RESUMEN
The World Health Organization (WHO) recommends periodic assessment of the therapeutic efficacy of praziquantel (PZQ) to detect reduced efficacy that may arise from drug resistance in schistosomes. In this multi-country study (2014), we assessed the therapeutic efficacy of a single oral dose of PZQ (40 mg/kg) against Schistosoma mansoni (Brazil, Cameroon, Ethiopia, Mali, Madagascar and Tanzania), S. haematobium (Cameroon, Ethiopia, Mali, Tanzania and Zanzibar) and S. japonicum (the Philippines) infections in school-aged children, across a total of 12 different trials. Each trial was performed according to the standardized methodology for evaluating PZQ efficacy as described by the WHO. Overall, therapeutic efficacy, measured as the reduction in arithmetic mean of schistosome egg counts following drug administration (egg reduction rate; ERR), was high for all three schistosome species (S. mansoni: 93.4% (95%CI: 88.8-96.8); S. haematobium: 97.7% (95%CI: 96.5-98.7) and S. japonicum: 90.0% (95%CI: 68.4-99.3). At the trial level, therapeutic efficacy was satisfactory (point estimate ERR ≥90%) for all three Schistosoma species with the exception of S. mansoni in Cameroon where the ERR was 88.5% (95%CI: 79.0-95.1). Furthermore, we observed that in some trials individual drug response could vary significantly (wide 95%CI) and that few non-responsive individuals could significantly impact ERR point estimates. In conclusion, these results do not suggest any established reduced efficacy of the standard PZQ treatment to any of the three schistosome species within these countries. Nevertheless, the substantial degree of variation in individual responses to treatment in some countries underpins the need for future monitoring. The reported ERR values serve as reference values to compare with outcomes of future PZQ efficacy studies to ensure early detection of reduced efficacies that could occur as drug pressure continues increase. Finally, this study highlights that 95%CI should be considered in WHO guidelines to classify the therapeutic efficacy of PZQ.
Asunto(s)
Antihelmínticos , Praziquantel/uso terapéutico , Esquistosomiasis mansoni/tratamiento farmacológico , Animales , Antihelmínticos/uso terapéutico , Brasil , Niño , Etiopía , Humanos , Schistosoma mansoni , TanzaníaRESUMEN
Taenia solium cysticercosis is a significant public health problem in endemic countries. The current serodiagnostic techniques are not able to differentiate between infections with viable cysts and infections with degenerated cysts. The objectives of this study were to identify specific novel biomarkers of these different disease stages in the serum of experimentally infected pigs using ProteinChip technology (Bio-Rad) and to validate these biomarkers by analyzing serum samples from naturally infected pigs. In the experimental sample set 30 discriminating biomarkers (p<0.05) were found, 13 specific for the viable phenotype, 9 specific for the degenerated phenotype and 8 specific for the infected phenotype (either viable or degenerated cysts). Only 3 of these biomarkers were also significant in the field samples; however, the peak profiles were not consistent among the two sample sets. Five biomarkers discovered in the sera from experimentally infected pigs were identified as clusterin, lecithin-cholesterol acyltransferase, vitronectin, haptoglobin and apolipoprotein A-I.
Asunto(s)
Biomarcadores/sangre , Cisticercosis/veterinaria , Análisis por Matrices de Proteínas , Enfermedades de los Porcinos/diagnóstico , Animales , Apolipoproteína A-I/sangre , Cromatografía Liquida , Clusterina/sangre , Cisticercosis/sangre , Cisticercosis/diagnóstico , Femenino , Haptoglobinas/análisis , Masculino , Perú , Fosfatidilcolina-Esterol O-Aciltransferasa/sangre , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Porcinos , Enfermedades de los Porcinos/sangre , Enfermedades de los Porcinos/parasitología , Taenia solium , Espectrometría de Masas en Tándem , Vitronectina/sangre , ZambiaRESUMEN
Taenia solium-taeniasis and cysticercosis were studied in the human and porcine populations of a rural community in the Southern Ecuadorian Andes. From the 1059 inhabitants, 800 serum samples and 958 stool samples could be collected. In addition, 646 from the estimated 1148 pigs were tongue inspected. Circulating antigen was detected by enzyme linked immunosorbent assay (Ag-ELISA) in 2.25% of the human population, whereas intestinal taeniasis was detected in 1.46% by the formalin-ether technique. Following treatment and recovery of tapeworm fragments these were all identified as T. solium. Porcine cysticercosis was diagnosed in 3.56% of the pigs by tongue inspection. In addition, enzyme linked immunoelectrotransfer blot (EITB) was performed on a subset group of 100 humans to confirm the results of the Ag-ELISA. One hundred serum samples from pigs were also analysed by EITB. It appeared that 43 and 74% of humans and pigs had antibodies against T. solium cysticerci, respectively. It is concluded that contrary to the high exposure of the human population to T. solium that is suggested by EITB, the number of active cysticercosis cases, diagnosed by Ag-ELISA, was low, which may indicate endemic stability. The further use of complementary diagnostic methods for a better understanding of the epidemiology of T. solium is suggested.
