacionais de interrupção da transmissão do vírus Ebola durante surtos na África tropical (1974-2019).
Assuntos
Humanos , História do Século XX , Saúde Global/história , Epidemiologia/história , Doença pelo Vírus Ebola/história , Promoção da Saúde/história , Infecções por Uncinaria/história , Malária/história , Organização Mundial da Saúde/história , Prática de Saúde Pública/história , Controle de Doenças Transmissíveis/história , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/transmissão , África , Infecções por Uncinaria/prevenção & controle , Malária/prevenção & controleRESUMO
As part of on-going efforts to control hookworm infection, the "human hookworm vaccine initiative" has recognised blood feeding as a feasible therapeutic target for inducing immunity against hookworm infection. To this end, molecular approaches have been used to identify candidate targets, such as Necator americanus (Na) haemoglobinase aspartic protease-1 (APR-1), with immunogenicity profiled in canine and hamster models. We sought to accelerate the immune analysis of these identified therapeutic targets by developing an appropriate mouse model. Here we demonstrate that Nippostrongylus brasiliensis (Nb), a phylogenetically distant strongylid nematode of rodents, begins blood feeding early in its development and that immunisation with Na-APR-1 can block its growth and completion of its life cycle. Furthermore, we identify a new haem detoxification pathway in Nb required for blood feeding that can be blocked by drugs of the quinolone family, reducing both infection burden and the associated anaemia in rodents. Collectively, our findings show that haem metabolism has potential as a checkpoint for interrupting hookworm development in early stages of the hookworm life cycle and that the Nippostrongylus brasiliensis rodent model is relevant for identifying novel therapeutic targets against human hookworm.
Assuntos
Anticorpos Anti-Helmínticos/farmacologia , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Eritrócitos/efeitos dos fármacos , Infecções por Uncinaria/prevenção & controle , Necator americanus/enzimologia , Nippostrongylus/crescimento & desenvolvimento , Infecções por Strongylida/prevenção & controle , Ancylostomatoidea/efeitos dos fármacos , Ancylostomatoidea/crescimento & desenvolvimento , Animais , Antígenos de Helmintos/imunologia , Ácido Aspártico Endopeptidases/imunologia , Eritrócitos/parasitologia , Feminino , Infecções por Uncinaria/parasitologia , Estágios do Ciclo de Vida , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nippostrongylus/efeitos dos fármacos , Infecções por Strongylida/parasitologiaRESUMO
Necator americanus Glutathione-S-Transferase-1 (Na-GST-1) plays a role in the digestion of host hemoglobin by adult N. americanus hookworms. Vaccination of laboratory animals with recombinant Na-GST-1 is associated with significant protection from challenge infection. Recombinant Na-GST-1 was expressed in Pichia pastoris and adsorbed to aluminum hydroxide adjuvant (Alhydrogel) according to current Good Manufacturing Practice. Two Phase 1 trials were conducted in 142 healthy adult volunteers in the United States and Brazil, first in hookworm-naïve individuals and then in residents of a N. americanus endemic area in Brazil. Volunteers received one of three doses of recombinant Na-GST-1 (10, 30, or 100 µg) adjuvanted with Alhydrogel, adjuvanted with Alhydrogel and co-administered with an aqueous formulation of Glucopyranosyl Lipid A (GLA-AF), or the hepatitis B vaccine. Vaccinations were administered via intramuscular injection on days 0, 56, and 112. Na-GST-1/Alhydrogel was well tolerated in both hookworm-naïve and hookworm-exposed adults, with the most common adverse events being mild to moderate injection site pain and tenderness, and mild headache and nausea; no vaccine-related severe or serious adverse events were observed. Antigen-specific IgG antibodies were induced in a dose-dependent fashion, with increasing levels observed after each vaccination in both trials. The addition of GLA-AF to Na-GST-1/Alhydrogel did not result in significant increases in specific IgG responses. In both the US and Brazil studies, the predominant IgG subclass induced against Na-GST-1 was IgG1, with lesser amounts of IgG3. Vaccination of both hookworm-naïve and hookworm-exposed adults with recombinant Na-GST-1 was safe, well tolerated, and resulted in significant antigen-specific IgG responses. Based on these results, this vaccine will be advanced into clinical trials in children and eventual efficacy studies. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01261130 for the Brazil trial and NCT01385189 for the US trial).
