Economic activity and congenital anomalies: an ecologic study in Argentina. ECLAMC ECOTERAT Group.
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In this study, we analyze the association between industrial activity and the occurrence of 34 congenital anomalies. We selected 21 counties in Argentina during 1982-1994 and examined a total of 614,796 births in these counties in consecutive series. We used the International Standard Industrial Classification of All Economic Activities (United Nations, 1968) as an indicator of exposure to 80 specific industrial activities. Incidence rate ratios for each congenital anomaly were adjusted by the socioeconomic level of the county according to a census index of social deprivation. For a given exposure/anomaly association to be considered as significant and relevant, the exposure had to be a statistically significant risk for the occurrence of the anomaly and an increase in the birth prevalence rate of the congenital anomaly type involved had to be observed in those counties where the putative causal activity was being performed. Significant associations (p < 0.01) were identified between textile industry and anencephaly, and between the manufacture of engines and turbines and microcephaly. These observations are consistent with previous reports on occupational exposure, and their further investigation by means of case-control studies is recommended. (+info)
Perinatal factors associated with blood pressure during childhood.
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This study aims to determine whether variables reflecting an adverse intrauterine environment are associated with childhood blood pressure. The authors conducted a secondary analysis of data from a prospective cohort of children born to healthy, nulliparous women enrolled in a randomized controlled trial. A total of 518 children were traced in 1995-1996 from 614 eligible children born in a clinic in Rosario, Argentina. The outcome was systolic blood pressure at 5-9 years. Hemoglobin during pregnancy was positively associated with children's pressure. Other maternal characteristics during pregnancy (blood pressure, smoking, weight gain, weight at 20 weeks' gestation, and glycemia) and size at birth (birth weight, ponderal index, head circumference/length ratio, and small for gestational age) were not associated with children's pressure. Among children in the upper quartile of body mass index, there was a weak inverse correlation between birth weight and systolic pressure, and systolic pressure was 14.8 mmHg (95 percent confidence interval: 3.3, 26.4) higher in low birth weight children than in others. The main predictors of childhood pressure were childhood body mass index and maternal pressure outside pregnancy. In this healthy population, the authors found weak support for an association between variables reflecting an adverse fetal environment and childhood blood pressure. Low birth weight was a risk factor for high blood pressure only in overweight children. (+info)
New species records for the blackfly (Diptera-simuliidae) fauna of Argentina with description of adults, pupa and larva of Simulium oyapockense s. l. And S. seriatum.
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Two blackfly species Simulium (Cerqueirellum) oyapockense Floch & Abonnenc and S. (Hemicnetha) seriatum Knab are recorded from Argentina, representing the most southern register for both species. S. oyapockense is a species epidemiologically very important, as a vector of onchocerciasis in the Amazonian focus. Both species are described and illustrated and their distribution are reported, in similarity to others like S. roraimense Nunes de Mello and S. ganalesense Vargas et al. in reference to S. oyapockense and S. mexicanum Bellardi similar to S. seriatum are discussed. (+info)
Asymptomatic infections by diarrheagenic Escherichia coli in children from Misiones, Argentina, during the first twenty months of their lives.
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Diarrheagenics Escherichia coli are the major agents involved in diarrheal disease in developing countries. The aim of this study was to evaluate the time of appearance of the first asymptomatic infection by the different categories of diarrheagenic E. coli in 44 children since their birth and during the first 20 months of their lives. In all of the children studied, we detected at least one category of diarrheagenic E. coli through the 20 months of the study. 510 diarrheagenic E. coli (33.5%) were obtained from the 1,524 samples collected from the 44 children during the time of the study (31.4% EAggEC, 28.8% EPEC, 27.1% DAEC, and 12.7% ETEC). Neither EHEC nor EIEC were identified. The median age for diarrheagenic E. coli colonization was 7.5 months. The mean weaning period was 12.8 months and the mean age for introduction of mixed feeding (breast fed supplemented) was 3.8 months. A significantly lower incidence of diarrheal disease and asymptomatic infections was recorded among the exclusively breast-fed rather than in the supplemented and non breast-fed infants. For ETEC, EPEC and EAggEC the introduction of weaning foods and complete termination of breast-feeding were associated with an increase of asymptomatic infections. (+info)
Incidence and nature of the most common rugby injuries sustained in Argentina (1991-1997).
