Functional Significance of Low-Intensity Polyparasite Helminth Infections in Anemia

• Published in: The Journal of infectious diseases Vol. 192; no. 12; pp. 2160 - 2170
• Main Authors: Ezeamama, Amara E., Friedman, Jennifer F., Olveda, Remigio M., Acosta, Luz P., Kurtis, Jonathan D., Mor, Vincent, McGarvey, Stephen T.
• Format: Journal Article
• Language: English
• Published: Chicago, IL The University of Chicago Press 15.12.2005; University of Chicago Press; Oxford University Press
• Subjects: Adolescent; Anemia; Anemia - complications; Anemia - epidemiology; Animals; Ascariasis - complications; Ascariasis - epidemiology; Ascariasis - parasitology; Biological and medical sciences; Child; Child nutrition; Cross-Sectional Studies; Feces - parasitology; Female; Fundamental and applied biological sciences. Psychology; Hemoglobins; Humans; Infections; Infectious diseases; Logistic Models; Male; Medical sciences; Microbiology; Morbidity; Necatoriasis - complications; Necatoriasis - epidemiology; Necatoriasis - parasitology; Nematoda - classification; Nematoda - isolation & purification; Nematode Infections - complications; Nematode Infections - epidemiology; Nematode Infections - parasitology; Nutritional status; Parasite Egg Count; Parasites; Philippines - epidemiology; Schistosoma japonicum - classification; Schistosoma japonicum - isolation & purification; Schistosomiasis japonica - complications; Schistosomiasis japonica - epidemiology; Schistosomiasis japonica - parasitology; Socioeconomic status; Trichuriasis - complications; Trichuriasis - epidemiology; Trichuriasis - parasitology; Underweight; Z score; Philippines; Infection; Hemopathy; Parasitosis; Microbiology; Anemia; Helminthiasis
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/498219

Background.We wanted to quantify the impact that polyparasite infections, including multiple concurrent low-intensity infections, have on anemia Methods.Three stool samples were collected and read in duplicate by the Kato-Katz method in a cross-sectional sample of 507 children from Leyte, The Philippines. The number of eggs per gram of stool was used to define 3 infection intensity categories—uninfected, low, and moderate/high (M+)—for 3 geohelminth species and Schistosomiasis japonicum. Four polyparasite infection profiles were defined in addition to a reference profile that consisted of either no infections or low-intensity infection with only 1 parasite. Logistic regression models were used to quantify the effect that polyparasitism has on anemia (hemoglobin level <11 g/dL) Results.The odds of having anemia in children with low-intensity polyparasite infections were nearly 5-fold higher (P=.052) than those in children with the reference profile. The odds of having anemia in children infected with 3 or 4 parasite species at M+ intensity were 8-fold greater than those in children with the reference profile (P<.001) Conclusion.Low-intensity polyparasite infections were associated with increased odds of having anemia. In most parts of the developing world, concurrent infection with multiple parasite species is more common than single-species infections. This study suggests that concurrent low-intensity infections with multiple parasite species result in clinically significant morbidity