IntroductionIntestinal parasites are responsible for morbidity in children worldwide, especially in low income countries. In the present study we determine the prevalence of intestinal parasites and explore its association with anemia and stunting in school-aged children.MethodsA cross-sectional study was conducted from September to October 2010 enrolling 328 children attending the primary school in Lubango, the second largest city after the capital Luanda. Stool samples were collected for parasite detection through microscopy and molecular identification of Entamoeba histolytica and Entamoeba dispar. Stunting was assessed using the z-scores of height for age and hemoglobin concentration was determined using a portable hemoglobin analyzing system.ResultsThe global prevalence of pathogenic intestinal parasites was 44.2%, the most common being Ascaris lumbricoides (22.0%), Giardia lamblia (20.1%) and Hymenolepis nana (8.8%). Molecular detection revealed that 13.1% of the children carried E. dispar and 0.3% were infected with E. histolytica. The prevalence of stunting (mild to severe) was 41.5%. Stunting was more frequent in older children (p = 0.006, OR = 1.886), while anemia was more frequent in younger children (p = 0.005, OR = 2.210). The prevalence of anemia was 21.6%, and we found a significant association with infection by H. nana (p = 0.031, OR = 2.449).ConclusionsThis is one of the few published studies reporting intestinal parasites infection, nutritional status and anemia in children from Angola. Furthermore, the present work highlights the importance of regular intestinal parasites screening in children.

No abstract

Tsetse flies of the palpalis group are major vectors of Human African Trypanosomiasis in Africa. Accurate knowledge of species identity is essential for vector control. Here, we combine ribosomal internal transcribed spacer 1 (ITS1), mitochondrial Cytochrome Oxidase 1 (COI) and microsatellites to determine the population structure and phylogenetic relations of Glossina p. palpalis in Equatorial Guinea. CO1 sequence data suggest that G. p. palpalis in Equatorial Guinea is a distinct subspecies from previously described G. p. palpalis in West Africa and Democratic Republic of Congo. Glossina p. palpalis in Equatorial Guinea and DRC share a common ancestor which diverged from West African G. p. palpalis around 1.9 Ma. Previous ITS1 length polymorphism data suggested the possible presence of hybrids in Equatorial Guinea. However, ITS1 showed incomplete lineage sorting compared with clearly defined COI groups, and data from 12 unlinked microsatellites provided no evidence of hybridization. Microsatellite data indicated moderate but significant differentiation between the populations analysed (Rio Campo, Mbini and Kogo). Moreover, unlike previous studies of G. p. palpalis, there was no evidence for heterozygote deficiency, presence of migrants or cryptic population structure. Variance effective population size at Rio Campo was estimated at 501-731 assuming eight generations per year. This study of the population genetics of G. p. palpalis in central Africa provides the first estimate of genetic differentiation between geographically separated G. p. palpalis populations.

Introduction: Intestinal parasites are important contributors to the global disease burden, especially in children of low-income countries. The present study determined the frequency of intestinal parasites in children hospitalized at the diarrhea section of the Infectious-Contagious Diseases ward and at the Malnutrition ward of the Department of Pediatrics of the Maputo Central Hospital in Mozambique. Methodology: This pilot study conducted between February and March 2009 enrolled a total of 93 children between 1.5 and 48.2 months of age; 87.1% were younger than 24 months. Parasite detection in stool samples was achieved using direct microscopic observation and Ritchie's concentration technique. Results: Infection with pathogenic intestinal parasites was detected in 16.1% (15/93) of the children. Giardia duodenalis and Trichuris trichiura were the most common parasites (6.5%, 6/93 each), followed by Ascaris lumbricoides (2.2%, 2/93). One case of mixed infection with A. lumbricoides plus T. trichiura was also detected. Conclusion: This study reinforces the importance of routinely examining stool samples for the diagnosis of intestinal parasites (including protozoa) in children hospitalized in endemic areas.

The cumulative effect of repeated asymptomatic enteric infections on intestinal barrier is not fully understood in infants. We aimed to evaluate the association between previous enteric parasitic infections and intestinal inflammation and permeability at 24-months of age, in asymptomatic infants of São Tomé Island. A subset of infants from a birth cohort, with intestinal parasite evaluations in at least four points of assessment, was eligible. Intestinal inflammatory response and permeability were assessed using fecal S100A12 and alpha-1-antitrypsin (A1AT), respectively. The cutoff <-1SD for weight-for-length and length-for-age was used to define wasting and stunting. Multivariable linear regression analysis explored if cumulative enteric parasitic infections explained variability of fecal biomarkers, after adjusting for potential confounders. Eighty infants were included. Giardia duodenalis and soil-transmitted helminths (STH) were the most frequent parasites. The median (interquartile range) levels were 2.87 μg/g (2.41-3.92) for S100A12 and 165.1 μg/g (66.0-275.6) for A1AT. Weak evidence of association was found between S100A12 levels and G. duodenalis (p = 0.080) and STH infections (p = 0.089), and between A1AT levels and parasitic infection of any etiology (p = 0.089), at 24-months of age. Significant associations between A1AT levels and wasting (p = 0.006) and stunting (p = 0.044) were found. Previous parasitic infections were not associated with fecal biomarkers at 24 months of age. To summarize, previous asymptomatic parasitic infections showed no association with intestinal barrier dysfunction. Notwithstanding, a tendency toward increased levels of the inflammatory biomarker was observed for current G. duodenalis and STH infections, and increased levels of the permeability biomarker were significantly associated with stunting and wasting.