The present invention relates to a method for using lectins that bind to pathogens having high mannose surface glycoproteins or fragments thereof which contain high mannose glycoproteins, to remove them from infected blood or plasma in an extracorporeal setting. Accordingly, the present invention provides a method for reducing viral load in an individual comprising the steps of obtaining blood or plasma from the individual, passing the blood or plasma through a porous hollow fiber membrane wherein lectin molecules are immobilized within the porous exterior portion of the membrane, collecting pass-through blood or plasma and reinfusing the pass-through blood or plasma into the individual.