Children from a rural region in The Chiapas Highlands, Mexico, show an increased risk of stunting and intestinal parasitoses when compared with urban children.

Background: The state of Chiapas has held the first place of extreme poverty in Mexico. The majority of Chiapas' municipalities are inhabited by marginalized, indigenous populations, who usually present diarrhea of unknown etiology. We evaluated the nutritional status, intestinal parasites, and common bacterial pathogens, including DEC (diarrheagenic Escherichia coli) strains, in 178 children under five years of age with a high (rural) and a moderate (urban) degree of marginalization. Methods: Z-scores for anthropometric indexes from the children were obtained, whereas intestinal parasites were investigated by using a direct coproparasitoscopic analysis and a concentration method. DEC strains were detected by polymerase chain reaction (PCR). Results: The stunting prevalence in children from the rural and urban regions was 79.8 and 7.5%, respectively. Only children from rural municipalities were parasitized (72.6%), being Ascaris lumbricoides and Entamoeba histolytica/Entamoeba dispar the most prevalent parasites (57.1 and 38.1%, respectively). More than half of the children presented moderated ascariasis. Besides Giardia intestinalis, these parasites were associated with stunting. The prevalence of DEC strains was similar in both regions. Conclusions: Only children from the Chiapas Highlands (rural zone) exhibited high prevalences of stunting and intestinal parasites. A reevaluation of social development programs should be in place to address stunting and intestinal parasitoses, mainly in rural regions of Chiapas, to avoid adverse functional consequences on these children.

Introducción: El estado de Chiapas ha ostentado el primer lugar de pobreza extrema en México. La mayor parte de la población de los municipios de Chiapas es indígena, vive en condiciones de marginación y padece de diarrea de etiología desconocida. Este trabajo evaluó el estado nutricional, la presencia de parásitos intestinales y patógenos bacterianos comunes, además de cepas DEC (Escherichia coli diarreogénica) en 178 niños menores de cinco años, provenientes de una localidad con alto grado de marginación (rural) y de una con moderada marginación (urbana). Métodos: Se obtuvieron los puntajes Z de los índices antropométricos de los niños. Los parásitos intestinales se investigaron con el método coproparasitoscópico directo y un método de concentración. Las cepas DEC se detectaron mediante reacción en cadena de la polimerasa. Resultados: La prevalencia de desmedro en niños de la zona rural y urbana fue de 79.8 y 7.5%, respectivamente. Únicamente los niños de la zona rural estuvieron parasitados (72.6%), y los más prevalentes fueron Ascaris lumbricoides y Entamoeba histolytica/Entamoeba dispar (57.1 y 38.1%, respectivamente). Más de la mitad de los infantes exhibieron ascariasis moderada. Estos parásitos, además de Giardia intestinalis, se asociaron con el desmedro. En ambas regiones, la prevalencia de DEC fue similar. Conclusiones: Solo los niños de los Altos de Chiapas (zona rural) exhibieron alta prevalencia de desmedro y parásitos intestinales. Para evitar las consecuencias adversas entre los infantes, es necesario reevaluar los programas de desarrollo social para combatir el desmedro y la parasitosis intestinal, principalmente en las regiones rurales de Chiapas.

Malnutrition and the presence of intestinal parasites in children from the poorest municipalities of Mexico.

BACKGROUND: For many years Chiapas, Mexico's poorest state, has had the highest rate of child mortality due to intestinal infections of unknown etiology in the country. To begin identifying the infectious agents, our work determined the prevalence of intestinal parasites as well as malnutrition in children from Chiapas's three most impoverished municipalities: Pantepec, Chanal, and Larrainzar. METHODOLOGY: In this cross-sectional study, conducted between January and November 2009, we assessed the prevalence of intestinal parasites by means of coproparasitological analysis in children <5 years of age (N=250) from three of the marginalized municipalities: Pantepec, Chanal and Larrainzar. The prevalence of malnutrition was then assessed using the Mexican official norm NOM-031-SSA2-1999 and WHO criteria. We evaluated the association between age (breast-fed and pre-school children) with parasites and nutritional status. RESULTS: Our analysis revealed the highest prevalence of intestinal parasites in children from Pantepec (62.8%), followed by Chanal (47.3%), and then Larrainzar (11.9 %). The nematode Ascaris lumbricoides was the most prevalent enteroparasite (33.6%). Anthropometric analysis revealed that >40% of children represented varying degrees of malnutrition and a marked constitutional delay in growth. A very high prevalence of stunting was also recorded in children from Chanal and Larrainzar (70% and 55%, respectively). An association between infection with intestinal parasites and malnutrition was observed in Pantepec. Preschool-age children were more likely to be infected with intestinal parasites. CONCLUSION: Our results indicate the urgent need for interventions in order to 1) improve the nutritional status of children and 2) reduce infection rates of enteric parasites.