Abstract: This disclosure provides novel aqueous povidone-iodine (PVP-I) pharmaceutical preparations, which demonstrate strong antimicrobial activity and also strong virucidal activities. The disclosure also provides methods for reducing virus transmission or decreasing risk, incidence or severity of diseases (e.g., COVID-19) or conditions caused by virus infections by topically applying the pharmaceutical preparation of the disclosure to an animal (e.g., a human subject). The disclosure further provides methods of reducing an infection risk posed by microorganisms or viruses in a clinical setting.