RESUMO
Congenital Chagas disease (CChD) has been reported in different countries, mostly in Latin America. In 1987 a fatal case of CChD of second generation (CChDSG) was published. Within a period of six months--1989-1990--two cases of CChDSG were diagnosed and studied in the city of Santiago. Two premature newborns, sons of two sisters, with moderate liver and spleen enlargement, were found to have positive serology for Chagas disease and xenodiagnoses. The mothers, urban residents all their lives, without antecedents of triatomine bugs contact or blood transfusions, showed positive serology and xenodiagnoses. Their mother (grandmother of the infants), lived 20 years in a Northern rural Chagas disease endemic locality, in a triatomine infested house. Afterwards, she moved to Santiago, where she married and has resided up to now. Serology and xenodiagnoses were also positive. All the Trypanosoma cruzi infected individuals were successfully treated with nifurtimox.
Assuntos
Doença de Chagas/congênito , Doença de Chagas/diagnóstico , Criança , Chile , Humanos , Recém-Nascido , Recém-Nascido Prematuro , MasculinoRESUMO
Chagas disease is widespread in Chile, distributed in rural and periurban areas in the 7 most northern regions of the country. The principal vector of Trypanosoma cruzi is Triatoma infestans. The interruption of the domestic cycle of transmission of T. cruzi has been attempted by health education, human housing improving, and elimination of the vector by means of systematic insecticide spraying of human dwellings. Spraying with insecticides has been supported by Chile's health authorities and has been carried out for the last 12 years. A total of 13,280 children (aged up to 10 years) were randomly selected from 47 counties in the area of Chile endemic for Chagas disease, and blood samples were collected to determine the levels of antibodies to T. cruzi by indirect hemagglutination and enzyme-linked immunosorbent assay tests. The results of the tests were analyzed to determine the changes that occurred after 12 years of insecticide spraying of dwellings to eliminate T. infestans infestation. A total of 142 (1.1%) samples of children showed antibodies to T. cruzi. This rate is significantly lower than the data generated in similar studies conducted in 1982-1985. The following reduction in prevalence rates were observed in each of the 7 endemic regions of the country: region I, 5.5-0.3%; region II, 6.6-0.3%; region III, 9.8-1.0%; region IV, 7.2-2.0%; region V, 5.2-1.9%, Metropolitan region, 1.4-0.6%; and region VI, 1.4-0.4%. Serovigilance of T. cruzi antibodies level represents a novel approach that may allow the evaluation of the impact of the vector elimination program. The results identify regions that need to strengthen the efforts to reduce the insect infestation of dwellings.
Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/prevenção & controle , Insetos Vetores , Triatoma , Trypanosoma cruzi/imunologia , Animais , Doença de Chagas/epidemiologia , Criança , Pré-Escolar , Chile/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Testes de Hemaglutinação , Humanos , Lactente , Recém-Nascido , Inseticidas , Masculino , Prevalência , Serviços Preventivos de Saúde , Saúde da População RuralRESUMO
Fifty samples of cereals including 30 of wheat (10 of wheat hard red spring), 10 of wheat soft red winter and 10 of wheat durum ámber), 10 of barley and 10 of corn (5 of white corn and 5 of yellow corn) were analyzed to detect and determine by the TLC method, the quantity of deoxynivalenol levels, which is a toxic secondary metabolite produced by Fusarium species. The aw of samples and the internal and external micoflora and Fusarium spp. levels were also investigated. Results showed that the highest grade of infection (12-80%), and the highest count of total molds (3.9 Log UFC/g) were detected in wheat samples, while the highest levels of Fusarium spp. (2.3 Log UFC/g) were detected in white corn. Deoxynivalenol was found in the wheat and barley samples but not in corn. The wheat red winter soft samples showed the highest levels of deoxynivalenol (3.2 ug/g) which is over the limit levels accepted by the FDA. Correlation was not found among count of total molds, Fusarium spp., infestation grade, aw, and deoxynivalenol levels. These results suggest that it is necessary to exert measures to avoid and to control the importation of contaminated cereals with DON levels higher to those allowed.
