By now, we are all familiar with the plastic barriers to decrease the spread of the coronavirus in stores, schools and even nail salons. Unfortunately, it looks like those didn’t stop the spread of the virus, and it may have made the problem worse. A study published earlier this summer in Science found that desk screens in classrooms were associated with an increased risk of coronavirus infection. Scientists who study air flow and aerosols believe that these plastic dividers, while well-intentioned, change the air flow in a room and can disrupt normal ventilation. They can even create dead zones with little air flow, allowing aerosol particles with the coronavirus to become highly concentrated.