If immune globulin is given one week in advance of exposure will it prevent hepatitis a?

Depends on dose: Immunoglobulin preparations are not checked if they have protective level antibodies anti-hepatitis a. Assuming that most blood donors have enough antibodies anti-hepatitis a, the immunoglobulin preparations should also have enough to neutralize a potential infection. However, this is especulation and it is possible that there could be enough viruses to overcome the neutralzing antibodies received.