Assuntos
Grão Comestível/química , Grão Comestível/microbiologia , Fusarium/isolamento & purificação , Tricotecenos/análise , Animais , Conservação de Alimentos/métodos , Humanos , Tricotecenos/isolamento & purificação , Microbiologia da ÁguaRESUMO
Toxoplasmosis, a world-wide zoonotic infection, is generally asymptomatic and benign in immunocompetent individuals, but it can be serious in immunodeficiencies particularly in patients with acquired immunodeficiency syndrome and in children infected in utero. So, it is important to dispose methods which permit discriminate between recent and chronic infections. In order to contribute to improve the diagnosis of toxoplasmosis ELISA IgG, IgM, IgA and ELISA IgG avidity were performed in 15 and 24 sera from patients suspected of having acute and chronic infection respectively, according dye test (DT) titres. ELISA IgG was positive in both groups, ELISA IgM was positive in 78.6 and 58.3% respectively, while ELISA IgA was positive in 85.7 and 33.3% of recent and chronic group respectively. In those sera with low IgG avidity (18.8%) we found specific IgM in 71.5 and 4.2% and IgA in 78.6 and 0.0% of recent and chronic groups respectively. Parallelling, 208 sera samples were classified according to the results of DT, indirect hemagglutination and complement fixation tests in the following groups: acute (97), intermediate (36), chronic (35) and negative (40). The results were: acute (96.9-64.9-55.6 and 65.9%); intermediate (97.2-63.8-44.4 and 47.2%); chronic (45.7-42.8-5.7 and 34.3%) for IgG, IgM, IgA and low IgG avidity respectively. The use of both acute markers, IgA and low IgG avidity in the diagnosis of toxoplasmosis is discussed.
Assuntos
Afinidade de Anticorpos , Ensaio de Imunoadsorção Enzimática/métodos , Toxoplasma/imunologia , Toxoplasmose/diagnóstico , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/sangue , Distribuição de Qui-Quadrado , Doença Crônica , Testes de Fixação de Complemento , Hemaglutinação , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Toxoplasmose/sangueRESUMO
Evaluation of desinsectation programs carried out in the two Health Services from the V Region, was undertaken by comparing serologic prevalences of T. cruzi infection age groups exposed to the risk of infection in rural areas during the antivectorial campaign activities (1982 vs 1995). Thus, were studied 2,193 blood samples from children under 10 years of age, proceeding from six chagasic endemic provinces in which antitriatomic domiciliary insecticide sprayings had been performed. Indirect hemagglutination and ELISA tests were carried out to each of the blood samples. A total de 42 (1.9%) children resulted positive. As in five counties no positive cases were detected in the last five years it is possible to assume that vector transmission of T. cruzi should have been interrupted in them. When comparing prevalences existing in 1982 with the present ones, it is possible to observe a 63.5% of reduction of transmission in the V Region, been this reduction higher in the Aconcagua Health Service with 79.6% and lower in the Viña del Mar--Quillota Health Service with 55.6%. According to these results, comparison of prevalence of T. cruzi infection in children less than 10-year-old in diverse periods, allows evaluate the vectorial control of Triatoma infestans programs.
Assuntos
Anticorpos Antiprotozoários/sangue , Doença de Chagas/epidemiologia , Trypanosoma cruzi/imunologia , Animais , Doença de Chagas/sangue , Doença de Chagas/diagnóstico , Criança , Pré-Escolar , Chile/epidemiologia , Humanos , Lactente , Recém-Nascido , Prevalência , Fatores de Risco , População Rural , Estudos SoroepidemiológicosRESUMO
During 1997 a seroepidemiological study on Chagas' disease was carried out in 18 localities of three provinces (Tocopilla, El Loa and Antofagasta) of Region II (20 degrees 56'-26 degrees South Lat.; 70 degrees 38'-67 degrees West Long.), in order to assess the impact of the control program against Triatoma infestans launched in 1988, based on insecticide spraying of dwellings. By means of ELISA and an indirect hemagglutination test for Chagas' disease blood samples from 1,034 children under 10 years of age were examined, arising a 0.5% (3 cases) positivity. Test resulted positive in 2 (0.9%) children from the locality of San Pedro de Atacama and 1 (0.4%) from Calama city, all in the age group 6-10 year-old. However, none of their dwellings were found infested with T. infestants. These results indicate that the control program has a good possibility to prevent new human infections. It is advisable to continue the seroepidemiological and entomological vigilance and remark the necessity of increasing the effort in the study of transmission through other routes, to adopt or reinforce the pertinent preventive measures.