Assuntos
Ancylostomatoidea/imunologia , Antígenos de Helmintos/imunologia , Glutationa Transferase/imunologia , Infecções por Uncinaria/prevenção & controle , Vacinas Sintéticas/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adolescente , Adulto , Hidróxido de Alumínio/administração & dosagem , Animais , Anticorpos Anti-Helmínticos/sangue , Brasil , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Glucosídeos/administração & dosagem , Voluntários Saudáveis , Vacinas contra Hepatite B/administração & dosagem , Infecções por Uncinaria/imunologia , Humanos , Imunoglobulina G/sangue , Injeções Intramusculares , Lipídeo A/administração & dosagem , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Estados Unidos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Adulto JovemRESUMO
Informed consent is one of the principal ethical requirements of conducting clinical research, regardless of the study setting. Breaches in the quality of the informed consent process are frequently described in reference to clinical trials conducted in developing countries, due to low levels of formal education, a lack of familiarity with biomedical research, and limited access to health services in these countries. However, few studies have directly compared the quality of the informed consent process in developed and developing countries using the same tool and in similar clinical trials. This study was conducted to compare the quality of the informed consent process of a series of clinical trials of an investigational hookworm vaccine that were performed in Brazil and the United States. A standardized questionnaire was used to assess the ethical quality of the informed consent process in a series of Phase 1 clinical trials of the Na-GST-1/Alhydrogel hookworm vaccine that were conducted in healthy adults in Brazil and the United States. In Brazil, the trial was conducted at two sites, one in the hookworm non-endemic urban area of Belo Horizonte, Minas, and one in the rural, resource-limited town of Americaninhas, both in the state of Minas Gerais; the American trial was conducted in Washington, DC. A 32-question survey was administered after the informed consent document was signed at each of the three trial sites; it assessed participants' understanding of information about the study presented in the document as well as the voluntariness of their decision to participate. 105 participants completed the questionnaire: 63 in Americaninhas, 18 in Belo Horizonte, and 24 in Washington, DC. Overall knowledge about the trial was suboptimal: the mean number of correct answers to questions about study objectives, methods, duration, rights, and potential risks and benefits, was 45.6% in Americaninhas, 65.2% in Belo Horizonte, and 59.1% in Washington, DC. Although there was no difference in the rate of correct answers between participants in Belo Horizonte and Washington, DC, there was a significant gap between participants at these two locations compared to Americaninhas (p = 0.0002 and p = 0.0001, respectively), which had a lower percentage of correct answers. Attitudes towards participating in the clinical trial also differed by site: while approximately 40% had doubts about participating in Washington, DC and Belo Horizonte, only 1.5% had concerns in Americaninhas. Finally, in Belo Horizonte and Washington, high percentages cited a desire to help others as motivation for participating, whereas in Americaninhas, the most common reason for participating was personal interest (p = 0.001). Understanding of information about a Phase 1 clinical trial of an experimental hookworm vaccine following informed consent was suboptimal, regardless of study site. Although overall there were no differences in knowledge between Brazil and the US, a lower level of understanding about the trial was seen in participants at the rural, resource-limited Brazilian site. These findings demonstrate the need for educational interventions directed at potential clinical trial participants, both in developing and developed countries, in order to improve understanding of the informed consent document.
