Ambient soil cation exchange capacity inversely associates with infectious and parasitic disease risk in regional Australia.
Sci Total Environ
; 626: 117-125, 2018 Jun 01.
Article
em En
| MEDLINE
| ID: mdl-29335166
ABSTRACT
Human contact with soil may be important for building and maintaining normal healthy immune defence mechanisms, however this idea remains untested at the population-level. In this continent-wide, cross-sectional study we examine the possible public health benefit of ambient exposures to soil of high cation exchange capacity (CEC), a surrogate for potential immunomodulatory soil microbial diversity. We compare distributions of normalized mean 2011/12-2012/13 age-standardized public hospital admission rates (cumulative incidence) for infectious and parasitic diseases across regional Australia (representing an average of 29,516â¯patients/year in 228 local government areas), within tertiles of socioeconomic status and soil exposure. To test the significance of soil CEC, we use probabilistic individual-level environmental exposure data (with or without soil), and group-level variables, in robust non-parametric multilevel modelling to predict disease rates in unseen groups. Our results show that in socioeconomically-deprived areas with high CEC soils, rates of infectious and parasitic disease are significantly lower than areas with low CEC soils. Also, health inequality (relative risk) due to socioeconomic status is significantly lower in areas with high CEC soils compared to low CEC soils (Δ relative riskâ¯=â¯0.47; 95% CI 0.13, 0.82). Including soil exposure when modelling rates of infectious and parasitic disease significantly improves prediction performance, explaining an additional 7.5% (Δ r2â¯=â¯0.075; 95% CI 0.05, 0.10) of variation in disease risk, in local government areas that were not used for model building. Our findings suggest that exposure to high CEC soils (typically high soil biodiversity) associates with reduced risk of infectious and parasitic diseases, particularly in lower socioeconomic areas.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Doenças Parasitárias
/
Solo
Tipo de estudo:
Etiology_studies
/
Observational_studies
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Prevalence_studies
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Prognostic_studies
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Risk_factors_studies
Aspecto:
Equity_inequality
/
Patient_preference
Limite:
Humans
País/Região como assunto:
Oceania
Idioma:
En
Revista:
Sci Total Environ
Ano de publicação:
2018
Tipo de documento:
Article