RESUMEN
In Nature, no individual can live in isolation; hence, living organisms are forced to interact with each other. This necessity has led many organisms to establish heterogeneous relations to enhance their ability to adapt to the environment, thus acquiring evolutionary advantages. These relationships are sometimes so intense, that on the long term the organisms may lose their individual identity. An example of these associations is the endosymbiotic ones, where eukaryote organisms generally harbor different prokaryote organisms. The endosymbiotic bacterium Wolbachia pipientis is a species described by Hertig and Wolbach in 1924. This microorganism can be isolated in a large variety of eukaryote organisms, with which it maintains different links. Until now, this species has only been described with 11 serogroups numbered from A to K within the Wolbachia genus. This work is intended to illustrate the relationship of Wolbachia pipientis with human pathogenic filaria and with arthropods, as well as to describe the implications of this bacterium in the treatment of filariasis. Finally, this work tries to describe recent studies that have targeted the use of artificially-created Wolbachia pipientis virulent strains that, once inoculated in infectious diseases-transmitting vectors, develop negative effects within them in order to, in this way, erradicate mosquito-transmitted infectious diseases for which no treatment is available at the moment or the prevention of its transmissibility has not been achieved.
En la naturaleza ningún individuo puede vivir de forma aislada, de tal forma que los organismos vivos se ven obligados a interactuar unos con otros. Esta necesidad ha llevado a que diferentes organismos establezcan relaciones heterogéneas para mejorar su capacidad de adaptación al medio, obteniendo así ventajas evolutivas. Estas relaciones a veces son tan intensas que a la larga los organismos pueden perder su identidad individual. Un ejemplo de estas asociaciones son las endosimbióticas, en las cuales generalmente organismos eucariotas albergan a diferentes organismos procariotas. La bacteria endosimbiótica Wolbachia pipientis es una especie descrita en 1924 por Hertig y Wolbach. Este microorganismo se puede aislar en gran variedad de organismos eucariotas, con los que mantiene diferentes vínculos. Hasta el momento solo se ha descrito esta especie con 11 serogrupos enumerados de la A a la K dentro del género Wolbachia. En este trabajo se pretende ilustrar la relación de Wolbachia pipientis con las filarias patógenas humanas y con los artrópodos, así como describir las implicaciones de esta bacteria en el tratamiento de las filariasis. Finalmente, se pretende exponer los estudios recientes que han apuntado el uso de cepas virulentas de Wolbachia pipientis creadas artificialmente que una vez inoculadas en los vectores transmisores de enfermedades desarrollan efectos negativos en estos, para de esa forma lograr la erradicación de enfermedades infecciosas transmitidas por mosquitos para las cuales de momento no existe tratamiento o no se ha logrado impedir su transmisibilidad.
Asunto(s)
Artrópodos/microbiología , Filariasis/prevención & control , Nematodos/microbiología , Simbiosis , Wolbachia , Animales , Filariasis/microbiología , Filariasis/transmisión , HumanosRESUMEN
Infection of mothers with schistosomiasis and filariasis has been shown to influence infant responses to neonatal Bacille Calmette-Guérin (BCG) immunization. The genetic makeup of infants is also considered an important determinant for the activity of BCG vaccine. The effect of natural resistance-associated macrophage protein 1 (NRAMP1) gene polymorphism on the efficacy of BCG vaccine was examined in neonates with helminth-infected mothers (63 infants) and the results were compared with neonates of uninfected mothers (187 infants). After BCG vaccination, assessment of scar presence, tuberculin test, stool analysis, and IgE level was performed. Polymorphism of the NRAMP1 gene was investigated by PCR amplification followed by RFLP analysis. We found that patients with heterozygosity of intron 4 (GC) and/or maternal infection with helminth parasites showed reduced efficacy of BCG vaccine against tuberculosis.
