Not at all! My assigned advisor does ID stuff and that's been my focus in work and school so far, though when I visited a few months ago I met with some ID people and also some chronic people.
As far as stats:
GRE: 660V (I think. It's been awhile.) and 700Q
MPH GPA: 3.9
I have an MPH in epi from a very highly ranked school and have 2 years post-MPH experience in governmental public health.
It seems they're releasing decisions slowly. I know people were notified starting last week and when I visited they said notifications go out as late as March, so I wouldn't worry at all! Since they assign you an advisor upon admission, I bet a lot of the timing is when individual potential advisors have the time to review specific applications.