COVID-19 has proven to be an incredible infectious disease. It is able to spread in two major ways: through droplets caused by actions like coughing and then aerosols that occur while we speak and breathe. By limiting the exposure of droplets and air contaminated with the virus we can thus limit infection. Precautions such as wearing a mask, staying at least 6 feet away from other people, and limiting social gatherings to outdoor spaces all help. However, many people that gather outdoors fail to wear a mask or socially distance themselves because they think that being outdoors is enough. This is not true.
Although the risk of contracting COVID through outdoor activities is about 20 times less than indoors, the risk is still there. Modeling droplet and aerosol transmission outdoors is a lot more difficult than modeling indoor interactions due to the amount of variables to take account for. It is still important to take the proper precautions while outside to decrease the risk of transmission.
One of the most important outdoor variables that decreases transmission risk is humidity. Studies have shown that high humidity correlates to lower concentrations of aerosolized pathogens and increases the clearance of pathogens in mucus membranes (nose and throat). This leads to less risk of transmission of disease by aerosols and droplets. On the other side, low humidity increases the risk of transmission and is a main driver of cold/flu season in the late fall and winter months. While gathering outdoors, we want to have the lowest risk of transmission of COVID and other diseases. It is impossible to eliminate risk without choosing not to gather at all. To decrease the risk as much we can, it is so important to continue to socially distance and wear a mask.
Writing by Ryan Mathura, Public Health Innovation Analyst
Ryan is a Master of Public Health Student at Emory University studying Health Policy and Management. He has a background in immunology and worked in vaccine R&D before attending Emory.
Graphics by Sophie Becker, Design Strategist
Sophie is a design strategist at Orange Sparkle Ball. She is a recent graduate from RIT and holds a bachelor’s in industrial design and psychology. Her studies informed her interest in using design thinking to communicate abstract and complex ideas, particularly in public health.
