Mobility in Blue-Green Spaces Does Not Predict COVID-19 Transmission: A Global Analysis

Area of Science:

• Environmental Science
• Epidemiology
• Public Health

Background:

• COVID-19 pandemic necessitated mobility restrictions, impacting public health and outdoor recreation.
• Blue-green spaces are crucial for physical and mental well-being.
• The impact of mobility restrictions in these spaces on disease transmission remains unclear.

Purpose of the Study:

• To assess if restrictions on human movement, specifically in blue-green spaces, influenced COVID-19 transmission.
• To identify key predictors of COVID-19 growth rates, including environmental factors and mobility patterns.

Main Methods:

• Utilized a spatially resolved dataset of COVID-19 cases from 848 administrative units in 153 countries (Feb 2020-Feb 2021).
• Measured blue-green space mobility using anonymized mobile phone tracking data.
• Employed machine learning forecast and linear mixed-effects models to analyze predictors of COVID-19 growth rates, controlling for environmental factors.

Main Results:

• No evidence found that increased visits to blue-green spaces correlated with higher COVID-19 transmission.
• Increased total mobility and the relaxation of non-pharmaceutical interventions (e.g., containment policies) predicted greater transmission.
• Ultraviolet radiation emerged as the most significant environmental factor reducing COVID-19 spread; temperature, humidity, wind speed, and air pollution had minimal effects.

Conclusions:

• Findings suggest limited evidence to support public health policies restricting outdoor mobility in blue-green spaces.
• Low risk of outdoor COVID-19 transmission is supported, aligning with experimental studies.
• Acknowledges challenges in big data approaches and suggests future research directions.