In vitro PHYTOTHERAPY OF VECTOR SNAILS BY BINARY COMBINATIONS OF LARVICIDAL ACTIVE COMPONENTS IN EFFECTIVE CONTROL OF FASCIOLIASIS / Fitoterapia in vitro de caramujos vetores por combinações binárias de componentes ativos larvicidas como controle efetivo de fasciolíase

SUMMARY A food-borne trematode infection fascioliasis is one among common public health problems worldwide. It caused a great economic loss for the human race. Control of snail population below a certain threshold level is one of the important methods in the campaign to reduce the incidence of fascioliasis. The life cycle of the parasite can be interrupted by killing the snail or Fasciola larva redia and cercaria inside of the snail Lymnaea acuminata. In vitro toxicity of different binary combinations (1:1 ratio) of plant-derived larvicidal active components such as citral, ferulic acid, umbelliferone, azadirachtin and allicin against Fasciola redia and cercaria were tested. The mortality of larvae was observed at 2h, 4h, 6h and 8h of treatment. In in vitro condition azadirachtin + allicin (1:1 ratio) was highly toxic against redia and cercaria (8h LC50 0.006 and 0.005 mg/L). Toxicity of citral + ferulic acid was lowest against redia and cercaria larvae. .

RESUMO A infecção alimentar pelo trematóide da fasciolíase é uma dentre os mais comuns problemas de saúde pública mundiais, causando grande prejuízo econômico para a humanidade. Controle da população de caramujos abaixo de determinado nível é um dos métodos no campo mais importantes para a redução da incidência da fasciolíase. O ciclo de vida do parasita pode ser interrompido pela morte do caramujo ou da larva redia e cercária da Fasciola dentro da Lymnaea acuminata. Foi testada a toxicidade in vitro das diferentes combinações binárias (relação 1:1) entre os vários componentes larvicidas ativos da planta tais como citral, ácido ferúlico, umbeliferone, azadiractina, e alicina contra a Fasciola redia e a cercária. A mortalidade das larvas foi observada após duas, quatro, seis e oito horas de tratamento. A condição in vitro azadiractina + alicina (relação 1:1) foi altamente tóxica contra redia e cercária (8h LC50 0,006 e 0,005 mg/L). Toxicidade do citral + ácido ferúlico foi a mais baixa contra redia e larvas de cercária. .

Fasciolosis humana y animal en el Perú: impacto en la economía de las zonas endémicas / Human and animal fascioliasis in Peru: impact in the economy of endemic zones

Fasciola hepatica es el agente etiológico de la fasciolosis en el Perú. La fasciolosis es un problema de salud pública por la alta prevalencia de la infección humana, especialmente niños y un problema veterinario de importancia por las altas tasas de infección del ganado en la mayoría de regiones del País. La fasciolosis es endémica en la sierra y la costa, y esporádica en la región amazónica. La infección humana se reporta en 18 regiones y la animal en 21 de las 24 regiones del Perú. La transmisión humana ocurre en poblaciones andinas rurales dedicadas a la agricultura, pero hay un creciente número de casos en ciudades. Diferentes situaciones epidemiológicas de la infección humana se presentan: i) Regiones con casos no autóctonos, donde la infección es por consumo de vegetales contaminados traídos de zonas endémicas; ii) Regiones con poblados hipo- y mesoendémicos, transmisión local y prevalencia < 10 por ciento; y iii) Regiones con poblados hiperendémicos, transmisión local y prevalencia ≥ 10 por ciento. El parásito infecta a vacunos, ovinos, equinos, caprinos, porcinos, camélidos, cobayos y conejos. La pérdida ganadera anual por la fasciolosis es no menor de US$ 50 millones, estimada por la prevalencia de la infección y los decomisos de hígados de vacunos en mataderos. Es difícil estimar el impacto económico de la fasciolosis humana por su estatus de enfermedad desatendida, lo cierto es que la fasciolosis es endémica, y en algunos casos hiperendémica, en las regiones más pobres de nuestro país, donde la situación debe ser reconocida como una emergencia de salud pública.

Fasciola hepatica is the causative agent of fasciolosis in Peru; the disease is an important public health problem by the high prevalence of the human infection affecting mainly children and a major veterinary problem by the high rates of infected livestock. The human disease is endemic in the Sierra and the Coast but sporadic in the Amazonia, and reported in 18 Departments, while the animal infection in 21 of 24 Departments of Peru. Transmission occurs in Andean rural populations engaged in agriculture, but recently an increasing number of people became infected in the cities. The epidemiological situation in Peru includes i) Departments with non-autochtonous cases, where infection occurs by consumption of contaminated vegetables brought from endemic areas or infection is acquired by visit to endemic areas; ii) Departments with hypoendemic and mesoendemic villages, where transmission occurs by ingest of contaminated vegetables and prevalence ≤10 percent; and iii) Departments with hyper-endemic villages with human prevalence >10 percent, with an intense transmission by consumption of contaminated vegetables. The disease affects bovine, sheep, goat, swine, equine, South American camelids, rabbits and guinea pigs. The negative impact of fasciolosis in the livestock economy is not lesser than US$ 50 million per year, estimation based on the prevalence and the number of condemned livers in the abattoirs. It is difficult to estimate the economic impact of this infection in the human health due to its status of neglected disease, but fasciolosis is hyper-endemic in the poorest Andean areas of Peru where the situation has to be recognized as a public health emergency.

