Was there a significant epidemic of old world diseases in the new world following the arrival of Viking colonists in North America, similar to the post Columbian epidemics that ravaged the new world ?
Hi there, this is not to discourage further answers, but the "Viking disease" question is fairly frequently asked here. While you wait for more answers, you may be interested in these threads from our FAQ:
http://www.reddit.com/r/AskHistorians/comments/12a3vk/we_all_know_how_there_was_a_huge_population/
Not as far as we know. Even smallpox didn't make it to Iceland until 1241, and the earliest I could find it mentioned being in Greenland is 1430, right as the colony was dying out. It was never endemic even in Iceland, just burned through as short epidemics once every generation or two and then died out. Small populations like those of Greenland and Iceland aren't very good at maintaining disease pools long enough to spread them.