Well, the serum that was relayed by dog-sled was the 300,000 units from Anchorage. That serum held off the diphtheria epidemic until the shipment from Seattle could arrive in late Febuary and finish off the disease in Nome. So they were separate shipments.
That is a very interesting find!

But after what people have told me, I find it a bit hard to trust Wikipedia.

It might be true, though. Hmm....
