The letter, as irrelevant as it was, informed that the Inuit population was declining rapidly, as we all knew it would, and stated that once their race was completely wiped out, we had permission to their little remaining resources such as the water, and seeds etc. The letter had the food borne disease, Enzimaë with a small sample of the seed stocks on Earth.
I am on my deathbed having contracted the disease. Unlike we thought, it does not solitarily travel through food. Australia stayed safe all those years because of the wind currents.