Hello,
Actually I deactivate influenza virus (swine) with formaldehyde, but by infectivity test on MDCK cells I see cytopathic effects on the first line, so I re-inactivated for the second time with formalin, but I have the same result and this time the cytopathic effect starts from the second row and NOT in the first lig, and its same o by HA test or MDCK cells. Please suggest what is going on?
Thanks