The protective properties of early virus-specific proteins (EVSP) of Marburg virus have been studied. Immunoglobulins to EVSP in combination with immunoglobulins to UV-inactivated Marburg virus prevented lethal infection in Marburg virus infected guinea pigs. More than 80% of guinea pigs immunized by mixture of EVSP and UV-inactivated Marburg virus survived after challenge with 25 LD50 of Marburg virus. The explanation of this phenomenon and its further utilization are discussed.