Assuntos
Doença de Chagas/epidemiologia , Doenças Endêmicas , Adulto , Doença de Chagas/diagnóstico , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Avaliação de Programas e Projetos de Saúde , Estudos SoroepidemiológicosRESUMO
A serological survey was carried out in Osorno X Region, Chile (40 degrees 21'-40 degrees 46' South lat, and 73 degrees 26' -72 degrees-46' West long.). An indirect hemagglutination test (IHAT) for toxoplasmosis was performed to 305 persons--160 blood donors and 145 with sexually transmitted disease (STD). The age of the surveyed persons (167 males and 138 females) varied between 10 and 72 years. IHAT titers > 16 were considered as positive. The general prevalence was 20.3%--21.2% in blood donors and 19.3% in persons with some STD--with no differences between males and females. However, significant differences between males and females with STD were found (35.6% and 8.1% respectively). No differences between urban and rural inhabitants were found with a slight higher prevalence in the urban ones. No antibodies against Toxoplasma gondii were detected in six AIDS patients. The importance of performing toxoplasmosis immunodiagnosis and individual prophylaxis to avoid the infection in high risk group are recommended.
Assuntos
Infecções Sexualmente Transmissíveis/epidemiologia , Toxoplasmose/epidemiologia , Síndrome da Imunodeficiência Adquirida/sangue , Síndrome da Imunodeficiência Adquirida/epidemiologia , Adolescente , Adulto , Idoso , Anticorpos Antiprotozoários/sangue , Doadores de Sangue , Criança , Chile/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Soroepidemiológicos , Distribuição por Sexo , Infecções Sexualmente Transmissíveis/sangue , Infecções Sexualmente Transmissíveis/complicações , Toxoplasmose/complicaçõesRESUMO
Chile is located in the southwestern border of South America. The country is 4,329 km long and 96-342 wide. From north to south it is divided into five marked different biogeographical zones: deserts, steppes, bushes, forests (cattle raising) and austral (sheep raising). Population (June 1999) 15,017,760 (14.6% rural). Human hydatidosis is endemic in Chile. According to Ministry of Health information about 320 cases are registered each year. In order to find out the likely prevalence of human hydatidosis in Chile, a series of serosurveys was carried out in 1988-1997 throughout the total country. By using the indirect hemagglutination reaction and ELISA for hydatidosis (tests with good sensibility and specificity) 60,790 unselected apparently healthy persons: 41,399 from urban areas (16,428 blood donors, 13,894 delivering mothers and 11,077 middle grade schoolchildren) and 19,361 from rural areas--from randomly selected family groupings--were studied. A total individuals 82 (136/100,000) resulted positive: 36 (87/100,000) urban and 46 (241/100,000) rural, being the prevalence higher in rural areas, particularly in the southern austral zone (mean 1068/100,00). These figures agree with those observed in clinical epidemiological studies. In conformity with the present results, in the whole country 17,002 individuals should have hydatidosis: 10,318 urban and 6,784 rural. All these possible infected people, not necessarily should present pathology in the future, as it has been observed in autopsies from unselected individuals, performed at the Medico-Legal Service in Santiago, in whom 71.3% of diagnosed hydatosis with hydatid cysts in many different locations, was an autopsy finding.
