Great news that you are und!
If your white blood cells and anc get too low they either lower you interferon or use neupogen (grow stimulating factor) injections to raise the count. Hopefully they won't go low enough that they have to do either. neupogen is definitely preferred over dose reduction in my opinion but of course this would depend on your doctor's management of the situation.
Take Care - Dave
Denise, your white blood cells are part of your immune system; they keep infections away.
Depending on how low they are, it might be good to keep away from things like ER rooms, day care centers, anything that might expose you to infection or illness.
If it was serious, they probably would have given you specific instructions. Look on your labs (when you receive them) for ANC (absolute neutrophil count); it gets rather serious if they fall below .50 (500).
Keep up the good work in terms of the virus; once you become undetectable for virus, you'll probably stay that way for the rest of treatment.
Bill