Cross-infection risks of SARS-CoV-2 while playing catch using a baseball: Creating a safe sporting environment during the COVID-19 pandemic.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the coronavirus disease (COVID-19), is found primarily in the respiratory tract secretions of infected individuals with one of the main routes of transmission being direct or indirect contact. In this study, using fluorescent paint, we evaluated the spread of contaminants while playing catch with a baseball. Fluorescent paint was applied to the right hand of a right-handed baseball player who then engaged in playing catch with 10 other right-handed players (partners) for 5 min each. The fluorescent paint was detected on the right hands (inside) and gloves (inside) of all the 10 partners as well as on the ball; in some partners it was also detected on the back of the right hands or the back of the gloves. However, except for their right hands, fluorescent paint was not detected on the surface of the bodies of the partners. These observations indicated that the fluorescent paint (mimicking virus-containing contaminants) on the hand spreads very efficiently from person to person during the throwing and catching of a baseball, suggesting that a thorough and frequent disinfection of the hands and equipment is important in the prevention of infections that may occur while playing baseball.