I don't know if it would spread as effectively, or with such lethality.
Since it went world wide just 14-15 years earlier, a good bit of the population have already been exposed to it; and those who have been exposed, whether they got sick from it or not, are now immune to the virus and probably any close relative to that virus. (Immune systems have good memories.) So, when they get re-exposed in '34, they don't get sick, AND they don't carry it and spread it to those who aren't immune.