"Current affairs" is a classification of
journalistic material, and is used to categorise
television and
radio shows, as well as columns and
features in
Sunday Supplements.
Whereas news is concerned with circumstances and events that are new, to be applicable to current affairs, they need merely to be current.
For example, a feature on real estate in Arizona would definitely count as current affairs (and of a good deal of interest to the citizens of Arizona). Whereas to be newsworthy, there would have to be an event or change, such as a change in legistlation, or an incident involving Native American Indian rights.
Often current affairs programs can give a great deal more scope to debate of implications of news items, than is available in news coverage (though this is less true now we have 24 hour news channels).