Assuntos
Ancylostomatoidea/imunologia , Infecções por Uncinaria/prevenção & controle , Consentimento Livre e Esclarecido/normas , Adolescente , Adulto , Ancylostomatoidea/fisiologia , Animais , Brasil , Estudos Transversais , Países em Desenvolvimento/estatística & dados numéricos , Estudos de Avaliação como Assunto , Feminino , Infecções por Uncinaria/parasitologia , Infecções por Uncinaria/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Estados Unidos , Vacinas/administração & dosagem , Vacinas/imunologia , Adulto JovemRESUMO
BACKGROUND: Although mass drug administration (MDA) has helped reduce morbidity attributed to soil-transmitted helminth infections in children, its limitations for hookworm infection have motivated the development of a human hookworm vaccine to both improve morbidity control and ultimately help block hookworm transmission leading to elimination. However, the potential economic and epidemiologic impact of a preventive vaccine has not been fully evaluated. METHODS: We developed a dynamic compartment model coupled to a clinical and economics outcomes model representing both the human and hookworm populations in a high transmission region of Brazil. Experiments simulated different implementation scenarios of MDA and vaccination under varying circumstances. RESULTS: Considering only intervention costs, both annual MDA and vaccination were highly cost-effective (ICERs ≤ $790/DALY averted) compared to no intervention, with vaccination resulting in lower incremental cost-effectiveness ratios (ICERs ≤ $444/DALY averted). From the societal perspective, vaccination was economically dominant (i.e., less costly and more effective) versus annual MDA in all tested scenarios, except when vaccination was less efficacious (20% efficacy, 5 year duration) and MDA coverage was 75%. Increasing the vaccine's duration of protection and efficacy, and including a booster injection in adulthood all increased the benefits of vaccination (i.e., resulted in lower hookworm prevalence, averted more disability-adjusted life years, and saved more costs). Assuming its target product profile, a pediatric hookworm vaccine drastically decreased hookworm prevalence in children to 14.6% after 20 years, compared to 57.2% with no intervention and 54.1% with MDA. The addition of a booster in adulthood further reduced the overall prevalence from 68.0% to 36.0% and nearly eliminated hookworm infection in children. CONCLUSION: Using a human hookworm vaccine would be cost-effective and in many cases economically dominant, providing both health benefits and cost-savings. It could become a key technology in effecting control and elimination efforts for hookworm globally.
Assuntos
Infecções por Uncinaria/prevenção & controle , Vacinação em Massa/economia , Modelos Econômicos , Vacinas/uso terapêutico , Adolescente , Anti-Helmínticos/uso terapêutico , Brasil , Criança , Pré-Escolar , Análise Custo-Benefício , Infecções por Uncinaria/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Vacinas/economiaRESUMO
Few data are available on the epidemiology of soil-transmitted helminths (STHs) in indigenous populations of the Peruvian Amazon. While albendazole is being increasingly used in deworming campaigns, few data exist on the impact of mass drug administration in isolated populations. We studied the prevalence of STHs, anemia, and malnutrition in a Matsigenka ethnic group from the Peruvian Amazon. Participants had received two doses of albendazole on consecutive days, 3 months before and again 2 weeks before data collection. Overall, 290 subjects were included. Most were female (53.7%) and 63.9% were ≤19 years old. Half of the participants had helminth infections. Trichiuris (30.2%), hookworm (19.1%), Ascaris (17.7%), and Strongyloides (5.6%) were the most common helminths. Other helminth ova included Capillaria hepatica and Fasciola-like eggs. Subjects of 5-19 years (51.8 %) and 20-35 years (68.6 %) old had helminths more often than those under 5 years (38%) and older than 35 years (41.5%) (P â=â 0.02). Anemia was detected in 41% of children and this was more common in children under 5 years that in those of 5-19 years [odd ratio (OR) = 5.68; 95% CI: 2.71-11.88]. Overall, 72.1% of children were malnourished. Stunting was common in children (70.7%), but wasting was not (2.9%). Despite repeated albendazole administration, this population continued to have a high prevalence of STHs, anemia, and malnutrition. In addition, we detected unusual organisms and organisms that do not respond to albendazole. Further studies are needed to assess the rationale and efficacy of mass chemotherapy for STHs in the Amazon.