Asunto(s)
Vacuna BCG/administración & dosificación , Proteínas de Transporte de Catión/genética , Tuberculosis/inmunología , Animales , Vacuna BCG/genética , Femenino , Filariasis/inmunología , Filariasis/parasitología , Filariasis/prevención & control , Helmintos/inmunología , Helmintos/parasitología , Helmintos/patogenicidad , Humanos , Recién Nacido , Masculino , Polimorfismo de Longitud del Fragmento de Restricción , Schistosoma mansoni/efectos de los fármacos , Schistosoma mansoni/genética , Schistosoma mansoni/patogenicidad , Esquistosomiasis/inmunología , Esquistosomiasis/parasitología , Esquistosomiasis/prevención & control , Tuberculosis/genética , Tuberculosis/prevención & control , Wuchereria bancrofti/efectos de los fármacos , Wuchereria bancrofti/genética , Wuchereria bancrofti/patogenicidadRESUMEN
A bactéria endossimbionte Wolbachia tem sido sugerida como mecanismo de controle de insetos vetores e alvo para o tratamento das filarioses. Nesse contexto, estudos sobre a prevalência de Wolbachia em populações de vetores de campo, a análise da sua densidade em insetos sob diferentes condições fisiológicas e a investigação da diversidade genética da bactéria dentro e entre diferentes populações de vetores e em pacientes filarêmicos são relevantes. O presente estudo teve como objetivos: determinar o percentual de infecção em Culex quinquefasciatus e Aedes albopictus coletados em diferentes áreas da RMR - PE - BR; descrever a diversidade dos genes ftsZ e wsp nas linhagens de Wolbachia encontradas tanto nos vetores citados quanto nos vermes filariais coletados de pacientes microfilarêmicos da região; como também comparar a densidade da bactéria em duas populações de C. quinquefasciatus do estado de PE, uma susceptível e outra resistente a temefós. Nossos resultados mostraram que o simbionte Wolbachia está presente em 100 por cento dos vetores analisados quando diagnosticados pelo método de PCR seminested, o qual se mostrou mais eficiente que a PCR convencional. Quanto à densidade do endossimbionte, as fêmeas de C. quinquefasciatus resistentes a organofosforados de Santa Cruz do Capibaribe, Sertão - PE, apresentaram a densidade média, cerca de sete vezes maior que às fêmeas susceptíveis de Peixinhos, RMR - PE, confirmando dados encontrados na literatura. Isto sugere que mosquitos resistentes apresentam maior dificuldade para controlar a densidade do endossimbionte provavelmente pelo custo biológico associado à resistência. Em relação à diversidade genética, os dois genes estudados não mostraram nenhuma variação nas populações observadas. A análise de outros marcadores pode ajudar a esclarecer a relação entre hospedeiros e endossimbionte dando maior suporte ao uso de Wolbachia no desenvolvimento de novas estratégias de controle e tratamento de doenças transmitidas por vetores.
Asunto(s)
Filariasis/genética , Filariasis/patología , Filariasis/terapia , Control de Vectores de las Enfermedades , Wolbachia/genética , Aedes/parasitología , Culex/parasitología , Filariasis/prevención & control , Resistencia a los Insecticidas , Zonas Metropolitanas , Control Biológico de Vectores , Reacción en Cadena de la PolimerasaAsunto(s)
Humanos , Masculino , Femenino , Filariasis/diagnóstico , Filariasis/prevención & control , Filariasis/transmisiónAsunto(s)
Masculino , Femenino , Humanos , Filariasis/diagnóstico , Filariasis/prevención & control , Filariasis/transmisiónRESUMEN
This article discusses the relationship between the production of scientific knowledge on filariasis in Brazil and health policy-making and implementation related to control of the disease. The study presents a review of scientific output on filariasis from the creation of the Program to Combat Filariasis in the mid-20th century until the creation of the Unified National Health System (SUS) within the framework of decentralized control of endemic diseases in the country. The focus on empirical observations in Recife, a city where filariasis is present, highlights the relevant institutional processes and the role of various players. The hypothesis is that in the first half of the 20th century there was a lack of scientific knowledge and technological development to control the problem, but that after these advances were obtained, new requirements of a political nature came into play and acted as determinants for persistence of the endemic in the city.
