Professor Jarek Kurnitski (IMAGE) Estonian Research Council Caption During the first wave of COVID-19, which paralyzed the world in spring, it was initially thought that effective hand washing and 2-meter social distancing would help prevent the highly contagious virus. Scientists, however, have now come to the conclusion that proper indoor ventilation is even more effective. Credit TalTech Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.