Assuntos
Albendazol/administração & dosagem , Anti-Helmínticos/administração & dosagem , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/prevenção & controle , Solo/parasitologia , Adolescente , Adulto , Animais , Ascaríase/epidemiologia , Ascaríase/prevenção & controle , Criança , Pré-Escolar , Estudos Transversais , Esquema de Medicação , Fezes/parasitologia , Feminino , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/prevenção & controle , Humanos , Masculino , Infecções por Nematoides/transmissão , Contagem de Ovos de Parasitas , Peru/epidemiologia , Prevalência , Saúde Pública , Estrongiloidíase/epidemiologia , Estrongiloidíase/prevenção & controle , Tricuríase/epidemiologia , Tricuríase/prevenção & controleRESUMO
In 1915 the Rockefeller Foundation took its hookworm eradication campaign to Suriname, but was soon disappointed because of opposition from its main target group: the Javanese. Moreover, authorities and planters objected to the construction of latrines because of the costs and their belief that the Javanese were "unhygienic". In describing the labor migration from Java to Suriname, I show that this "lack of hygiene" was closely related to the system's organization. I argue that uncleanliness was the consequence of harmful socio-economic and ecological conditions. Secondly I suggest that even though the Foundation did not manage to cleanse Suriname of hookworm, its educational efforts, its emphasis on prevention, and its training of local health workers probably had more impact than Rockefeller officials thought.
Assuntos
Infecções por Uncinaria/história , Higiene/história , Saneamento/história , Fundações/história , História do Século XX , Infecções por Uncinaria/prevenção & controle , Humanos , Indonésia/etnologia , Cooperação Internacional , Suriname , Migrantes , Estados UnidosRESUMO
This study quantifies the rate and intensity of re-infection with human hookworm and Schistosoma mansoni infection 12 months following successful treatment, and investigates the influence of socio-economic, geographical and environmental factors. A longitudinal study of 642 individuals aged over 5 years was conducted in Minas Gerais State, Brazil from June 2004 to March 2006. Risk factors were assessed using interval censored regression for the rate and negative binomial regression for intensity. The crude rate and intensity of hookworm re-infection was 0·21 per year (95% confidence interval (CI) 0·15-0·29) and 70·9 epg (95% CI 47·2-106·6). For S. mansoni the rate was 0·06 per year (95% CI 0·03-0·10) and intensity 6·51 epg (95% CI 3·82-11·11). Rate and intensity of re-infection with hookworm were highest among males and positively associated with previous infection status, absence of a toilet and house structure. Rate and intensity of S. mansoni re-infection were associated with previous infection status as well as geographical, environmental and socio-economic factors. The implications of findings for the design of anti-helminth vaccine trials are discussed.
Assuntos
Ancylostomatoidea/fisiologia , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/prevenção & controle , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/prevenção & controle , Adolescente , Adulto , Assistência ao Convalescente , Idoso , Animais , Brasil , Criança , Pré-Escolar , Estudos Transversais , Características da Família , Fezes/parasitologia , Feminino , Infecções por Uncinaria/tratamento farmacológico , Infecções por Uncinaria/economia , Infecções por Uncinaria/parasitologia , Infecções por Uncinaria/transmissão , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Prevalência , Recidiva , Análise de Regressão , Características de Residência , Fatores de Risco , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/economia , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/transmissãoRESUMO
Like other countries around the globe where conditions existed for the parasites causing hookworm disease to thrive, this disease was a serious problem to settlers in countries of the Commonwealth Caribbean, i.e. those countries that were formerly part of the British Empire. Early in the 20th century, the Rockefeller Foundation (RF) assisted the southern United States in controlling this disease. Soon other countries requested assistance and the Rockefeller Foundation responded by creating their International Health Commission to target the problem. Guyana (then British Guiana) was the first country where work was started. Through a system of chemotherapy, sanitation with the provision of latrines and health education the RF assisted the Commonwealth Caribbean countries during the period 1914-1925 in controlling the disease. Most countries continued the programmes started by the Rockefeller Foundation and this paper provides evidence through a series of surveys to show that hookworm disease is no longer a public health problem.
