ABSTRACT
Introduction: Entamoeba histolytica infections were investigated in residents of the Ariquemes and Monte Negro municipalities in Rondônia State, Brazil. Methods: Stool samples of 216 individuals were processed by the spontaneous sedimentation method and analyzed by microscopy for detection of the E. histolytica/E. dispar complex, followed by the immunoassay method using an enzyme-linked immunosorbent assay-based kit for the E. histolytica stool antigen. Results: E. histolytica/E. dispar cysts were present in 61% (50/82) and 44% (59/134) of the samples from Ariquemes and Monte Negro respectively, with a significant difference in the occurrence of infection between the two populations [p < 0.05; χ2 = 5.2; odds ratio = 2.0 (1.1 - 3.6)]. The E. histolytica antigen detection rate was 36.6% (30/82) for stool samples from Ariquemes, and 19.4% (26/134) for stool taken from the residents of Monte Negro. The rate of the occurrence of amoebiasis was significantly higher in the population from Ariquemes [p < 0.05; χ2 = 7.8; odds ratio = 2.4 (1.2 - 4.7)]. Discussion: Due to the high occurrence of E. histolytica infected residents diagnosed in the region and the unavailability in local clinics of a test to distinguish between the two Entamoeba species, physicians should consider treating E. histolytica/E.dispar infections. Conclusion: The results indicate that E. histolytica infection is highly endemic in the studied areas. .
Introdução: Infecções por Entamoeba histolytica foram investigadas em moradores dos municípios de Ariquemes e Monte Negro, Rondônia, Brasil. Métodos: Amostras de fezes de 216 indivíduos foram processadas por microscopia óptica para detecção de cistos do complexo E. histolytica/E. dispar, seguido pelo método de imunoensaio utilizando kit de ensaio imunoenzimático para detecção específica de antígeno de E. histolytica. Resultados: Cistos de E. histolytica/E. dispar estavam presentes em 61% e 44% das amostras de Ariquemes e Monte Negro, respectivamente com diferença significativa na ocorrência da infecção entre as duas populações [p < 0,05; χ2 = 5,2; Odds relativa = 2,0 (1,1 - 3,6)]. A taxa de detecção de antígenos de E. histolytica nas amostras provenientes de Ariquemes foi de 36,6% e de 19,41% nas amostras de Monte Negro, sendo a ocorrência de amebíase significativamente maior na população de Ariquemes [p < 0,05; χ2 = 7,8; Odds relativa = 2,4 (1,2 - 4,7)]. Discussão: A elevada frequência da infecção por E. histolytica em residentes na região, bem como a indisponibilidade de avaliação clínica por testes específicos para distinção entre as duas espécies de Entamoeba, deve promover uma reflexão sobre o tratamento de infecções pelo complexo E. histolytica/E. dispar. Conclusão: Nas populações avaliadas foram detectadas elevadas ocorrências de E. histolytica. .
Subject(s)
Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Young Adult , Entamoeba histolytica/isolation & purification , Entamoebiasis/epidemiology , Antigens, Protozoan/immunology , Brazil/epidemiology , Enzyme-Linked Immunosorbent Assay , Entamoeba histolytica/immunology , Entamoebiasis/diagnosis , Feces/parasitology , Prevalence , Risk Factors , Urban PopulationABSTRACT
Introduction The aim of this work was to identify possible lymphatic filariasis foci in the western Brazilian Amazonian that could be established from the reports of Rachou in the 1950s. The study was conducted in three cities of the western Brazilian Amazon region - Porto Velho and Guajará-Mirim (State of Rondônia) and Humaitá (State of Amazonas). Methods For human infection evaluation thick blood smear stained with Giemsa was used to analyze samples collected from 10pm to 1am. Polymerase chain reaction (PCR) was used to examine mosquito vectors for the presence of Wuchereria bancrofti DNA. Humans were randomly sampled from night schools students and from inhabitants in neighborhoods lacking sanitation. Mosquitoes were collected from residences only. Results A total 2,709 night students enrolled in the Program for Education of Young Adults (EJA), and 935 people registered in the residences near the schools were examined, being 641 from Porto Velho, 214 from Guajará-Mirim and 80 from Humaitá. No individual examined was positive for the presence of microfilariae in the blood stream. A total of 7,860 female Culex quinquefasciatus specimens examined were negative by PCR. Conclusions This survey including human and mosquito examinations indicates that the western Amazon region of Brazil is not a focus of Bancroftian filariasis infection or transmission. Therefore, there is no need to be included in the Brazilian lymphatic filariasis control program. .