Assuntos
Equinococose/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Saúde da População Rural/estatística & dados numéricos , Estudos Soroepidemiológicos , Distribuição por Sexo , Saúde da População Urbana/estatística & dados numéricosRESUMO
An ELISA test for trichinosis using as antigen a larvae soluble fraction from Trichinella spiralis was carried out for the detection of IgM and IgA specific antibodies in 45 serum samples from patients confirmed or suspected to have trichinosis by strong clinical and epidemiological evidences. All the patients had positive serology detected by precipitin test, bentonite floculation test, indirect hemagglutination test and ELISA IgG test. The cut-off value was determined using two criteria. Criterion A was determined in each plate, using three positive controls and two negative ones; the average of the negative controls and the weakest positive control, multiplied by a 1.2 factor was, considered the cut-off value. Criterion B was determined using the average plus three standard deviations from 64 apparently healthy persons serum samples. In both cases, three serum dilutions (1:10, 1:100 and 1:500) were used. The sensitivity of ELISA IgM was 100.0, 93.3 and 82.2% using serum dilutions of 1:10, 1:100 and 1:500 respectively (criterion A) and 100.0, 97.8 and 95.6% for the same dilutions (criterion B), whereas the values for ELISA IgA were: 100.0, 91.1 and 86.7% (criterion A) and 100.0, 100.0 and 91.1% (criterion B). In order to find out the specificity of ELISA IgM and ELISA IgA, additional 118 serum samples from individuals with other parasitoses, such as cysticercosis (18) hydatidosis (39), fascioliasis (12), toxocariasis (30), Chagas' disease (12) and individuals with non-specific eosinophilia (7), were also tested. ELISA IgM presented a specificity of 92.3, 93.4 and 97.3% (criterion A) and 96.2, 97.8 and 97.8% (criterion B) whereas the results for ELISA IgA were 97.8, 98.9 and 99.4% (criterion A) and 98.4% for the 1:10 and 1:100 dilutions and 100.0% for the 1:500 dilution (criterion B). The positive predictive values of ELISA IgM were 76.3, 77.8 and 88.1% (criterion A) and 86.5, 91.7 and 91.5% (criterion B) whereas the negative ones were 100.0, 98.3 and 95.7% (criterion A) and 100.0, 99.4 and 98.9% (criterion B). The positive predictive values of ELISA IgA were 91.8, 95.3 and 97.5% (criterion A) and 93.8, 93.8 and 100.0% (criterion B) whereas the negatives ones were: 100.0, 97.8 and 96.8% (criterion A) and 100.0, 100.0 and 97.8% (criterion B). The use of ELISA IgM and ELISA IgA in the immunodiagnosis of trichinosis is discussed.
Assuntos
Antígenos de Helmintos , Ensaio de Imunoadsorção Enzimática/normas , Imunoglobulina A/imunologia , Imunoglobulina M/imunologia , Trichinella spiralis/imunologia , Triquinelose/diagnóstico , Adulto , Animais , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Valor Preditivo dos Testes , Sensibilidade e EspecificidadeRESUMO
Amplification by the polymerase chain reaction (PCR) of Trypanosoma cruzi kinetoplastic DNA was used to enhance sensitivity in the detection of the parasite in blood, with the ultimate goal of improving the parasitological diagnosis of Chagas' disease in 0-10 year-old infected children. Twenty eight children were evaluated by using xenodiagnosis (XD) and PCR. Whereas XD detected 75.0% of the cases PCR was positive in 96.8%. The usefulness of the PCR was further investigated in the 28 children who have received specific treatment with nifurtimox. Negativation of XD after three and six months post treatment was observed in all the cases, but only 21.4% and 35.8% negativation of the PCR after three and six months post treatment respectively. These observations suggest that PCR is the most sensitive and quick technique available for direct detection of T. cruzi in chagasic children and that it can be a very useful tool for the follow-up of infected subjects after specific chemotherapeutical treatment.