Assuntos
Fundações/história , Infecções por Uncinaria , Agências Internacionais/história , Cooperação Internacional/história , Saúde Pública , Ancylostomatoidea , Animais , Região do Caribe/epidemiologia , Guiana/epidemiologia , História do Século XX , Infecções por Uncinaria/história , Infecções por Uncinaria/prevenção & controle , Humanos , Saúde Pública/história , Saúde Pública/métodos , Estados Unidos/epidemiologiaRESUMO
Hookworm infection is a significant problem worldwide. As development of hookworm vaccine proceeds, it is essential for vaccine developers and manufacturers, policy makers, and other public health officials to understand the potential costs and benefits of such a vaccine. We developed a decision analytic model to evaluate the cost-effectiveness of introducing a hookworm vaccine into two populations in Brazil: school-age children and non-pregnant women of reproductive age. Results suggest that a vaccine would provide not only cost savings, but potential health benefits to both populations. In fact, the most cost-effective intervention strategy may be to combine vaccine with current drug treatment strategies.
Assuntos
Ancylostomatoidea/imunologia , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/prevenção & controle , Vacinas/economia , Vacinas/imunologia , Adolescente , Adulto , Animais , Brasil/epidemiologia , Criança , Análise Custo-Benefício , Feminino , Infecções por Uncinaria/economia , HumanosRESUMO
BACKGROUND: Obtaining informed consent for clinical trials is especially challenging when working in rural, resource-limited areas, where there are often high levels of illiteracy and lack of experience with clinical research. Such an area, a remote field site in the northeastern part of the state of Minas Gerais, Brazil, is currently being prepared for clinical trials of experimental hookworm vaccines. This study was conducted to assess whether special educational tools can be developed to increase the knowledge and comprehension of potential clinical trial participants and thereby enable them to make truly informed decisions to participate in such research. METHODOLOGY/PRINCIPAL FINDINGS: An informational video was produced to explain the work of the research team and the first planned hookworm vaccine trial, using a pedagogical method based on analogies. Seventy-two adults living in a rural community of Minas Gerais were administered a structured questionnaire that assessed their knowledge of hookworm, of research and of the planned hookworm vaccine trial, as well as their attitudes and perceptions about the researchers and participation in future vaccine trials. The questionnaire was administered before being shown the educational video and two months after and the results compared. After viewing the video, significant improvements in knowledge related to hookworm infection and its health impact were observed: using a composite score combining related questions for which correct answers were assigned a value of 1 and incorrect answers a value of 0, participants had a mean score of 0.76 post-video compared to 0.68 pre-video (p = 0.0001). Similar improvements were seen in understanding the purpose of vaccination and the possible adverse effects of an experimental vaccine. Although 100% of participants expressed a positive opinion of the researchers even before viewing the film and over 90% said that they would participate in a hookworm vaccine trial, an increase in the number who expressed fear of being vaccinated with a novel vaccine was seen after viewing the video (51.4% post-video versus 29.2% pre-video). Increases were also seen in the proportion who thought that participation in a vaccine trial would be inconvenient or disrupt their daily activities. CONCLUSIONS/SIGNIFICANCE: Even in rural, resource-limited populations, educational tools can be specially designed that significantly improve understanding and therefore the likelihood of obtaining truly informed consent for participation in clinical research. The observed changes in the knowledge and perceptions of the research participants about hookworm infection and the experimental hookworm vaccine demonstrate that the video intervention was successful in increasing understanding and that the subjects acquired knowledge pertinent to the planned research.
