RESUMO
Combined coprological (by an ether-formol method) and serological (by solid-phase enzyme immunoassay--EIA) screening of the population to detect opisthorchiasis was performed in the settlements situated in the Ob, Dnieper and Northern Dvina basins. Disease rate in the hyperendemic area on the Ob exceeded 80%, by the results of coprological population screening, while annual infestation rate established on the basis of specific antibodies determination in the blood was 70%. Infestation and disease rates in mesoendemic area, at the Ob tributary and in the Dnieper basin were practically equal and accounted for 30-40%. Infestation rates in hypoendemic areas of the Dnieper and Northern Dvina basins exceeded those of the disease rate. Causes of this phenomenon are discussed. Double serological screening of population in the foci performed in summer-autumn and spring seasons demonstrated a considerable increase in infestation rate parameters in autumn and their decrease in spring. Seasonal character of infestation is better expressed in the mesoendemic areas than in the hyperendemic ones. Infestation and disease rates are discussed for various age groups in different areas.
Assuntos
Reservatórios de Doenças , Opistorquíase/epidemiologia , Fatores Etários , Animais , Anticorpos Anti-Helmínticos/análise , Fezes/parasitologia , Água Doce , Humanos , Técnicas Imunoenzimáticas , Opistorquíase/diagnóstico , Opistorquíase/parasitologia , Opisthorchis/imunologia , Estações do Ano , Testes Sorológicos , U.R.S.S. , População UrbanaRESUMO
An indirect method for the determination of antibodies to Opisthorchis antigens has been used in the elaboration of enzyme immunoassay for opisthorchiasis diagnosis. A visual method for the assessment of the results has been suggested. Its diagnostic efficacy has been determined. With the study of 1722 sera of the control subjects, the test specificity was 97.5%. Test sensitivity in the acute stage of the disease (40 patients) was about 100%, in the chronic stage (435 patients) it depended on oocyst production by the parasite. With less than 10 oocysts per I g feces, test sensitivity did not exceed 34.3%, with more than 1000 oocysts per I g feces it reached 94.4%. Mass population screenings, using the test in question, in 2 opisthorchiasis foci with different levels of endemia have shown that their results correspond to the data of copro-ovoscopy. The use of the test is most promising for the diagnosis of early phase of opisthorchiasis and the assessment of epidemiological situation in the foci.
Assuntos
Opistorquíase/diagnóstico , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Estudos de Avaliação como Assunto , Fezes/parasitologia , Humanos , Técnicas Imunoenzimáticas , Opistorquíase/epidemiologia , Opistorquíase/imunologia , Opisthorchis/imunologia , Contagem de Ovos de Parasitas , Estudos SoroepidemiológicosRESUMO
The paper describes how enzyme immunoassay (EIA) and copro-ovoscopy are concurrently used to define the spread of clonorchiasis among the population of the Nanaisk District in the Khabarovsk Territory. It shows the efficiency of EIA in seroepidemiological surveys and the possibility of its use in endemic areas. The sensitivity of EIA to determine antibodies to Clonorchis antigens was 70.58% and its specificity was 98.4%. The assay is recommended for wide application in clinical and epidemiological practice in the foci of the disease. The total affliction of the population, which was calculated by 2 techniques is 33.7% +/- 3.0.
Assuntos
Clonorquíase/diagnóstico , Fezes/parasitologia , Adulto , Animais , Anticorpos Anti-Helmínticos/sangue , Criança , Clonorquíase/epidemiologia , Clonorchis sinensis/imunologia , Reservatórios de Doenças , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Contagem de Ovos de Parasitas/métodos , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Sibéria/epidemiologiaRESUMO
The imago stage of Echinococcus multilocularis development (prior to maturation of parasite oocysts) has been described in the intestine of golden hamsters infected by parenteral penetration of an Alveococcus agent and given hydrocortisone subcutaneously for 3 days before the infection and on the day of the infection, mean total drug dose being about 250 mg/kg. The number of helminths developed on days 8-35 of postinvasion ranged from 432 to 1863, their length was 1.0 to 4.0 mm and the number of segments did not exceed 2. Oocyst maturation was noted on day 20 of postinvasion. High oocyst invasiveness was confirmed by a biological test on 32 cotton rats aged 1-1.5 months who were administered parenterally 2-3 helminths containing 86 to 284 oocysts. All the rats died of severe hepatic alveococcosis on days 24-43 of postinfection.
Assuntos
Modelos Animais de Doenças , Equinococose/parasitologia , Enteropatias Parasitárias/parasitologia , Mesocricetus/parasitologia , Animais , Cricetinae , Echinococcus/isolamento & purificação , Feminino , Intestino Delgado/parasitologia , Masculino , Sigmodontinae/parasitologia , Fatores de TempoRESUMO
An enzyme immunoassay with homologous and heterologous antigens has been elaborated for the diagnosis of clonorchiasis. 251 blood serum samples from patients with clonorchiasis have been studied, as well as 230 samples from patients with geohelminthiases obtained from North Vietnam provinces and 299 samples from Moscow donors. The test sensitivity and specificity were 78.72% and 94.52%, respectively. The dependence of test sensitivity on the intensity of infection has been noted. The calculation of the diagnostic value of enzyme immunoassay makes it possible to use it with respect to the level of the population invaxon: in low level of invaxon (below 32%) D = 2.11M + 0.06, in invaxon level above 32%, D = 1.74M + 0.04. The use of a homologous antigen enhances the test sensitivity.