Asunto(s)
Enfermedades Endémicas , Filariasis/epidemiología , Política de Salud , Animales , Investigación Biomédica , Brasil/epidemiología , Enfermedades Endémicas/prevención & control , Filariasis/prevención & control , Humanos , Formulación de Políticas , Administración en Salud Pública , Población UrbanaRESUMEN
To evaluate the effectiveness of salt fortified with diethylcarbamazine (DEC) and iodine for elimination of Bancroftian filariasis and iodine deficiency, all consenting residents of Miton, Haiti (n = 1,932) were given salt fortified with 0.25% diethylcarbamazine and 25 ppm of iodine for one year. Wuchereria bancrofti microfilaria prevalence and intensity, antigenemia, and urinary iodine were measured before and one year after salt distribution began. To measure the effect of DEC-fortified salt on adult worm motility, 15 microfilaria-positive men were examined by ultrasound of the scrotal area. Entomologic surveys were conducted to determine the proportion of W. bancrofti-infected Culex quinquefasciatus. After one year of treatment, the prevalence and intensity of microfilaremia were both reduced by more than 95%, while antigenemia levels were reduced by 60%. The motility of adult worms, as detected by ultrasound, was decreased, but not significantly, by DEC-fortified salt. The proportion of vector mosquitoes carrying infective stage larvae decreased significantly from 2.3% in the nine months before the intervention to 0.2% in the last three-month follow-up period. Iodine deficiency, which had been moderate to severe, was eliminated after one year of iodized salt consumption. The DEC-fortified salt was well accepted by the community and reduced microfilaremia and transmission to low levels in the absence of reported side effects. Based on these results, salt cofortified with DEC and iodine should be considered as a concurrent intervention for lymphatic filariasis and iodine deficiency elimination programs.
Asunto(s)
Antígenos Helmínticos/sangre , Dietilcarbamazina/administración & dosificación , Filariasis/prevención & control , Filaricidas/administración & dosificación , Yodo/administración & dosificación , Yodo/deficiencia , Cloruro de Sodio Dietético/administración & dosificación , Wuchereria bancrofti/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , Servicios de Salud Comunitaria , Culex/parasitología , Ensayo de Inmunoadsorción Enzimática , Femenino , Filariasis/epidemiología , Haití/epidemiología , Humanos , Lactante , Recién Nacido , Insectos Vectores/parasitología , Yodo/orina , Masculino , Persona de Mediana Edad , Prevalencia , Escroto/diagnóstico por imagen , Resultado del Tratamiento , UltrasonografíaRESUMEN
The efficacy of Bacillus sphaericus 2362 against Culex quinquefasciatus was tested in 1991-94 in a major Brazilian endemic zone for bancroftian filariasis. Continuous selection pressure against the mosquito population was sustained for 18 months through treatment of 2500 potential breeding sites occurring within a 5.7-km2 urban area in the Metropolitan Region of Recife. The impact of this control intervention was evaluated by comparing entomological indices with those from an untreated area. Application of the larvicide kept the Cx. quinquefasciatus population density significantly lower when compared to the untreated area, despite some operational difficulties. Adult densities remained lower for at least 5 months after spraying ceased. Pre-trial microfilaria rates from the untreated and operational area were 13.1% and 7.2%, respectively. A 60% reduction in human exposure to infective bites was recorded as a consequence of this vector population control.