Assuntos
Educação em Saúde/métodos , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Vacinas/imunologia , Adolescente , Adulto , Animais , Brasil/epidemiologia , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto JovemRESUMO
To what extent do tropical diseases contribute to the poverty characteristic of tropical countries? Estimates of the impact of health on income are difficult to obtain because health is a normal good-countries with higher income will buy more of it-and third factors such as remoteness and bad government might impede both productivity and public health. In the Abuja Declaration of 2005, African heads of states claim that malaria has depressed income growth in Subsaharan Africa since the 1960s, so much so that GDP in the region today is 40% lower because of malaria. Estimates of this magnitude have been mocked at cocktail parties and clambakes. But how ridiculous is this number?
Assuntos
Efeitos Psicossociais da Doença , Infecções por Uncinaria/economia , Malária/economia , África , Brasil , Criança , Epidemias/história , História do Século XIX , História do Século XX , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/prevenção & controle , Humanos , Renda , Malária/epidemiologia , Malária/prevenção & controle , Controle de Mosquitos , Sudeste dos Estados Unidos , Clima TropicalRESUMO
The article presents views from above and below of the Rockefeller Foundation's International Health Commission's (IHC's) hookworm control program in Nicaragua from 1914 to 1928. It looks at the meaning, impact, and unique configuration of the Nicaraguan mission, while taking into account the larger global institutional project of this important international health actor. Although the IHC program in Nicaragua complemented some of the social policy goals of the US intervention in Nicaragua, which was a de facto protectorate during this period, the institution cannot be considered a direct expression or agent of US foreign policy. Ultimately the shape and limits of the IHC mission to Nicaragua were determined by the institutional project of the international public health agency itself, and by local considerations ranging from the characteristics of the staff to the response of rural communities to the anti-hookworm campaigns.
Assuntos
Fundações/história , Infecções por Uncinaria/história , Missões Médicas/história , Saúde Pública/história , História do Século XX , Infecções por Uncinaria/prevenção & controle , Humanos , Nicarágua , Política , Estados UnidosRESUMO
Hookworm infection and schistosomiasis are two of the world's most important human parasitic infections, affecting hundreds of millions of people in developing countries. Measured together in disability-adjusted life years, hookworm infection and schistosomiasis rank closely behind malaria as the most prevalent human parasitic diseases. A major approach for the control of these two helminth infections relies on periodic, mass chemotherapy with anthelminthics. However, high rates of post-treatment reinfection, the declining efficacy with repeated treatment, rebound morbidity (in the case of schistosomiasis) and the potential for the emergence of anthelminthic drug resistance threaten the sustainability of mass drug administration as the only form of control. Hence, there is a strong rationale for developing a vaccine that simultaneously targets both hookworms and schistosomes because of similarities in the pathobiology of both parasites, the ability of both helminths to cause anemia and their coendemicity in sub-Saharan Africa, Brazil and East Asia. A multivalent anthelminthic vaccine for hookworm infection and schistosomiasis would represent an important new tool for combating disease and poverty.
Assuntos
Ancylostomatoidea/imunologia , Infecções por Uncinaria/prevenção & controle , Schistosoma/imunologia , Esquistossomose/prevenção & controle , Vacinas/imunologia , África Subsaariana/epidemiologia , Animais , Ásia/epidemiologia , Brasil/epidemiologia , Infecções por Uncinaria/epidemiologia , Humanos , Esquistossomose/epidemiologiaRESUMO
The earliest programs of the Rockefeller Foundation's International Health Commission - IHC were pilot projects for the treatment of hookworm disease in the British colonies of British Guiana and Trinidad. These pioneering ventures into international health have often been portrayed as governed by rigid biomedical principles. In contrast to this view, the article emphasizes the degree to which the exigencies of a public health project that sought to make biomedicine intelligible within the medical systems of subject populations combined with the knowledge of local IHC staff members of Indo-Caribbean descent to generate some fascinating experiments in ethno-medical translation. One term in particular "The Demon that Turned into Worms" is focused on to show how these efforts at medical translation may have legitimized and promoted medical pluralism.
