Ascaris lumbricoides Infection Is Associated with Increased Risk of Childhood Asthma and Atopy in Rural China

• Published in: American journal of respiratory and critical care medicine Vol. 165; no. 11; pp. 1489 - 1493
• Main Authors: Palmer, Lyle J, Celedon, Juan C, Weiss, Scott T, Wang, Binyan, Fang, Zhian, Xu, Xiping
• Format: Journal Article
• Language: English
• Published: New York, NY Am Thoracic Soc 01.06.2002; American Lung Association
• Subjects: Adolescent; Age Distribution; Animals; Ascariasis; Ascariasis - diagnosis; Ascariasis - epidemiology; Ascaris lumbricoides - isolation & purification; Asthma - diagnosis; Asthma - epidemiology; Biological and medical sciences; Child; China - epidemiology; Cohort Studies; Comorbidity; Developing Countries; Diseases caused by nematodes; Helminthic diseases; Humans; Hypersensitivity, Immediate - diagnosis; Hypersensitivity, Immediate - epidemiology; Incidence; Infectious diseases; Medical sciences; Parasitic diseases; Risk Factors; Rural Population; Sampling Studies; Sex Distribution; Tropical medicine; Asia; China; Human; Allergy; Immunopathology; Ascaris lumbricoides; Respiratory disease; Parasitosis; Helminthiasis; Epidemiology; Asthma; Atopy; Infection; Ascariasis; Concomitant disease; Nematode disease; Risk factor; Helmintha; Nemathelminthia; Obstructive pulmonary disease; Invertebrata; Nematoda; Child; Public health
• ISSN: 1073-449X; 1535-4970
• DOI: 10.1164/rccm.2107020

There is growing international interest in the possible relationships between helminthic infection and allergic disease, although the nature of the relationships remains uncertain and controversial. The interrelationships of current and past infection with Ascaris lumbricoides and asthma and atopy were investigated in a cross-sectional sample of 2,164 children between the ages of 8 and 18 years from Anqing Province, China. The children were sampled from a larger family-based study of the genetics of asthma. The prevalence of either a history of or a positive stool examination for Ascaris was 24.5%. Asthma was defined for analytic purposes using previously validated, stringent criteria including airways responsiveness to methacholine. Independently of the other factors assessed, infection with A. lumbricoides was associated with increased risk of asthma (p < 0.001), an increased number of skin tests positive to aeroallergens (p < 0.001), and an increased dose-response slope to methacholine (p = 0.003). The association of sensitization to common aeroallergens with increased asthma risk was enhanced in those children infected with Ascaris, and such infection was associated with an increased risk of asthma independent of sensitization to aeroallergens in this selected population. These data suggest a complex relationship between ascariasis and susceptibility to childhood asthma among predisposed children that may involve an interaction with the immune response to inhaled aeroallergens.