High prevalence of intestinal parasite infestations among stunted and control children aged 2 to 5 years old in two neighborhoods of Antananarivo, Madagascar

Author summary In populations living in adverse conditions due to poverty, a wide variety of intestinal parasite infestations can be observed. These infestations are usually diagnosed by stool microscopy but can be easily overlooked if the procedures used are inaccurate or performed in a suboptimal way. In the present study, we investigated the prevalence of intestinal parasite infestations in stunted and control children aged from 2 to 5 years living in two disadvantaged neighborhoods of Antananarivo Madagascar. We also assessed risk factors for infestations and the diagnostic performance of microscopic techniques and real-time PCR for the detection of parasites. Almost all individuals were found to be infested with at least one parasitic species. Children aged between 4 and 5 years and mothers with low educational levels were found to be associated with infestation. Similarly, children drinking untreated water were associated with G. intestinalis and E. histolytica infestation. This latter species was also associated with moderately stunted children. Children between 4 and 5 years old and with no cemented soil type were associated with T. trichiura infestation. The high prevalence of intestinal parasite infestations among the study participants requires the improvement of health education, environmental sanitation and quality of water sources. Background This study aimed to compare the prevalence of intestinal parasite infestations (IPIs) in stunted children, compared to control children, in Ankasina and Andranomanalina Isotry (two disadvantaged neighborhoods of Antananarivo, Madagascar), to characterize associated risk factors and to compare IPI detection by real-time PCR and standard microscopy techniques. Methodology/Principal findings Fecal samples were collected from a total of 410 children (171 stunted and 239 control) aged 2-5 years. A single stool sample per subject was examined by simple merthiolate-iodine-formaldehyde (MIF), Kato-Katz smear and real-time PCR techniques. A total of 96.3% of the children were infested with at least one intestinal parasite. The most prevalent parasites were Giardia intestinalis (79.5%), Ascaris lumbricoides (68.3%) and Trichuris trichiura (68.0%). For all parasites studied, real-time PCR showed higher detection rates compared to microscopy (G. intestinalis [77.6% (n = 318) versus 20.9% (n = 86)], Entamoeba histolytica [15.8% (n = 65) versus 1.9% (n = 8)] and A. lumbricoides [64.1% (n = 263) versus 50.7% (n = 208)]). Among the different variables assessed in the study, age of 4 to 5 years (AOR = 4.61; 95% CI, (1.35-15.77)) and primary and secondary educational level of the mother (AOR = 12.59; 95% CI, (2.76-57.47); AOR = 9.17; 95% CI, (2.12-39.71), respectively) were significantly associated with IPIs. Children drinking untreated water was associated with infestation with G. intestinalis (AOR = 1.85; 95% CI, (1.1-3.09)) and E. histolytica (AOR = 1.9; 95% CI, (1.07-3.38)). E. histolytica was also associated with moderately stunted children (AOR = 0.37; 95% CI, 0.2-0.71). Similarly, children aged between 4 and 5 years (AOR = 3.2; 95% CI (2.04-5.01)) and living on noncemented soil types (AOR = 1.85; 95% CI, (1.18-2.09)) were associated with T. trichiura infestation. Conclusions/Significance The prevalence of IPIs is substantial in the studied areas in both stunted and control children, despite the large-scale drug administration of antiparasitic drugs in the country. This high prevalence of IPIs warrants further investigation. Improved health education, environmental sanitation and quality of water sources should be provided.

Automated summary

The study found a high prevalence of intestinal parasite infestations among children living in disadvantaged areas in Madagascar, with almost all individuals infected with at least one parasitic species. Children aged 4 to 5 and mothers with low educational levels were associated with infestation, while children drinking untreated water were linked to certain parasite infestations. Stunted children were also associated with certain parasite infections.