Assuntos
Saúde Global , Infecções por Uncinaria , Agências Internacionais , Cooperação Internacional , Saúde Pública , Animais , Antropologia Cultural/história , Antropologia Cultural/métodos , Etnicidade/etnologia , Etnicidade/história , Guiana/epidemiologia , Guiana/etnologia , História do Século XX , Infecções por Uncinaria/história , Infecções por Uncinaria/prevenção & controle , Humanos , Agências Internacionais/história , Cooperação Internacional/história , Medicina Tradicional/história , Necator americanus/parasitologia , Saúde Pública/história , Saúde Pública/métodos , Trinidad e Tobago/epidemiologia , Trinidad e Tobago/etnologiaRESUMO
OBJECTIVE: To assess the effect on birthweight of antenatal mebendazole plus iron vs. placebo plus iron in a highly hookworm-endemic area. METHODS: Double-blind, randomized controlled trial set in rural and peri-urban communities in the Peruvian Amazon region. A total of 1042 second trimester pregnant women between the ages of 18 and 44 years were recruited from April to November 2003, and followed to July 2004. Women were randomly assigned to receive either mebendazole (500 mg single dose) plus iron supplements (60 mg elemental iron daily) or placebo plus iron supplements. The primary outcome was mean infant birthweight and secondary measures included proportion of low birthweight babies and maternal anaemia. RESULTS: The prevalence of hookworm infection was 47.5%. There were no differences between intervention groups in mean birthweight (3104 g vs. 3090 g, P = 0.629), proportion of low birthweight (<2500 g; 8.1%vs. 8.7%, P = 0.755) or maternal anaemia in the third trimester [33.0% (158/479) vs. 32.3% (152/471), P = 0.815]. However, the proportion of very low birthweight (<1500 g) was significantly lower in the mebendazole group [0% (0/479) vs. 1.5% (7/471), P = 0.007]. CONCLUSIONS: This trial provides additional evidence for the use of anthelmintics, over and above iron supplementation, within antenatal care programmes in hookworm-endemic areas. Benefits of de-worming may be higher in countries not having an antenatal iron supplementation programme or where intensity of hookworm infections is higher.
Assuntos
Antinematódeos/uso terapêutico , Infecções por Uncinaria/prevenção & controle , Recém-Nascido de Baixo Peso , Mebendazol/uso terapêutico , Complicações Infecciosas na Gravidez/prevenção & controle , Adulto , Anemia/prevenção & controle , Método Duplo-Cego , Doenças Endêmicas , Feminino , Infecções por Uncinaria/sangue , Infecções por Uncinaria/epidemiologia , Humanos , Recém-Nascido , Malária/epidemiologia , Peru/epidemiologia , Gravidez , Complicações Hematológicas na Gravidez/sangue , Complicações Hematológicas na Gravidez/prevenção & controle , Complicações Infecciosas na Gravidez/sangue , PrevalênciaRESUMO
This paper summarises the progress towards vaccine development against the major blood-feeding nematodes of man and livestock, the hookworms and Haemonchus contortus, respectively. The impact of the diseases and the drivers for vaccine development are summarized as well as the anticipated impact of the host immune response on vaccine design. The performance requirements are discussed and progress towards these objectives using defined larval and adult antigens, many of these being shared between species. Specific examples include the Ancylostoma secreted proteins and homologues in Haemonchus as well as proteases used for digestion of the blood meal. This discussion shows that many of the major vaccine candidates are shared between these blood-feeding species, not only those from the blood-feeding stages but also those expressed by infective L3s in the early stages of infection. Challenges for the future include: exploiting the expanding genome information for antigen discovery, use of different recombinant protein expression systems, formulation with new adjuvants, and novel methods of field testing vaccine efficacy.