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OBJECTIVE: To study the incidence of the most commonly sustained injuries in Argentine rugby and analyse them according to type, position and age of the players, and phase and time of play. METHODS: A prospective registry of injuries was constructed in different provincial unions of Argentina. Data were collected during a whole weekend each year from 1991 to 1997. Chi2 with Yates correction test, contingency tables, odds ratios (OR), and 95% confidence intervals (CI) were calculated (Epi Info Version 6.04a). RESULTS: A total of 924 injuries were registered in 1296 rugby games, involving 38 933 players. The mean (SD) incidence per weekend was 2.4 (0.2)% (95% CI 2.22 to 2.53), and the number of injuries per season was 24,188. Overall, senior players suffered more injuries than those in younger divisions (OR = 1.53; 95% CI 1.34 to 1.76; p<0.0001). The most common type of injury was pulled muscles of the lower limbs (11.7%, p<0.0001). Overall, the knee was the most susceptible to injury (14.1%, p<0.0001). Senior players suffered more pulled muscles of the lower limbs (OR = 2.99; 95% CI 2.01 to 4.46; p<0.0001), ankle ligament distension (OR = 1.69; 95% CI 1.12 to 2.53; p = 0.01), knee trauma (OR = 1.69; 95% CI 1.06 to 2.68; p = 0.02), bleeding wounds on the face (OR = 3.86; 95% CI 2.24 to 6.70; p<0.0001), and knee ligament distension (OR = 2.14; 95% CI 1.16 to 3.96; p = 0.01). Younger players had a greater risk of suffering muscular or ligament injuries of the cervical column (OR = 3.0; 95% CI 1.05 to 10.08; p = 0.04). The forwards had a higher risk of injury (OR = 1.41; 95% CI 1.23 to 1.61; p<0.0001). The most commonly injured player was the flanker (15.5%, p<0.01), and the most common mechanism was in open play (33%). More injuries were sustained in the second half (OR = 1.17; 95% CI 1.03 to 1.34; p = 0.01). CONCLUSIONS: Injuries are the cause of significant morbidity among rugby players in Argentina. A more thorough investigation and a greater understanding of the mechanisms are crucial in order to update the rugby laws and reduce this high injury incidence. (+info)
Human toxocarosis. Its seroprevalence in the city of La Plata.
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Toxocara canis is very common in dogs throughout the world. It is the primary cause of visceral larva migrans (VLM) in humans. Soil contaminated with T. canis embryonated eggs is the main source of infection of man. Our objective was to describe Toxocara seroprevalence in humans in the city of La Plata associated with some determinants such asage, presence or absence of clinical manifestations and risk factors. Blood samples were collected at random from 156 patients of different sex and age, with and without clinical symptoms compatible with the disease. The diagnostic technique ELISA test was performed with the Bordier Affinity Products Commercial Kit, using excretory-secretory Toxocara antigen with a sensitivity higher than 90%. The values were positive in 39% of the studied population. In the analysis according to age, the younger group presented significant differences with respect to the older one (Chi-square p<0.05). Positive patients presented clinical symptoms compatible with the disease (84%), and 41% presented some risk factor. The level of positivity obtained indicates a certain risk of being infects mainly in patients younger than 15 years old. The authors agree that an early identification and treatment of VLM may save a life. (+info)
Congenital transmission of Trypanosoma cruzi: an operational outline for detecting and treating infected infants in north-western Argentina.
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We designed a set of procedures for first-line local health services to detect and treat the congenital transmission of Trypanosoma cruzi at a province-wide scale, and field-tested the programme in the province of Tucuman, northwestern Argentina, from 1992 to 1994. The programme consists of routine screening of pregnant women for seroreactivity to T. cruzi, serological and parasitological follow-up of the newborn at least twice during the first year of age, treatment of the infected infants, and evaluation of the outcome. 927 (5.5%) of 16 842 pregnant women were seroreactive to T. cruzi by indirect haemagglutination assay and ELISA. Twenty-one (6.7%) of 315 newborns to seroreactive mothers were diagnosed as infected with T. cruzi parasites microhaematocrit concentration before 30 days of age. Five newborns who initially tested negative had a T. cruzi infection detected by microhaematocrit and/or serological techniques at 3 or 6 months of age. Thus, congenital infection was diagnosed in 26 (7.1%) infants born to seroreactive women and residing in houses free of triatomine bugs. Four of 6 infants born to seroreactive mothers died during the first year of age and had some evidence of T. cruzi infection; one of the deaths was attributed to T. cruzi based on clinical evidence. After specific treatment with nifurtimox or benznidazole, 30 of 32 infants remained parasitologically and serologically negative. This study shows the feasibility of controlling the incidence of congenitally acquired T. cruzi infections at a province-wide scale by means of a specific screening programme at first-line health services level. (+info)
Reduced genetic variation and the success of an invasive species.
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Despite the severe ecological and economic damage caused by introduced species, factors that allow invaders to become successful often remain elusive. Of invasive taxa, ants are among the most widespread and harmful. Highly invasive ants are often unicolonial, forming supercolonies in which workers and queens mix freely among physically separate nests. By reducing costs associated with territoriality, unicolonial species can attain high worker densities, allowing them to achieve interspecific dominance. Here we examine the behavior and population genetics of the invasive Argentine ant (Linepithema humile) in its native and introduced ranges, and we provide a mechanism to explain its success as an invader. Using microsatellite markers, we show that a population bottleneck has reduced the genetic diversity of introduced populations. This loss is associated with reduced intraspecific aggression among spatially separate nests, and leads to the formation of interspecifically dominant supercolonies. In contrast, native populations are more genetically variable and exhibit pronounced intraspecific aggression. Although reductions in genetic diversity are generally considered detrimental, these findings provide an example of how a genetic bottleneck can lead to widespread ecological success. In addition, these results provide insights into the origin and evolution of unicoloniality, which is often considered a challenge to kin selection theory. (+info)