Asunto(s)
Anticuerpos Antihelmínticos/sangre , Enfermedades Endémicas , Taenia solium/aislamiento & purificación , Teniasis/diagnóstico , Adolescente , Adulto , Anciano , Animales , Niño , Cisticercosis/diagnóstico , Cisticercosis/epidemiología , Cisticercosis/veterinaria , Ecuador/epidemiología , Heces/parasitología , Humanos , Tamizaje Masivo , Persona de Mediana Edad , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , Población Rural , Estaciones del Año , Porcinos , Enfermedades de los Porcinos/diagnóstico , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/parasitología , Taenia solium/genética , Taenia solium/inmunología , Teniasis/epidemiología , Teniasis/veterinariaRESUMEN
Taenia solium-taeniasis and cysticercosis were studied in the human and porcine populations of a rural community in the Southern Ecuadorian Andes. From the 1059 inhabitants, 800 serum samples and 958 stool samples could be collected. In addition, 646 from the estimated 1148 pigs were tongue inspected. Circulating antigen was detected by enzyme linked immunosorbent assay (Ag-ELISA) in 2.25 percent of the human population, whereas intestinal taeniasis was detected in 1.46 percent by the formalin-ether technique. Following treatment and recovery of tapeworm fragments these were all identified as T. solium. Porcine cysticercosis was diagnosed in 3.56 percent of the pigs by tongue inspection. In addition, enzyme linked immunoelectrotransfer blot (EITB) was performed on a subset group of 100 humans to confirm the results of the Ag-ELISA. One hundred serum samples from pigs were also analysed by EITB. It appeared that 43 and 74 percent of humans and pigs had antibodies against T. solium cysticerci, respectively. It is concluded that contrary to the high exposure of the human population to T. solium that is suggested by EITB, the number of active cysticercosis cases, diagnosed by Ag-ELISA, was low, which may indicate endemic stability. The further use of complementary diagnostic methods for a better understanding of the epidemiology of T. solium is suggested.
Asunto(s)
Humanos , Animales , Anticuerpos Antihelmínticos/sangre , Cisticercosis/diagnóstico , Enfermedades Endémicas , Taenia solium/aislamiento & purificación , Teniasis/diagnóstico , Cisticercosis/sangre , Cisticercosis/epidemiología , Cisticercosis/veterinaria , Ensayo de Inmunoadsorción Enzimática , Ecuador/epidemiología , Heces/parasitología , Immunoblotting , Tamizaje Masivo , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , Población Rural , Estaciones del Año , Porcinos , Enfermedades de los Porcinos/diagnóstico , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/parasitología , Taenia solium/genética , Taenia solium/inmunología , Teniasis/sangre , Teniasis/etiología , Teniasis/veterinariaRESUMEN
The construction of the Diama dam on the Senegal river, the Manantali dam on the Bafing river, Mali and the ensuing ecological changes have led to a massive outbreak of Schistosoma mansoni in Northern Senegal, associated with high intensity of infections, due to intense transmission, and the creation of new foci of S. haematobium. Data on the vectorial capacity of Biomphalaria pfeifferi from Ndombo, near Richard Toll, Senegal are presented with sympatric and allopatric (Cameroon) S. mansoni. Comparisons are made on infectivity, cercarial production, chronobiology of cercarial emergence and longevity of infected snails. Recent data on the intermediate host specificity of different isolates of S. haematobium from the Lower and Middle Valley of the Senegal river basin (SRB) demonstrate the existence of at least two strains of S. haematobium. The role of Bulinus truncatus in the transmission of S. haematobium in the Lower and Middle Valleys of the SRB is reviewed. Both S. haematobium and S. mansoni are transmitted in the same foci in some areas of the SRB.
Asunto(s)
Agua Dulce/parasitología , Schistosoma haematobium/aislamiento & purificación , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis Urinaria/transmisión , Esquistosomiasis mansoni/transmisión , Animales , Biomphalaria/parasitología , Biomphalaria/fisiología , Bulinus/parasitología , Bulinus/fisiología , Brotes de Enfermedades , Vectores de Enfermedades , Humanos , Schistosoma haematobium/fisiología , Schistosoma mansoni/fisiología , Esquistosomiasis Urinaria/epidemiología , Esquistosomiasis mansoni/epidemiología , Senegal/epidemiologíaRESUMEN
The construction of the Diama dam on the Senegal river, the Manantali dam on the Bafing river, Mali and the ensuing ecological changes have led to a massive outbreak of Schistosoma mansoni in Northern Senegal, associated with high intensity of infections, due to intense transmission, and the creation of new foci of S. haematobium. Data on the vectorial capacity of Biomphalaria pfeifferi from Ndombo, near Richard Toll, Senegal are presented with sympatric and allopatric (Cameroon) S. mansoni. Comparisons are made on infectivity, cercarial production, chronobiology of cercarial emergence and longevity of infected snails. Recent data on the intermediate host specificity of different isolates of S. haematobium from the Lower and Middle Valley of the Senegal river basin (SRB) demonstrate the existence of at least two strains of S. haematobium. The role of Bulinus truncatus in the transmission of S. haematobium in the Lower and Middle Valleys of the SRB is reviewed. Both S. haematobium and S. mansoni are transmitted in the same foci in some areas of the SRB