Assuntos
Doença de Chagas/diagnóstico , DNA de Protozoário/isolamento & purificação , Nifurtimox/uso terapêutico , Reação em Cadeia da Polimerase , Doença de Chagas/sangue , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Criança , Pré-Escolar , Estudos de Avaliação como Assunto , Humanos , Lactente , Recém-Nascido , Sensibilidade e EspecificidadeRESUMO
Though Toxoplasma gondii can cause severe pathology in human, in most of the cases it produces only asymptomatic infection. So, it is important to dispose some methods capables to discriminate between acute and chronic infections. An indirect hemagglutination test (IHAT), dye test (DT) and complement fixation test (CFT) were performed in 647 sera from patients suspected of having toxoplasmosis infection. IHAT and DT titer > or = 4 and CFT > or = 5 were considered positive. Titers were classified as follows: low (4-16), median (64-512) and high (> or = 1000) for IHAT and DT. The pathologies for demanding these serological tests were: adenopathies (58), nephropathies (72), neuropathies (30), obstetrical problems (65), opthalmopathies (147), AIDS (237) and miscellaneous (37). Global positivity of 49.5% and 4.5% for IHAT/DT and CFT respectively were found. The positivity for the different groups were: adenopathies (48.3% and 13.8%), nephropathies (43.1% and 1.4%), neuropathies (26.7% and 3.3%), obstetrical problems (40.0% and 0.0%), ophthalmopathies (59.9% and 8.2%), AIDS (52.1% and 2.5%) and miscellaneous (40.5% and 2.7%) for IHAT/DT and CFT respectively. Low and median titers for IHAT/DT were found in 81.3% of cases. A high agreement in frequency of concordant and discordant titers of IHAT/DT and CFT, indicating a recent or acute infection was observed. This fact was more relevant in adenopathies, ophthalmopathies (uveitis) and AIDS groups.
Assuntos
Toxoplasmose/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Testes Imunológicos , Lactente , Masculino , Pessoa de Meia-IdadeRESUMO
Surveillance of the epidemiology of human trichinosis in Chile has been maintained during the last 30 years by the Department of Parasitology. Incidence and prevalence have been followed-up by analysing Ministry of Health annual reports and periodical phototrichinoscopic examination of diaphragm samples from individuals autopsied at the Santiago Medico Legal Service. A decrease has been observed on: incidence from 1.4 per 100,000 in the 1960s to 0.7 in the 1980s down to 0.3 in 1993 and 1994 and to 0.5 in 1995, and prevalence from 3.4% to 2.8%, 2.0% and 0.8% in 1972, 1982, 1992 and 1997 respectively. A predominance of the prevalence in the groups of more age, with the observation of calcified Trichinella spiralis larvae should be indicating a decline of new infections in the general population. This decrease of frequency of human trichinosis in Chile is possible due to the interaction of two main factors, efficacy and higher implementation of control measures and significant advances in porcine technology with a resulting provision to consumers of pork from young animals practically trichinosis free.
Assuntos
Triquinelose/epidemiologia , Adolescente , Adulto , Idoso , Animais , Cadáver , Criança , Pré-Escolar , Chile/epidemiologia , Diafragma/parasitologia , Humanos , Incidência , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Prevalência , Trichinella spiralis/isolamento & purificaçãoRESUMO
An analysis of immunodiagnosis data for human neurocysticercosis (NC) by ELISA-IgG, complement fixation test (CFT) and indirect hemagglutination test (IHAT) in 67 serum samples and 54 cerebrospinal fluids (CSF) from confirmed cases of different hospitals from the Metropolitan Area of Santiago, Chile, was performed. The cut-off value was determined by using serum samples from 60 apparently healthy persons, whose absorbance values were the mean plus three standard deviations. The sensitivity of ELISA was 97.0% and 100% for serum samples and CSF respectively. This assay was considered of statistical significance (p < 0.05) when it was compared with CFT. Specificity was established by testing a purified antigen over 109 different helminthiasis serum samples, 185 neurological affections other than NC and 60 control samples. A 98.3% of global specificity was found. The use of ELISA-IgG and a purified antigen in the approach of immune diagnosis of NC is considered a useful assay, particularly if it is performed on paired serum/CSF samples.