Zonas hiperendémicas y mesoendémicas de la infección por fasciola hepática aledañas a la ciudad de Lima: una enfermedad emergente? / Hyperendemic and mesoendemic zones of the infection by hepatic fasciola bordering to the city of Lima: an emergent disease?

Introducción: La infección causada por F. hepática es endémica en el Perú con un creciente número de áreas endémicas, el reporte de estas es esencial para conocer el impacto de la infección en la población. Objetivo: Reportar la tasa de prevalencia de fasciolosis en zonas donde previamente no se habían detectado casos humanos. Material y métodos: Se estudiaron 3 distritos alrededor de la ciudad de Lima: La Chaqui, provincia de Canta; San Lorenzo de Quinti y San Miguel de Sangallaya, provincia de Huarochirí, pertenecientes al departamento de Lima. Se incluyó a niños y adultos jóvenes (menores de 25 años). Cada muestra de heces se analizó mediante la Técnica de Sedimentación Rápida de Lumbreras. Resultados: La prevalencia global por métodos coprológicos en los tres distritos fue 8.6 por ciento (n=291); 3.9 por ciento (n=102) en La Chaqui, 26.9 por ciento (n=27) en San Miguel de Sangallaya, y 8.6 por ciento (n=163) en San Lorenzo de Quinti. Conclusión: La infección por F. hepática infection es un problema de Salud Pública en pueblos alrededor de la ciudad de Lima. Por lo tanto, las medidas de control y prevención, a parte de ser dirigidas a pobladores autóctono, deben tomar en cuenta grupos de alto riesgo como viajeros frecuentes y personas con regímenes dietéticos basados en vegetales crudos.

Introduction: The infection caused by F. hepatica is endemic in Perú with anincreasing number of endemic areas, the reporting of them is essential to know the impact of the infection in the population. OBJECTIVE: To report the prevalence rate of fascioliasis in areas where it had not been detected human cases previously. MATERIAL AND METHODS: Three districts in Lima department were studied; La Chaqui,province of Canta; San Lorenzo of Quinti and San Miguel of Sangallaya, province of Huarochirí. It included children and young adults (less than 25 years old). One stool sample by person was collected and processed by means of the Rapid Sedimentation Technique described by Lumbreras. RESULTS: Overall, the prevalence rate in the three districts was 8.6 per cent (n=291); 3.9 per cent (n=102) in La Chaqui, 26.9 per cent (n=27) in San Miguel of Sangallaya, and 8.6 per cent (n=163) inSan Lorenzo of Quinti. CONCLUSION: F. hepatica infection is a Health Public problem in populations surrounding Lima city. Therefore, control and prevention measurements, besides being addressed to authoctonus people, should also take into account high-risk groups such as frequent travelers to endemic areas and people with dietetic programs based on raw vegetables.

Molluscicidal activity of Lawsonia inermis and its binary and tertiary combinations with other plant derived molluscicides.

Molluscicidal activity of leaf, bark and seed of Lawsonia inermis against Lymnaea acuminata and Indoplanorbis exustus was studied. Highest toxicity was observed in the seed of Lawsonia inermis. Toxicity of binary (1:1) and tertiary (1:1:1) combinations of the essential oil of cedar (Cedrus deodara Roxh) and neem (Azadirachta indica A. Juss), powder from bulb of garlic (Allium sativum Linn), and oleoresin extracted from rhizome of ginger (Zingiber officinale Rosc) with Lawsonia inermis and Embelia ribes fruit powder were studied against L. acuminata and I. exustus. L. inermis seed powder in combination with Cedrus deodara oil and Azadirachta indica oil was more toxic than their individual components and other combinations.

Actividad molusquicida del Paraiso (Melia azedarach L.) (Meliaceae) sobre Lymnaea cubensis, molusco vector de Fasciolosis / Molluscicidal activity of Paraiso (Melia azedarach L.) (Meliaceae) on Lymnaea cubensis, host snail of Fasciolosis

