Intestinal parasitism and nutritional status among indigenous children from the Argentinian Atlantic Forest: Determinants of enteroparasites infections in minority populations.

OBJECTIVE: Intestinal parasitoses, especially in the less favored populations of tropical and subtropical areas, are a scourge of high impact in public health. We conducted a cross-sectional survey to investigate the prevalence of helminths and protozoa pathogens, malnutrition, and their determinants in children from indigenous Mbyá Guaraní villages of Iguazú, in the subtropical Atlantic Forest of Argentina. METHODS: Parasitological assessment was performed using a combination of flotation, sedimentation, and centrifugation techniques, as well as temporal and permanent stains. Nutritional assessment was based on nutritional indicators derived from anthropometric measurements. Statistical analysis of socio-demographic determinants was assessed by Generalized Linear Mixed Models at individual, household, and village levels. RESULTS: A total of 303 children from 140 families from Fortin Mbororé and Yriapú Jungle villages participated, and 87.8% of them resulted positive to at least one parasite. Multiparasitism reached 70% and children with up to six different parasites were detected. Thirteen genera were identified, of which eight were pathogenic. The most frequent soil-transmitted helminths were hookworms and Strongyloides stercoralis with 60.7 and 41.9%, respectively. Enterobius vermicularis was detected in 28.4% of children. Giardia duodenalis was the main protozoan and reached the 33.3%. The prevalence of stunting and underweight were 38.9% and 6.9%, whereas for overweight and obesity were 28.1% and 12.9%, respectively. An association was observed between stunting in older children and the presence of parasites, multiparasitism, and giardiasis. Individual conditions and habits were important determinants for most of the parasitoses. CONCLUSIONS: We evidenced that the community is affected by the double burden of malnutrition and parasitoses. To face this alarming situation, public policies are needed to improve sanitation, hygiene education access, community deworming programs, and quality nutrition on a regular basis of intercultural approaches.

Prevention of intestinal parasites in a tri-border area of Latin America: Children perceptions and an integral health education strategy.

To investigate knowledge of school-aged children and their perception on intestinal parasites, and to assess knowledge reconstruction on prevention practices after specific training in the subject. We performed an activity package that included the analysis of children's drawings of intestinal parasites, and information and communication technologies (ITCs) to transfer knowledge about these pathogens and prevention measures. Retrieval learning activities were performed to fixation of general and specific prevention and control measures.Overall, we found that there is a knowledge gap in many aspects of parasite biology and ecology, and therefore on the risk of infection and acquisition mechanisms. After ITCs, the children improved their knowledge over non-trained children.The approaches used to transfer knowledge and for learning, fixation were valuable tools for incorporating changes in misconceptions and in the deep-rooted habits that favour entero-parasitic diseases. This has important implications for the specific design of future education materials and campaigns. Understanding of perceptions helps to provide justifications and knowledge to achieve changes in unhealthy habits, and it constitutes the basis for the transformation of many risky practices.

The effect of habitat fragmentation on the genetic structure of a top predator: loss of diversity and high differentiation among remnant populations of Atlantic Forest jaguars (Panthera onca).

Habitat fragmentation may disrupt original patterns of gene flow and lead to drift-induced differentiation among local population units. Top predators such as the jaguar may be particularly susceptible to this effect, given their low population densities, leading to small effective sizes in local fragments. On the other hand, the jaguar's high dispersal capabilities and relatively long generation time might counteract this process, slowing the effect of drift on local populations over the time frame of decades or centuries. In this study, we have addressed this issue by investigating the genetic structure of jaguars in a recently fragmented Atlantic Forest region, aiming to test whether loss of diversity and differentiation among local populations are detectable, and whether they can be attributed to the recent effect of drift. We used 13 microsatellite loci to characterize the genetic diversity present in four remnant populations, and observed marked differentiation among them, with evidence of recent allelic loss in local areas. Although some migrant and admixed individuals were identified, our results indicate that recent large-scale habitat removal and fragmentation among these areas has been sufficiently strong to promote differentiation induced by drift and loss of alleles at each site. Low estimated effective sizes supported the inference that genetic drift could have caused this effect within a short time frame. These results indicate that jaguars' ability to effectively disperse across the human-dominated landscapes that separate the fragments is currently very limited, and that each fragment contains a small, isolated population that is already suffering from the effects of genetic drift.