Assuntos
Antígenos de Helmintos/imunologia , Doenças do Sistema Nervoso Central/diagnóstico , Cisticercose/diagnóstico , Cysticercus/imunologia , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/imunologia , Animais , Doenças do Sistema Nervoso Central/sangue , Doenças do Sistema Nervoso Central/líquido cefalorraquidiano , Doenças do Sistema Nervoso Central/imunologia , Testes de Fixação de Complemento , Cisticercose/sangue , Cisticercose/líquido cefalorraquidiano , Cisticercose/imunologia , Humanos , Sensibilidade e EspecificidadeRESUMO
Chagas' disease is a parasitic zoonosis with high prevalence in Chile. It is distributed in rural and periurban section in the northern most seven out of thirteen regions in which the country is divided, and affects about 142,000 individuals dispersed in most of the 165 counties sited in the chagasic zone. Triatoma infestans--intradomiciliary species--is the main and practically exclusive vector of Trypanosoma cruzi. Diverse tools may be utilized in order to interrupt the domestic cycle of transmission of T. cruzi: health education, housing improvement and elimination of vectors by dwelling insecticide sprayings. This last resource has received priority in Chile in the last 12 years. To evaluate the effectivity of the programs for eliminating T. infestans a serological study for Chagas' disease--comprising 8,767 children less than 10 years old from 27 rural counties insecticide sprayed in the last 12 years--was carried out. A global total of 125 (1.4%) children resulted positive, figure significantly lower than 5.4% found in 1982-1990 in the same age group. Distribution by regions of positive individuals showed a decrease of prevalence in each of them: III Region, from 9.8 to 1.0%, IV Region, 7.2 to 2.0%, V Region, 5.2 to 1.9%, and Metropolitan Region, 1.4% to 0.6. Even though positive children have still been found in 46.7% of localities of the studied counties, it is possible to affirm that the vector control programs have been effective and must be maintained, and increased in those localities with T. cruzi infection in children under 10 years of age, with the general aim of eradicate Chagas' disease transmission in Chile before 2000.
Assuntos
Doença de Chagas/epidemiologia , Doença de Chagas/prevenção & controle , Insetos Vetores , Triatoma , Animais , Doença de Chagas/sangue , Criança , Pré-Escolar , Chile/epidemiologia , Humanos , Lactente , Recém-Nascido , Prevalência , Avaliação de Programas e Projetos de Saúde , Trypanosoma cruzi/isolamento & purificaçãoRESUMO
A control program of Triatoma infestans has been carried out in Alto del Carmen, an endemic chagasic rural county in the III Region, Chile. The program started in 1988 with an attack phase consisting in a masshouse spraying with residual insecticide, followed by an entomological surveillance phase with health education for community participation and vector detection in eventually reinfested houses. A yearly evaluation in 1992, 1993, 1994 and 1995 was carried out in order to determine the effectiveness of vector control activities. In 1992, 24.1% of dwellings was infested, whereas in 1993, 1994 and 1995 the infestation rates were 3.9%, 2.8% and 4.0% respectively. The similar infestation rates found in 1993, 1994 and 1995 suggest passive dispersion of triatomas from areas without surveillance. Additionally, in 1994, 110 (16.0%) out of 688 examined people resulted serologically positive. It is noteworthy that all of the children in the 0-4 year age group--born after the attack phase--resulted serologically negative. This fact may indicate the interruption of vectorial transmission of Chagas' disease in Alto del Carmen county. It is concluded that the control activities performed in the county constitute good strategies to the Nacional Program of Control of T. infestans, but for the success of such a program it is necessary to integrate the efforts of all endemic areas with an active community participation.
Assuntos
Doença de Chagas/prevenção & controle , Controle de Insetos , Insetos Vetores , Triatoma , Adolescente , Adulto , Animais , Doença de Chagas/sangue , Doença de Chagas/transmissão , Criança , Pré-Escolar , Chile , Humanos , Lactente , Recém-Nascido , Insetos Vetores/parasitologia , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Triatoma/parasitologia , Trypanosoma cruzi/isolamento & purificaçãoRESUMO
We have investigated the prevalence of antibodies against Toxoplasma gondii, Trypanosoma cruzzi, Hepatitis B virus, cytomegalovirus, rubella virus, and human immunodeficiency virus in 139 adolescent pregnant women and in their high risk newborn children. The methods employed were the Sabin and Feldman reaction, complement fixation reaction, ELISA, and xenodiagnostic 30.9% of the pregnant group were seropositive for T. gondii, both mothers and newborns were IgM-negative. Two mothers (1.4%) presented anti T. cruzii antibodies, and one newborn child had circulating parasites. Related to the virological studies, 93.5% of the population were anti CMV antibodies positive and all their newborns were IgM (-) 90.6% of the adolescents were rubella positive and one was seropositive to VIH. We conclude that the prevalence found in this group of adolescent pregnant women are not significantly different to the one reported for the general pregnant women population.
