The relative contribution of immigration or local increase for persistence of urban schistosomiasis in Salvador, Bahia, Brazil.

Urbanization is increasing across the globe, and diseases once considered rural can now be found in urban areas due to the migration of populations from rural endemic areas, local transmission within the city, or a combination of factors. We investigated the epidemiologic characteristics of urban immigrants and natives living in a neighborhood of Salvador, Brazil where there is a focus of transmission of Schistosoma mansoni. In a cross-sectional study, all inhabitants from 3 sections of the community were interviewed and examined. In order to determine the degree of parasite differentiation between immigrants and the native born, S. mansoni eggs from stools were genotyped for 15 microsatellite markers. The area received migrants from all over the state, but most infected children had never been outside of the city, and infected snails were present at water contact sites. Other epidemiologic features suggested immigration contributed little to the presence of infection. The intensity and prevalence of infection were the same for immigrants and natives when adjusted for age, and length of immigrant residence in the community was positively associated with prevalence of infection. The population structure of the parasites also supported that the contribution from immigration was small, since the host-to-host differentiation was no greater in the urban parasite population than a rural population with little distant immigration, and there had been little differentiation in the urban population over the past 7 years. Public health efforts should focus on eliminating local transmission, and once eliminated, reintroduction from distant migration is unlikely.

The effect of autologous concentrated bone-marrow grafting on the healing of femoral shaft non-unions after locked intramedullary nailing.

The aim of this study was to assess the union rates in a series of patients with failed femoral shaft aseptic non-union who were treated with percutaneous concentrated autologous bone marrow grafting. Bone marrow harvesting and cell injection were performed under general anaesthesia in a single surgical procedure. Radiographic union was diagnosed in fractures with a score ≥ 10 according to the radiographic union scale in tibial fractures (RUST) and confirmed by clinical examination. Eight out of 16 patients progressed to consolidation (RUST score ≥ 10). Radiographic evidence of fracture union was observed at an average of 4.75 ± 1.75 months (range 3 to 8 months). All eight patients who did not progress to union within 12 months following the cell grafting procedure had a RUST score ≤ 10 (range 4 to 9). There were no differences in age, number of previous surgeries, duration of nonunion and preoperative RUST score between the patients that developed solid union and those with failed consolidation. However, a relationship between the number of osteoprogenitors injected and the rate of union was noted, 20.2 ± 8.6 × 10(8) versus 9.8 ± 4.3 × 10(8), p<0.005, between the patients with and without union, respectively. The efficacy of percutaneous autologous concentrated bone marrow grafting seems to be related to the number of osteoprogenitors available in the aspirates. Optimisation of the aspiration technique and concentration process is of paramount importance to increase the incidence of a successful outcome.

Genetic population structure of cercariae from an urban foci of Schistosoma mansoni, Brazil.

Rapid urbanization in Brazil has meant that many persons from rural areas where Schistosoma mansoni is endemic have migrated to cities. Discovery of a focus of active transmission in the city of Salvador prompted a citywide survey for active and potential transmission sites. Cercariae shed from infected snails collected from four locations were used to determine how these samples were related and if they were representative of the parasite population infecting humans. Each cercarial collection was greatly differentiated from the others, and diversity was significantly lower when compared with eggs from natural human infections in one site. Egg samples collected 7 years apart in one neighborhood showed little differentiation (Jost's D = 0.01-0.03). Given the clonal nature of parasite reproduction in the snail host and the short-term acquisition of parasites, cercariae from collections at one time point are unlikely to be representative of the diversity in the human population.

Analysis of Schistosoma mansoni population structure using total fecal egg sampling.

Many parasite populations are difficult to sample because they are not uniformly distributed between several host species and are often not easily collected from the living host, thereby limiting sample size and possibly distorting the representation of the population. For the parasite Schistosoma mansoni, we investigated the use of eggs, in aggregate, from the stools of infected individuals as a simple and representative sample. Previously, we demonstrated that microsatellite allele frequencies can be accurately estimated from pooled DNA of cloned S. mansoni adults. Here, we show that genotyping of parasite populations from reproductively isolated laboratory strains can be used to identify these specific populations based on characteristic patterns of allele frequencies, as observed by polyacrylamide gel electrophoresis and automated sequencer analysis of fluorescently labeled PCR products. Microsatellites used to genotype aggregates of eggs collected from stools of infected individuals produced results consistent with the geographic distribution of the samples. Preferential amplification of smaller alleles, and stutter PCR products, had negligible effect on measurement of genetic differentiation. Direct analysis of total stool eggs can be an important approach to questions of population genetics for this parasite by increasing the sample size to thousands per infected individual and by reducing bias.

[Urban transmission of schistosomiasis in children from a neighborhood of Salvador, Bahia]. / Transmissão urbana de esquistossomose em crianças de um bairro de Salvador, Bahia.

