ABSTRACT
Parasitological examinations were carried out on 663 individuals of three different cities of Pernambuco State, Northeastern Brazil: Recife, Palmares and Bodocó. The population from a drought area of Pernambuco State, Bodocó, was investigated for amoebiasis and compared with Recife, metropolitan city (about 1.3 million of inhabitants) and another inland community, Palmares, located inside of the sugar-cane plantation region of the State. No evidence of invasive strains of E. histolytica were found in these inhabitants, provided that the isolated zymodemes I, III, IV, VIII, IX, X, XVII and XVIII are recognized as nonpathogenic strains of E. histolytica. Furthermore, the prevalence of intestinal helminths and other protozoan infections showed that these individuals are infected by other agents responsible for diarrhoeal diseases.
Subject(s)
Dysentery, Amebic/epidemiology , Entamoeba histolytica/pathogenicity , Adolescent , Adult , Animals , Brazil/epidemiology , Child , Child, Preschool , Feces/parasitology , Female , Humans , Infant , Infant, Newborn , Intestinal Diseases, Parasitic/epidemiology , Male , Prevalence , Protozoan Infections/epidemiologySubject(s)
Entamoeba histolytica/enzymology , Isoenzymes/analysis , Adolescent , Animals , Brazil , Child , Child, Preschool , Feces/parasitology , Female , Humans , MaleABSTRACT
The pathogenicity of 47 strains of Entamoeba histolytica isolated in Pernambuco, Brazil, was examined using the polymerase chain reaction (PCR) followed by restriction-endonuclease digestion. Electrophoretic patterns of PCR products digested with HinfI revealed that all strains were nonpathogenic. The results were entirely in accord with phenotypic properties such as isoenzyme patterns and the failure to bind a pathogenic-isolate-specific monoclonal antibody. When the sensitivity of PCR was examined, amplified products could be detected from template DNA equivalent to five trophozoites. These observations indicate that PCR amplification of genomic DNA and subsequent restriction-enzyme digestion is a useful strategy for obtaining a sensitive and accurate diagnosis. The present study also demonstrates that nonpathogenic strains of E. histolytica predominate in northeastern Brazil.
Subject(s)
DNA, Protozoan/analysis , Entamoeba histolytica/pathogenicity , Entamoebiasis/parasitology , Animals , Base Sequence , Brazil , Deoxyribonucleases, Type II Site-Specific , Entamoeba histolytica/classification , Entamoeba histolytica/enzymology , Entamoeba histolytica/genetics , Humans , Isoenzymes/analysis , Molecular Sequence Data , Polymerase Chain Reaction , Restriction Mapping , Sensitivity and SpecificityABSTRACT
Parasitological examinations were carried out during July to December, 1989, on 485 inhabitants of four villages in São Lourenço da Mata, 25 km northwest of Recife, Pernambuco, Brazil. Approximately 99.6% of the inhabitants were infected with at least one species of intestinal parasites. A high prevalence of Schistosoma mansoni (82.1%), hookworm (80.2%) Trichuris trichiura (69.9%), Ascaris lumbricoides (61.9%) and Entamoeba coli (36.7%) infections were demonstrated. Test tube cultivation revealed that the most common species of hookworm in this region was Necator americanus (88.4%), and also that the prevalence of Strongyloides stercoralis was 5.8%. Three hundred and thirty-four sera were serologically examined for amoebiasis by the gel diffusion precipitation test (GDP) and enzyme-linked immunosorbent assay (ELISA). No positive reaction was observed in all sera as examined by GDP, while 24 sera were positive by ELISA.
Subject(s)
Dysentery, Amebic/epidemiology , Intestinal Diseases, Parasitic/epidemiology , Adolescent , Adult , Brazil/epidemiology , Child , Child, Preschool , Dysentery, Amebic/diagnosis , Enzyme-Linked Immunosorbent Assay , Feces/parasitology , Female , Humans , Immunodiffusion , Infant , Intestinal Diseases, Parasitic/diagnosis , Male , Middle Aged , Prevalence , Rural HealthABSTRACT
Entre fevereiro e junho de 1989, investigaram-se 126 crianças diarréicas e 126 controles, pareados pela idade, para a detecçäo de bactérias, vírus e parasitos enteropatogênicos. Identificaram-se um ou mais patógenos em 81,8% dos pacientes e em 61,9% dos controles. Escherichia coli enteropatogênica(EPEC) foi o patógeno mais frequentemente identificado. EPEC mostrando aderência localizada, E.coli enteroaderente agregativa, Shigella, Rotavírus e Cryptosporidium foram associados com os casos significativamente. Por outra parte, EPEC näo aderente, E.Coli exibindo aderência difusa, E.coli enterotoxigênica (ETEC) produtora de LT, Salmonella, Campylobacter, Adenovírus, Giardia lamblia e Endamoeba histolytica näo mostraram diferenças significativas entre casos e controles. ETEC produtoras de ST,E.coli enteroinvasiva e enterohemorrágica, Aeromonas, Pleisaomonas e Vibrio foram isolados em taxas muito baixas para permitir avaliar seus papéis na doenças diarréica, no Recife