Assuntos
Complicações Infecciosas na Gravidez , Adolescente , Adulto , Biomarcadores/sangue , Chile , Infecções por Citomegalovirus/diagnóstico , Feminino , Sangue Fetal/parasitologia , Sangue Fetal/virologia , Seguimentos , Humanos , Recém-Nascido , Masculino , Gravidez , Complicações Infecciosas na Gravidez/sangue , Complicações Infecciosas na Gravidez/diagnóstico , Fatores de Risco , Toxoplasmose/diagnósticoRESUMO
An analytical study of positive xenodiagnosis (XD), according to age distribution, in people with a positive indirect hemagglutination test (IHAT) for Chagas' disease has been carried out. A total of 1,137 IHAT for Chagas' disease positive persons were submitted to two wooden XD boxes containing 7 Triatoma infestans nymphs III each. The positivity (%) of XD in the different age groups was: 0-9 year-old (60.8), 10-19 (35.8), 20-29 (31.5), 30-39 (28.7), 40-49 (30.0), 50-59 (34.3) and > or = 60 (43.3). The 60.8% positivity of XD in children under 10 years of age is possibly due to the rather recent Trypanosoma cruzi infection in this age group and to diverse immunological mechanisms, which decrease with the age increasing.
Assuntos
Doença de Chagas/diagnóstico , Adolescente , Adulto , Fatores Etários , Animais , Doença de Chagas/parasitologia , Criança , Pré-Escolar , Doença Crônica , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Parasitologia/métodosRESUMO
The IV Region (29 degrees 30'-32 degrees 13' south lat.) is located in the center of the geographical area of distribution of Chagas' disease in Chile. Triatoma infestans is the main and almost exclusive vector of Trypanosoma cruzi in this country. The mean prevalence rate of T. cruzi human infection in urban and periurban sections of IV Region is 24.7%. To assess the impact of anti-T. infestans activities, by means of health education and sprayings of dwellings with insecticides, carried out in the IV Region since 1980, during January-February (summer) a serological follow-up to residents from 46 rural chagasic localities was performed. An indirect hemagglutination test and an indirect immunofluorescence test were done to each of the surveyed persons. In 1991, 303 (15.9%) out of 1,906 examined people resulted serologically positive. In 1992, previous discarding the positive individuals found in 1991, 1,334 persons were examined resulting positive 9 (0.7%). In 1993, 1,398 persons were surveyed and 26 (1.9%) were positive. It is noteworthy that none of these 35 positive persons had been surveyed in 1991, being difficult to assert if any was positive before. Two infants, daughters of positive mothers, serologically positive at the beginning, changed to negative in the following survey, indicating that it was a passive transfer of maternal specific antibodies. According to the results of this study, it is concluded that dwelling spraying with persistent-activity insecticides against T. infestans and health education are good tools in the control of T. cruzi human infection, particularly when the involved community participates.
Assuntos
Doença de Chagas/epidemiologia , População Rural , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Animais , Doença de Chagas/sangue , Doença de Chagas/prevenção & controle , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Seguimentos , Educação em Saúde , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição por Sexo , Trypanosoma cruzi/imunologiaRESUMO
In the period 1983-1994 a series of seroepidemiological surveys, by using immunodiagnostic tests for trichinosis, was carried out in 138 localities and health institutions from the 13 regions of the country. Thus, a total of 12,882 randomly selected persons, with different sex and age distribution, were submitted to precipitin test and indirect hemagglutination test for trichinosis. One hundred and ninety one (1.5%) persons resulted positive for trichinosis. Higher rates of infection were observed in central and southern Chile. No differences of positivity, according to age sex, but constant increase parallel to age of the individual were detected. The general prevalence rate of infection of 1.5% is in a reasonable accordance with the prevalence of 2.0% found in human corpses in 1992.