Asunto(s)
Culex/parasitología , Filariasis/prevención & control , Control Biológico de Vectores/métodos , Animales , Brasil/epidemiología , Vectores de Enfermedades , Filariasis/parasitología , Filariasis/transmisión , Humanos , Control de Mosquitos/métodos , Estaciones del Año , Resultado del Tratamiento , Salud UrbanaRESUMEN
Lymphatic filariasis is caused by the nematodes Brugia malayi, Brugia timori, and Wuchereria bancrofti. The disease occurs in developing countries and is more frequent in urban areas. An estimated 4 billion people live in at-risk areas. In Brazil the endemic is caused by W. bancrofti and was first documented in 1878. It was first detected in Recife in 1952. Currently, Recife and Belém are the only cities in Brazil where the endemic is considered a public health problem. The objectives of this study are to discuss the epidemiology and control of lymphatic filariasis and review its control since it was reported by Rachou in 1952. We analyze the "campanhista" or campaign-oriented model employed by the Sucam/FNS institutional program, as well as several proposed innovative methods. We present available strategies for control of filariasis through primary health care services, decentralization to the local level (or "municipalization"), and community-based health programs.
Asunto(s)
Brugia Malayi , Filariasis Linfática/prevención & control , Filariasis/prevención & control , Wuchereria bancrofti , Animales , Brasil , Educación en Salud , Humanos , Atención Primaria de Salud , Población UrbanaRESUMEN
Culex quinquefasciatus is known to be an efficient insect host of Wuchereria bancrofti. In Brazil Cx. quinquefasciatus is widely distributed throughout the country and is often abundant in and around human habitations. In contrast, Bancroftian filariasis is limited to three foci in Brazil. Experiments were undertaken to compare the vector capacities of Cx. quinquefasciatus originating from Maceio (Alagoas), one of the endemic areas of W. bancrofti infection in Brazil, and Belo Horizonte (Minas Gerais), a non endemic area. Laboratory-reared Cx. quinquefasciatus were dissected 20 days after blood feeding on microfilaraemic patients. Survival rates and the number of infective larvae that developed did not differ in female mosquitoes of different origins. Thus both populations of Culex were susceptible to infection with W. bancrofti.
Asunto(s)
Animales , Culex/parasitología , Wuchereria bancrofti/parasitología , Filariasis/prevención & controlRESUMEN
A microfilaria survey was conducted in Trinidad in 1992, 12 years after mass treatment with spaced doses of diethylcarbamazine citrate (DEC-C) for the control of Bancroftian filariasis; 348 persons were examined using thick blood smears and a membrane filtration technique. They included 104 who had participated in the mass chemotherapy campaign in 1980. No Wuchereria bancrofti microfilariae were detected among 66% of the population examined. In 1980, 86 of 592 persons examined were found to be infected with W. bancrofti, 140 with Mansonella ozzardi and 44 with mixed infections, while in 1992, only M. ozzardi infections persisted despite treatment with DEC-C. Of the 104 persons reexamined 12 years later, 46 had M. ozzardi, of which five were new cases, but none had W. bancrofti. During both the 1980 and 1992 surveys, low microfilariae rates for M. ozzardi were observed among those 19 years of age or younger. Of the 302 persons newly examined in 1992, 29 were infected with significantly (P < 0.001) more males (79.3%) than females (20.9%) being microfilaremic. The combined results showed similar prevalence rates for M. ozzardi from 23.3% to 21.6% in 1980 and 1992. Nuclepore membrane filtration and thick blood films were very efficient in demonstrating the presence of microfilariae. The usefulness of these methods and spaced treatment using DEC-C are also discussed.