A Fasciolosis constitui em diversas regiöes fonte importante de perdas econômicas, e quando näo se adotam medidas de controle de seus hospedeiros (moluscos), junto a condiçöes ecológicas favoráveis, pode ocorrer o aparecimento de casos isolados de Fasciolosis humana. Dentro dos métodos alternativos para o seu controle está o uso de extratos vegetais e se tem pretendido avaliar o provável emprego do suco extraíso do fruto e sementes do Paraiso (Melia azedarach L.), no controle de Lymnaea cubensis, principal vetor da Fasciolosis em Cuba. Diferentes concentraçöes do suco extraído do fruto e semente do Paraiso (Melia azedarach L.) foram testadas para determinar as doses médias letais (DL50) e máxima (DL90) usando um programa computadorizado PROBIT-LOG. Sete séries experimentais foram realizadas, usando 72 moluscos em cada uma. Para determinar a influência sobre a freqüência cardíaca foram testados três grupos de 10 moluscos, dois foram tratados com as CL50=0,88627 e CL90=1,7641, respectivamente, enquanto que o terceiro foi considerado como controle. Observou-se uma marcada influência de ambas as doses sobre a freqüência cardíaca do molusco estudado. Os resultados foram alentadores, pois demonstraram um potencial uso dessa planta no controle de moluscos näo desejados

Vaccination against schistosomiasis and fascioliasis with the new recombinant antigen Sm14: potential basis of a multi-valent anti-helminth vaccine?

Molecular cloning of components of protective antigenic preparations have suggested that related parasite fatty acid binding proteins could form the basis of the well documented protective, immune cross reactivity between the parasitic trematode worms Fasciola hepatica and Schistosoma mansoni. We have now confirmed the cross protective potential of parasite fatty acid binding proteins and suggest that it may be possible to produce a single vaccine that would be effective against at least two parasites, F. hepatica and S. mansoni of veterinary and human importance respectively.

Cultivo de Fossaria cubensis (Pfeiffer) (Pulmonata: Lymnaeidae) hospedero intermediario de Fasciola hepatica (Linnaeus) en Cuba / Culture of Fossaria cubensis (Pfeiffer)(Pulmonata:Lymnaeidae) intermediate host of Fasciola hepatica (Linnaeus) in Cuba

Se evaluo un metodo para el cultivo masivo de Fossaria cubensis (Pfeiffer) hospedero intermediario principal de la fascioliasis en Cuba. Para ello se diseno un algario a base de un cultivo de algas cianofitas de los generos Lyngbya, Leptolyngbya, Phormidium y Shimidleinema, en placas de Petri de 12 cm de diametro con sustrato fangoso y altos niveles de nitraro y carbonato y carbonato de calcio. Luego de 15 dias de incubacion con luz continua, estas placas fueron utilizadas como acuarios para la crias de los moluscos. Con esas condiciones, se acorta el tiempo generacional y se garantiza un crecimiento y reproduccion de Fossaria cubensis que permiten su produccion masiva para investigaciones sobre fascioliasis (AUF

Fasciola gigantica: a new method for cercarial shedding from experimentally infected lymnaea cailliaudi snails. Observations on encystment of the metacercaria and accidental excitation

Lymnaea cailliaudi were collected from the field and proved to be uninfected. The snails were maintained in the laboratory and exposed experimentally to miracidia of Fasciola gigantica. Cercarial shedding was performed by three methods reported before, and another new method was developed in this study. The new method was done by apex puncture of the shell of infected snail. It has the advantage of collection of large numbers of mature cercariae in clean and small volume of fluid within few minutes. Cercariae were found mobile and unencysted for up to one week when maintained immediately after shedding at 4C. When the cercariae were taken out of the refrigerator, encystment was observed to occur rapidly before tail detachment. Accidental excystation of metacercariae was observed during microscopic examination of samples from the stored cysts in the refrigerator. This proved that heat and light are important factors initiating excystation of the parasite

Fasciolasis Hepática en escolares: aspectos epidemiológicos distrito de el Tambo - Huancayo mayo - junio de 1991 / Liver fasciolasis in high school students: epidemiologic aspects district of El Tambo - Huancayo May - June 1991

Se realizó un estudio epidemiológico transversal en el distrito de El Tambo, provincia de Huancayo, departamento de Junín, durante los meses de mayo y junio de 1991 con el propósito de determinar la prevalencia de Fasciolasis hepática en escolares de secundaria y los factores epidemiológicos relacionados. Se seleccionó, aleatoriamente, una muestra de 400 escolares de dos colegios; se aplicó una encuesta para medir factores asociados como ocupación, consumo de plantas de tallo corto crudas, disposición de excretas, hábitos de higiene y crianza de animales; se recolectaron muestras de heces, las cuales fueron procesadas por el método de sedimentación rápida modificado por el Dr. Lumbreras. También se recolectaron caracoles y berros de las acequias de "Las Brisas" (Pilcomayo). La prevalencia de fasciolasis hepática es de 1.3 mas o menos 1.11 por ciento. El distrito mencionado es una zona urbana con condiciones desfavorables para la presencia de caracoles, pero colinda con distrito con condiciones epidemiológicas favorables para la distomatosis hepática. En los caracoles Lymnaea viatrix recolectados se halló un índice cercario de 3.8 por ciento en esta época fría no lluviosa. Se discute los resultados y se sugiere incidir en la población sobre aspectos educativos para prevenir esta infección