Global associations between the use of basic drinking water and sanitation services with diarrhoeal disease incidence in 200 countries and territories from 2000 to 2019

Objectives

Globally, billions of people do not have access to safely managed drinking water and sanitation services. Interventions to improve drinking water, sanitation and hygiene could reduce the incidence of diarrhoea in low- and middle-income countries. This study aimed to investigate the association between these services and the incidence of diarrhoea.

Study design

Worldwide, ecological observational study, utilising cross-sectional data.

Methods

Data from the Global Burden of Disease Study 2019 and World Bank were used in this study. Diarrhoeal disease episodes were defined as three or more loose bowel movements within 24 h. Estimated Annual Percentage Change was used to quantify trends in disease incidence over a specific time interval. Quasi-Poisson Generalised Linear Model was introduced to analyse the influence of basic drinking water and sanitation services on the incidence of diarrhoea. Subgroup analyses were carried out to determine potential variations in the incidence of diarrhoeal diseases according to sex, age and sociodemographic index (SDI) region.

Results

Between 2000 and 2019, the incidence rate of global diarrhoea remained consistent, with regional variations linked to SDIs. A 1% increase in access to basic drinking water was associated with a 0.41% (95% confidence interval [CI], 0.33%–0.50%) increase in the age-standardised incidence rate of diarrhoea; meanwhile, a 1% increase in sanitation service usage was associated with a 0.47% (95% CI, 0.40%–0.54%) reduction in the age-standardised incidence rate of diarrhoea. The correlation differed across SDI regions. The use of safely managed drinking water was associated with a reduction in diarrhoeal disease rates, but the effect was non-significant in High SDI regions. Higher diarrhoeal disease incidence was seen in younger and older populations. Individuals in the age groups 55–59 years and 10–14 years showed the greatest association of water service usage with diarrhoea, while an increase in sanitation service usage was related to decreased diarrhoea rates in most age groups, excluding children aged 5–14 years.

Conclusions

Emphasising initiatives to enhance water quality, elevate the standards of drinking water safety management, and strengthening related infrastructure development in global health policies and development plans could have a positive impact on overall global health. Such comprehensive interventions have the potential to not only prevent waterborne diseases but also elevate the general health status of societies worldwide.