The SARS-CoV-2 virus that causes COVID-19 poses a threat to human health both indoors and outdoors. Besides direct infection from respiratory droplets and aerosols, another mode of transmission involves airborne viruses that linger in the air before settling on and contaminating surfaces. A recently published study by Vetmeduni Vienna has now revealed the extent to which solar UV radiation is effective against SARS-CoV-2 outdoors.