In the Subúrbio Ferroviário region of Salvador (Bahia, Brasil) occurrences of schistosomiasis were found. This fact motivated the investigation of the prevalence of the eggs in a group of 268 resident students in one of its neighborhoods (São Bartolomeu). The parasitological test analyzed by the Kato-Katz methodology, showed positive results in 30.2% of the children, ranging from 24 to 2,160 eggsSchistosoma mansoni/gram of feces. Infection was predominant in boys and in those 10 years old and over. Observation revealed that infection predominated in children that live close to natural water bodies. This region was where the three registered cases of hepatosplenicos occurred. Moreover, all the 81 children infected with Schistosoma mansoni eggs were born and live in the study area. Since this neighborhood presents all the elements of the epidemiological chain of Schistosoma mansoni, the evidences strongly suggests the urban transmission of this infection.

Síndrome metabólica na infância e adolescência: um fator maior de risco cardiovascular / Metabolic syndrome in children and adolescents: a major cardiovascular risk factor

A Síndrome Metabólica (SM), transtorno complexo representado por um conjunto de fatores de risco de doença cardiovascular aterosclerótica com elevada incidência e prevalência no adulto, tem início na infância e a sua evolução clínica no adulto é modulada por fatores hereditários e ambientais. O objetivo deste artigo é rever os principais aspectos etiopatogênicos, epidemiológicos, clínicos, terapêuticos e preventivos da síndrome metabólica, com enfoque na infância e adolescência. Os dados foram coletados no Medline, período de 1988 a 2005 - seleção de estudos anátomopatológicos, epidemiológicos, clínicos e de diretrizes, e permitiram a seguinte síntese: o conhecimento da síndrome metabólica na população pediátrica está em evolução; o sobrepeso/obesidade na infância e adolescência é o principal fator de risco predisponente para o desenvolvimento de doenças cardiovasculares na vida adulta, por facilitar o aparecimento de hiperinsulinemia, dislipidemia e hipertensão arterial; a identificação precoce e a implementação de medidas para o controle do sobrepeso/obesidade deve representar a principal forma de atuação do pediatra. Concluiu-se que a intervenção precoce sobre o estilo de vida de crianças e adolescentes é fundamental para prevenir complicações metabólicas e cardiovasculares na vida adulta.

Transmissão urbana de esquistossomose em crianças de um bairro de Salvador, Bahia / Urban transmission of schistosomiasis in children from a neighborhood of Salvador, Bahia

Na região do Subúrbio Ferroviário da cidade do Salvador (Bahia, Brasil), foram relatados casos de esquistossomose, e isso motivou este estudo de prevalência em 268 escolares residentes em um dos seus bairros (São Bartolomeu). Em 30,2 por cento das crianças, o exame parasitológico (Kato-Katz) foi positivo, com carga parasitária entre 24 a 2.160 ovos de Schistosoma mansoni/g de fezes, predominando entre os meninos e nos maiores de 10 anos de idade. Nas crianças com residências mais próximas das coleções naturais de água, ocorreu maior freqüência de eliminadores de ovos e nela residiam os três únicos casos com a forma hepatosplênica da esquistossomose. Também, todas as 81 crianças com ovos de Schistosoma mansoninas fezes nasceram e sempre residiram na área de estudo. Como nesse bairro há todos os elementos da cadeia epidemiológica do Schistosoma mansoni, são fortes as evidências da transmissão urbana dessa infecção.

In the Subúrbio Ferroviário region of Salvador (Bahia, Brasil) occurrences of schistosomiasis were found. This fact motivated the investigation of the prevalence of the eggs in a group of 268 resident students in one of its neighborhoods (São Bartolomeu). The parasitological test analyzed by the Kato-Katz methodology, showed positive results in 30.2 percent of the children, ranging from 24 to 2,160 eggsSchistosoma mansoni/gram of feces. Infection was predominant in boys and in those 10 years old and over. Observation revealed that infection predominated in children that live close to natural water bodies. This region was where the three registered cases of hepatosplenicos occurred. Moreover, all the 81 children infected with Schistosoma mansoni eggs were born and live in the study area. Since this neighborhood presents all the elements of the epidemiological chain of Schistosoma mansoni, the evidences strongly suggests the urban transmission of this infection.

Prevalence of cardiovascular risk factors in selected samples of schoolchildren--socioeconomic influence.

Few data are available regarding the prevalence of cardiovascular risk factors in schoolchildren in Brazil. Weight, height, body mass index, blood pressure, and serum cholesterol were determined in 366 students, from 6-12 years of age, 209 (57.1%) from a private school and 157 (41.9%) from a public school, 187 (51.1%) female, aged 8.4+/-1.7 years. Prevalence of the risk of being overweight was 14.8%, being overweight/obese 13.1%, and presenting with elevated cholesterol (>/=170 mg/dL) was 28.1%, particularly at the private school: 21.5% vs. 5.7% for the risk of being overweight (p<0.001), 17.2% vs. 7.6% for being overweight/obese (p<0.01), 41.8% vs. 10.2% for cholesterol >/=170 mg/dL (p<0.001), and 14.8% vs. 1.3% for cholesterol >/=200 mg/dL (p<0.001), respectively. The results showed a high prevalence of risk factors among these school children, especially among private students.