Asunto(s)
Dietilcarbamazina/uso terapéutico , Filariasis/prevención & control , Mansonella , Mansoneliasis/prevención & control , Wuchereria bancrofti , Adolescente , Adulto , Distribución por Edad , Animales , Niño , Preescolar , Femenino , Filariasis/epidemiología , Estudios de Seguimiento , Humanos , Lactante , Masculino , Mansoneliasis/epidemiología , Microfilarias/aislamiento & purificación , Persona de Mediana Edad , Parasitemia/epidemiología , Prevalencia , Distribución por Sexo , Trinidad y Tobago/epidemiologíaRESUMEN
A microfilaria survey was conducted in Trinidad in 1992, 12 years after mass treatment with spaced doses of diethylcarbamazine citrate (DEC-C) for the control of Bancroftian filariasis; 348 persons were examined using thick blood smears and a membrane filtration technique. They included 104 who had participated in the mass chemotherapy campaign in 1980. No Wuchereria bancrofti microfilariae were detected among 66 percent of the population examined. In 1980, 86 of 592 persons examined were found to be infected with W. bancrofti, 140 with Mansonella ozzardi and 44 with mixed infections, while in 1992, only M. ozzardi infections persisted despite treatment with DEC-C. Of the 104 persons reexamined 12 years later, 46 had M. ozzardi, of which five were new cases, but none had W. bancrofti. During both the 1980 and 1992 surveys, low microfilariae rates for M. ozzardi were observed among those 19 years of age or younger. Of the 302 persons newly examined in 1992, 29 were infected with significantly (P<0.001) more males (79.3 percent) than females (20.9 percent) being microfilaremic. The combined results showed similar prevalence rates for M. ozzardi from 23.3 percent to 21.6 percent in 1980 and 1992. Nuclepore membrane filtration and thick blood films were very efficient in demonstrating the presence of microfilariae. The usefulness of these methods and spaced treatment using DEC-C are also discussed (AU)
Asunto(s)
Humanos , 21003 , Masculino , Femenino , Preescolar , Niño , Adolescente , Adulto , Persona de Mediana Edad , Mansoneliasis/prevención & control , Mansonella , Filariasis/prevención & control , Wuchereria bancrofti , Dietilcarbamazina/uso terapéutico , Filariasis/epidemiología , Estudios de Seguimiento , Distribución por Edad , Distribución por SexoRESUMEN
Integrated control measures against Culex quinquefasciastus have been implemented in a pilot urban area in Recife, Brazil. About 3,000 breeding sites found within the operational area were responsible for very high mosquito densities recorded during the pretrial period. Physical control measures have been applied to cess pits before starting a series of 37 treatments of the other sites with Bacillus sphaericus strain 2362, over 27 months. In spite of the difficulties due to environmental conditions, very significant reductions in preimaginal population of C. quinquefasciatus were achieved and, as a consequence, low adult mosquito densities were maintained for a relatively long period of time. Entomological and environmental data gathered in this pilot project can contribute to design an integrated mosquito control program in Recife city.
Asunto(s)
Bacillus/fisiología , Culex/crecimiento & desarrollo , Filariasis/prevención & control , Control de Mosquitos/métodos , Animales , Brasil , Filariasis/transmisión , Densidad de PoblaciónAsunto(s)
Bacteriemia/transmisión , Transfusión de Componentes Sanguíneos/efectos adversos , Sangre/microbiología , Sangre/parasitología , Parasitemia/transmisión , Babesiosis/prevención & control , Babesiosis/transmisión , Bacteriemia/prevención & control , Transfusión de Componentes Sanguíneos/normas , Donantes de Sangre , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/prevención & control , Enfermedad de Chagas/transmisión , Filariasis/epidemiología , Filariasis/prevención & control , Filariasis/transmisión , Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/prevención & control , Infecciones por Bacterias Gramnegativas/transmisión , Humanos , Enfermedad de Lyme/epidemiología , Enfermedad de Lyme/prevención & control , Enfermedad de Lyme/transmisión , Malaria/epidemiología , Malaria/prevención & control , Malaria/transmisión , Parasitemia/prevención & control , Prevalencia , Sífilis/epidemiología , Sífilis/prevención & control , Sífilis/transmisión , Toxoplasmosis/epidemiología , Toxoplasmosis/prevención & control , Toxoplasmosis/transmisiónRESUMEN
Se presenta el primer caso de Microfilariasis patogena probable Mansonella Ozzardi, diagnosticado por estudio Histopalogico, en un nino de 12 anos de edad, procedente de la ciudad de Santa Cruz, con un cuadro clinico atipico y desenlace fatal